ATcT [1, 2] enthalpies of formation based on version 1.118 of the Thermochemical Network [3]

Below is a list of 0 K and 298.15 K enthalpies of formation for all 1058 species included in version 1.118 (as of 10/29/2015).
This version of ATcT results was partially described in Ruscic et al. [4], and was also used for the initial development of high-accuracy ANLn composite electronic structure methods [5].

The elements in their standard states are listed first; the listing order of the other species follows the actual order from the ATcT solution file, which roughly reflects the number of thermochemically-relevant determinations that include the species in question (highest first). The intent is to convey a very approximate indication of the robustness of the listed values, which is generally higher toward the top of the list and lower toward the bottom.

For species other than elements in their standard states, the Species Name acts as a link to the page itemizing the most important contributors to the provenance of its ATcT enthalpy of formation.
(Please note that, as opposed to traditional sequential thermochemistry where the provenance of a given enthalpy of formation is typically a single measurement, the provenances of ATcT enthalpies of formation, which are obtained by analysing and solving a large Thermochemical Network, are normally quite distributed.)

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Species Name	Formula	Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
Dihydrogen	H2 (g)	0	0	exact		2.01588 ± 0.00014	1333-74-0*0
Dioxygen	O2 (g)	0	0	exact		31.99880 ± 0.00060	7782-44-7*0
Graphite	C (graphite)	0	0	exact		12.01070 ± 0.00080	7440-44-0*500
Dinitrogen	N2 (g)	0	0	exact		28.01348 ± 0.00014	7727-37-9*0
Difluorine	F2 (g)	0	0	exact		37.9968064 ± 0.0000010	7782-41-4*0
Dichlorine	Cl2 (g)	0	0	exact		70.9054 ± 0.0018	7782-50-5*0
Dibromine	Br2 (cr,l)	0	0	exact		159.8080 ± 0.0020	7726-95-6*500
Diiodine	I2 (cr,l)	0	0	exact		253.808940 ± 0.000060	7553-56-2*500
Helium	He (g)	0	0	exact		4.0026020 ± 0.0000020	7440-59-7*0
Neon	Ne (g)	0	0	exact		20.17970 ± 0.00060	7440-01-9*0
Argon	Ar (g)	0	0	exact		39.9480 ± 0.0010	7440-37-1*0
Krypton	Kr (g)	0	0	exact		83.8000 ± 0.1000	7439-90-9*0
Xenon	Xe (g)	0	0	exact		131.2900 ± 0.0200	7440-63-3*0
Hydrogen atom	H (g)	216.034	217.998	± 0.000	kJ/mol	1.007940 ± 0.000070	12385-13-6*0
Carbon atom	C (g)	711.395	716.880	± 0.055	kJ/mol	12.01070 ± 0.00080	7440-44-0*0
Oxygen atom	O (g)	246.844	249.229	± 0.0021	kJ/mol	15.99940 ± 0.00030	17778-80-2*0
Nitrogen atom	N (g)	470.573	472.435	± 0.024	kJ/mol	14.006740 ± 0.000070	17778-88-0*0
Fluorine atom	F (g)	77.287	79.393	± 0.055	kJ/mol	18.99840320 ± 0.00000050	14762-94-8*0
Carbon dioxide	CO2 (g)	-393.108	-393.474	± 0.015	kJ/mol	44.0095 ± 0.0010	124-38-9*0
Water	H2O (cr,l)	-286.297	-285.825	± 0.026	kJ/mol	18.01528 ± 0.00033	7732-18-5*500
Methane	CH4 (g)	-66.564	-74.533	± 0.057	kJ/mol	16.04246 ± 0.00085	74-82-8*0
Bromine atom	Br (g)	117.914	111.852	± 0.056	kJ/mol	79.9040 ± 0.0010	10097-32-2*0
Water	H2O (g)	-238.928	-241.831	± 0.026	kJ/mol	18.01528 ± 0.00033	7732-18-5*0
Chlorine atom	Cl (g)	119.621	121.302	± 0.0021	kJ/mol	35.45270 ± 0.00090	22537-15-1*0
Hydron	H+ (g)	1528.084	1530.047	± 0.000	kJ/mol	1.007391 ± 0.000070	12408-02-5*0
Hydrogen chloride	HCl (g)	-91.989	-92.173	± 0.0062	kJ/mol	36.46064 ± 0.00090	7647-01-0*0
Hydroxyl	OH (g)	37.253	37.492	± 0.026	kJ/mol	17.00734 ± 0.00031	3352-57-6*0
Hydrogen bromide	HBr (g)	-27.97	-35.81	± 0.15	kJ/mol	80.9119 ± 0.0010	10035-10-6*0
Carbon monoxide	CO (g)	-113.802	-110.522	± 0.026	kJ/mol	28.01010 ± 0.00085	630-08-0*0
Hydrogen fluoride	HF (g)	-272.644	-272.691	± 0.055	kJ/mol	20.006343 ± 0.000070	7664-39-3*0
Ethylene	C2H4 (g)	61.05	52.53	± 0.14	kJ/mol	28.0532 ± 0.0016	74-85-1*0
Iodine atom	I (g)	107.157	106.757	± 0.0021	kJ/mol	126.904470 ± 0.000030	14362-44-8*0
Ethane	C2H6 (g)	-68.12	-83.75	± 0.15	kJ/mol	30.0690 ± 0.0017	74-84-0*0
Acetylene	HCCH (g)	228.87	228.31	± 0.14	kJ/mol	26.0373 ± 0.0016	74-86-2*0
Methyl radical	CH3 (g)	149.841	146.427	± 0.080	kJ/mol	15.03452 ± 0.00083	2229-07-4*0
Methanol	CH3OH (g)	-189.84	-200.72	± 0.17	kJ/mol	32.04186 ± 0.00090	67-56-1*0
Formaldehyde	H2CO (g)	-105.32	-109.15	± 0.11	kJ/mol	30.02598 ± 0.00087	50-00-0*0
Methyl chloride	CH3Cl (g)	-74.74	-82.68	± 0.20	kJ/mol	50.4872 ± 0.0012	74-87-3*0
Nitric oxide	NO (g)	90.586	91.090	± 0.064	kJ/mol	30.00614 ± 0.00031	10102-43-9*0
Hydrogen iodide	HI (g)	28.643	26.468	± 0.036	kJ/mol	127.912410 ± 0.000076	10034-85-2*0
Hydrogen cyanide	HCN (g)	129.670	129.286	± 0.094	kJ/mol	27.02538 ± 0.00081	74-90-8*0
Ethanol	CH3CH2OH (g)	-216.87	-234.58	± 0.22	kJ/mol	46.0684 ± 0.0017	64-17-5*0
Ammonia	NH3 (g)	-38.568	-45.561	± 0.030	kJ/mol	17.03056 ± 0.00022	7664-41-7*0
Methyl fluoride	CH3F (g)	-228.17	-236.20	± 0.28	kJ/mol	34.03292 ± 0.00083	593-53-3*0
Methyl bromide	CH3Br (g)	-21.00	-36.40	± 0.18	kJ/mol	94.9385 ± 0.0013	74-83-9*0
Nitrogen dioxide	ONO (g)	36.826	34.019	± 0.064	kJ/mol	46.00554 ± 0.00060	10102-44-0*0
Ethyl	CH3CH2 (g)	131.04	119.97	± 0.32	kJ/mol	29.0611 ± 0.0016	2025-56-1*0
Hydroxyde	[OH]- (g)	-139.089	-139.055	± 0.026	kJ/mol	17.00789 ± 0.00031	14280-30-9*0
Tetrafluoromethane	CF4 (g)	-927.47	-933.44	± 0.26	kJ/mol	88.00431 ± 0.00080	75-73-0*0
Fluoride	F- (g)	-250.877	-249.093	± 0.055	kJ/mol	18.99895178 ± 0.00000050	16984-48-8*0
Dioxidanyl	HO2 (g)	15.16	12.25	± 0.16	kJ/mol	33.00674 ± 0.00060	3170-83-0*0
Methylidyne	CH (g)	592.83	596.16	± 0.13	kJ/mol	13.01864 ± 0.00080	3315-37-5*0
Hydrogen peroxide	H2O2 (g)	-129.468	-135.453	± 0.063	kJ/mol	34.01468 ± 0.00062	7722-84-1*0
Dibromine	Br2 (g)	45.68	30.88	± 0.11	kJ/mol	159.8080 ± 0.0020	7726-95-6*0
Acetaldehyde	CH3CHO (g)	-155.00	-165.48	± 0.31	kJ/mol	44.0526 ± 0.0017	75-07-0*0
Propane	CH3CH2CH3 (g)	-82.35	-104.63	± 0.24	kJ/mol	44.0956 ± 0.0025	74-98-6*0
Diiodine	I2 (g)	65.497	62.417	± 0.0041	kJ/mol	253.808940 ± 0.000060	7553-56-2*0
Fluoroform	CF3H (g)	-689.10	-696.05	± 0.44	kJ/mol	70.01385 ± 0.00080	75-46-7*0
Hypoflorous acid	HOF (g)	-84.35	-87.25	± 0.19	kJ/mol	36.00574 ± 0.00031	14034-79-8*0
Hypochlorous acid	HOCl (g)	-73.874	-76.814	± 0.027	kJ/mol	52.46004 ± 0.00095	7790-92-3*0
Hypobromous acid	HOBr (g)	-51.38	-61.85	± 0.57	kJ/mol	96.9113 ± 0.0010	13517-11-8*0
Methyl iodide	CH3I (g)	24.46	14.92	± 0.17	kJ/mol	141.93899 ± 0.00083	74-88-4*0
Tetrachloromethane	CCl4 (g)	-95.33	-97.50	± 0.74	kJ/mol	153.8215 ± 0.0037	56-23-5*0
Benzene	C6H6 (g)	100.71	83.20	± 0.26	kJ/mol	78.1118 ± 0.0048	71-43-2*0
Trifluoromethyl	CF3 (g)	-465.14	-467.93	± 0.53	kJ/mol	69.00591 ± 0.00080	2264-21-3*0
Vinyl	C2H3 (g)	301.20	296.91	± 0.38	kJ/mol	27.0452 ± 0.0016	2669-89-8*0
Allene	CH2CCH2 (g)	197.54	190.06	± 0.32	kJ/mol	40.0639 ± 0.0024	463-49-0*0
Propyne	CH3CCH (g)	192.73	185.67	± 0.32	kJ/mol	40.0639 ± 0.0024	74-99-7*0
Bromide	Br- (g)	-206.623	-212.685	± 0.056	kJ/mol	79.9045 ± 0.0010	24959-67-9*0
Iodide	I- (g)	-187.995	-188.396	± 0.0021	kJ/mol	126.905019 ± 0.000030	20461-54-5*0
Propylene	CH3CHCH2 (g)	35.26	20.26	± 0.29	kJ/mol	42.0797 ± 0.0024	115-07-1*0
Difluorophosgene	COF2 (g)	-603.66	-606.76	± 0.53	kJ/mol	66.00691 ± 0.00085	353-50-4*0
Imidogen	NH (g)	358.75	358.79	± 0.17	kJ/mol	15.014680 ± 0.000099	13774-92-0*0
Oxonium	[H3O]+ (g)	605.55	598.80	± 0.56	kJ/mol	19.02267 ± 0.00037	13968-08-6*0
Methylene	CH2 (g, triplet)	390.96	391.52	± 0.14	kJ/mol	14.02658 ± 0.00081	2465-56-7*1
Methylene	CH2 (g, singlet)	428.63	429.04	± 0.15	kJ/mol	14.02658 ± 0.00081	2465-56-7*2
Cyanogen chloride	ClCN (g)	135.03	135.75	± 0.45	kJ/mol	61.4701 ± 0.0012	506-77-4*0
Tetrabromomethane	CBr4 (g)	132.0	102.3	± 1.1	kJ/mol	331.6267 ± 0.0041	558-13-4*0
Phenyl	C6H5 (g)	350.55	337.27	± 0.59	kJ/mol	77.1039 ± 0.0048	2396-01-2*0
Methylium	[CH3]+ (g)	1099.250	1095.306	± 0.077	kJ/mol	15.03397 ± 0.00083	14531-53-4*0
Methoxide	[CH3O]- (g)	-122.28	-130.27	± 0.37	kJ/mol	31.03447 ± 0.00088	3315-60-4*0
Formic acid	HC(O)OH (g, syn)	-371.20	-378.52	± 0.24	kJ/mol	46.0254 ± 0.0010	64-18-6*1
Hydroxymethyl	CH2OH (g)	-10.44	-16.75	± 0.32	kJ/mol	31.03392 ± 0.00088	2597-43-5*0
Nitric acid	HNO3 (g)	-124.45	-134.16	± 0.18	kJ/mol	63.01288 ± 0.00091	7697-37-2*0
Oxomethylium	[HCO]+ (g)	827.84	827.25	± 0.11	kJ/mol	29.01749 ± 0.00086	17030-74-9*0
Cyano radical	CN (g)	436.72	440.00	± 0.15	kJ/mol	26.01744 ± 0.00080	2074-87-5*0
Methanetetraylbisamidogen	NCN (g)	455.9	456.4	± 1.3	kJ/mol	40.02418 ± 0.00081	2669-76-3*0
Ketene	CH2CO (g)	-45.44	-48.56	± 0.15	kJ/mol	42.0367 ± 0.0016	463-51-4*0
Methylene fluoride	CH2F2 (g)	-443.42	-450.99	± 0.37	kJ/mol	52.02339 ± 0.00081	75-10-5*0
Ozone	OOO (g)	144.395	141.733	± 0.039	kJ/mol	47.99820 ± 0.00090	10028-15-6*0
Chloride	Cl- (g)	-228.953	-227.346	± 0.0031	kJ/mol	35.45325 ± 0.00090	16887-00-6*0
Cyanogen fluoride	FCN (g)	8.41	8.74	± 0.73	kJ/mol	45.01584 ± 0.00080	1495-50-7*0
Methoxy radical	CH3O (g)	29.19	21.81	± 0.37	kJ/mol	31.03392 ± 0.00088	2143-68-2*0
Formyl	HCO (g)	41.46	41.84	± 0.11	kJ/mol	29.01804 ± 0.00086	2597-44-6*0
2-Propynyl	CH2CCH (g)	354.09	351.53	± 0.39	kJ/mol	39.0559 ± 0.0024	2932-78-7*0
Propynylidene	HCCCH (g, triplet)	543.08	546.08	± 0.67	kJ/mol	38.0480 ± 0.0024	67152-18-5*1
Hypochlorite	[ClO]- (g)	-118.61	-118.34	± 0.13	kJ/mol	51.45265 ± 0.00095	14380-61-1*0
Oxygen atom anion	O- (g)	105.868	108.097	± 0.0021	kJ/mol	15.99995 ± 0.00030	14337-01-0*0
Cyanogen bromide	BrCN (g)	187.57	180.78	± 0.78	kJ/mol	105.9214 ± 0.0013	506-68-3*0
Allyl	CH2CHCH2 (g)	179.71	167.98	± 0.55	kJ/mol	41.0718 ± 0.0024	1981-80-2*0
1-Hydroxyethyl	CH3CHOH (g, gauche-anti)	-42.07	-55.50	± 0.62	kJ/mol	45.0605 ± 0.0017	2348-46-1*1
2-Hydroxyethyl	CH2CH2OH (g, gauche-syn)	-12.75	-26.01	± 0.61	kJ/mol	45.0605 ± 0.0017	4422-54-2*1
Cyanato	NCO (g)	126.91	127.38	± 0.38	kJ/mol	42.01684 ± 0.00086	22400-26-6*0
Ethyl chloride	CH3CH2Cl (g)	-96.67	-111.26	± 0.22	kJ/mol	64.5138 ± 0.0019	75-00-3*0
Oxygen difluoride	FOF (g)	26.96	24.71	± 0.25	kJ/mol	53.99621 ± 0.00030	7783-41-7*0
Hydride	H- (g)	143.264	145.228	± 0.000	kJ/mol	1.008489 ± 0.000070	12184-88-2*0
Nitrite	[ONO]- (g)	-182.66	-185.46	± 0.46	kJ/mol	46.00609 ± 0.00060	14797-65-0*0
Nitrosyl hydride	HNO (g)	109.90	106.93	± 0.11	kJ/mol	31.01408 ± 0.00032	14332-28-6*0
Ethynyl	C2H (g)	563.91	568.02	± 0.15	kJ/mol	25.0293 ± 0.0016	2122-48-7*0
Ethoxide	[CH3CH2O]- (g)	-163.56	-178.50	± 0.53	kJ/mol	45.0610 ± 0.0017	16331-64-9*0
Tetrafluoroethylene	C2F4 (g)	-671.58	-675.00	± 0.61	kJ/mol	100.0150 ± 0.0016	116-14-3*0
Phenylium	[C6H5]+ (g)	1148.74	1136.84	± 0.95	kJ/mol	77.1034 ± 0.0048	17333-73-2*0
Chloroxyl radical	ClO (g)	101.116	101.707	± 0.035	kJ/mol	51.45210 ± 0.00095	14989-30-1*0
Hypoiodous acid	HOI (g)	-56.6	-61.3	± 2.0	kJ/mol	143.91181 ± 0.00031	14332-21-9*0
Trihydrogen cation	[H3]+ (g)	1110.304	1106.696	± 0.013	kJ/mol	3.02327 ± 0.00021	28132-48-1*0
Nitrous oxide	NNO (g)	86.003	82.574	± 0.097	kJ/mol	44.01288 ± 0.00033	10024-97-2*0
Amidogen	NH2 (g)	188.94	186.05	± 0.15	kJ/mol	16.02262 ± 0.00016	13770-40-6*0
Hydroxylamine	NH2OH (g, trans)	-33.13	-43.50	± 0.49	kJ/mol	33.02996 ± 0.00037	7803-49-8*1
1,2-Propadiene-1,3-diylidene	CCC (g)	815.52	824.47	± 0.84	kJ/mol	36.0321 ± 0.0024	12075-35-3*0
Oxirane	O(CH2CH2) (g)	-40.19	-52.73	± 0.44	kJ/mol	44.0526 ± 0.0017	75-21-8*0
Tetraiodomethane	CI4 (g)	340.5	335.4	± 1.4	kJ/mol	519.62858 ± 0.00081	507-25-5*0
Chlorotrifluoromethane	CF3Cl (g)	-705.09	-710.20	± 0.72	kJ/mol	104.4586 ± 0.0012	75-72-9*0
Bromotrifluoromethane	CF3Br (g)	-639.51	-651.63	± 0.53	kJ/mol	148.9099 ± 0.0013	75-63-8*0
Fluoromethylidyne	CF (g)	243.15	246.75	± 0.14	kJ/mol	31.00910 ± 0.00080	3889-75-6*0
Methylenimine	H2CNH (g)	96.61	88.70	± 0.98	kJ/mol	29.04126 ± 0.00083	2053-29-4*0
Fluoroxyl radical	FO (g)	110.31	110.93	± 0.15	kJ/mol	34.99780 ± 0.00030	12061-70-0*0
Methylamine	CH3NH2 (g)	-5.82	-20.91	± 0.53	kJ/mol	31.05714 ± 0.00088	74-89-5*0
Ethylium	[CH3CH2]+ (g)	915.06	902.82	± 0.36	kJ/mol	29.0606 ± 0.0016	14936-94-8*0
Ethoxy	CH3CH2O (g, X 2A")	1.67	-12.24	± 0.52	kJ/mol	45.0605 ± 0.0017	2154-50-9*51
Isocyanic acid	HNCO (g)	-116.04	-119.03	± 0.37	kJ/mol	43.02478 ± 0.00086	75-13-8*0
Chloroform	CCl3H (g)	-98.58	-103.48	± 0.65	kJ/mol	119.3767 ± 0.0028	67-66-3*0
Methylene chloride	CH2Cl2 (g)	-87.82	-94.68	± 0.60	kJ/mol	84.9320 ± 0.0020	75-09-2*0
Vinyl chloride	CH2CHCl (g)	29.56	22.09	± 0.35	kJ/mol	62.4979 ± 0.0018	75-01-4*0
Acetone	CH3C(O)CH3 (g)	-199.41	-216.10	± 0.37	kJ/mol	58.0791 ± 0.0025	67-64-1*0
Hydrogen fluoride	HF (aq)		-334.53	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*800
Hypobromite	[BrO]- (g)	-96.22	-103.70	± 0.55	kJ/mol	95.9039 ± 0.0010	14380-62-2*0
Diazenylium	[N2H]+ (g)	1042.77	1039.16	± 0.73	kJ/mol	29.02087 ± 0.00016	12357-66-3*0
n-Butane	CH3CH2CH2CH3 (g)	-98.51	-125.82	± 0.34	kJ/mol	58.1222 ± 0.0033	106-97-8*0
Propadienylidene	CH2CC (g)	554.50	555.64	± 0.43	kJ/mol	38.0480 ± 0.0024	60731-10-4*0
Acetyl	CH3CO (g)	-3.20	-9.86	± 0.38	kJ/mol	43.0446 ± 0.0016	3170-69-2*0
Methyl hydroperoxide	CH3OOH (g)	-114.97	-127.79	± 0.91	kJ/mol	48.0413 ± 0.0010	3031-73-0*0
Hydroxyformyl	HOCO (g, trans)	-180.95	-183.91	± 0.48	kJ/mol	45.0174 ± 0.0010	2564-86-5*1
Ethyl bromide	CH3CH2Br (g)	-41.19	-63.14	± 0.27	kJ/mol	108.9651 ± 0.0019	74-96-4*0
Vinyl fluoride	CH2CHF (g)	-134.4	-142.3	± 1.1	kJ/mol	46.0436 ± 0.0016	75-02-5*0
Vinyl bromide	CH2CHBr (g)	88.51	73.71	± 0.61	kJ/mol	106.9492 ± 0.0019	593-60-2*0
2-Bromoethanol	BrCH2CH2OH (g)	-196.67	-220.74	± 0.54	kJ/mol	124.9645 ± 0.0019	540-51-2*0
Fluorobenzene	C6H5F (g)	-99.6	-115.3	± 1.1	kJ/mol	96.1023 ± 0.0048	462-06-6*0
(E)-Diazene	HNNH (g, trans)	207.36	200.22	± 0.56	kJ/mol	30.02936 ± 0.00020	15626-43-4*0
Hydroxyoxomethylium	[HOCO]+ (g)	600.80	597.72	± 0.45	kJ/mol	45.0169 ± 0.0010	638-71-1*0
Ethynylene	C2 (g)	820.26	828.33	± 0.30	kJ/mol	24.0214 ± 0.0016	12070-15-4*0
Vinylium	[C2H3]+ (g)	1118.89	1115.87	± 0.60	kJ/mol	27.0447 ± 0.0016	14604-48-9*0
Hydroxymethylium	[CH2OH]+ (g)	717.93	709.99	± 0.21	kJ/mol	31.03337 ± 0.00088	18682-95-6*0
Cyanogen	NCCN (g)	308.17	310.12	± 0.43	kJ/mol	52.0349 ± 0.0016	460-19-5*0
Cyanogen iodide	ICN (g)	222.6	222.1	± 1.0	kJ/mol	152.92191 ± 0.00080	506-78-5*0
Ethynide	[C2H]- (g)	277.57	281.06	± 0.40	kJ/mol	25.0299 ± 0.0016	29075-95-4*0
Dioxidanide	[HO2]- (g)	-88.88	-91.55	± 0.39	kJ/mol	33.00729 ± 0.00060	14691-59-9*0
Phosgene	COCl2 (g)	-217.32	-219.02	± 0.28	kJ/mol	98.9155 ± 0.0020	75-44-5*0
2-Chloroethanol	ClCH2CH2OH (g)	-250.06	-266.78	± 0.61	kJ/mol	80.5132 ± 0.0019	107-07-3*0
Hypofluorite	[FO]- (g)	-108.94	-108.76	± 0.48	kJ/mol	34.99835 ± 0.00030	12763-66-5*0
Hydrogen chloride	HCl (aq, 600 H2O)		-166.454	± 0.024	kJ/mol	36.46064 ± 0.00090	7647-01-0*834
Methanium	[CH5]+ (g)	921.75	911.09	± 0.46	kJ/mol	17.04985 ± 0.00087	15135-49-6*0
Hydroxyamidogen	HNOH (g, trans)	101.5	94.7	± 1.0	kJ/mol	32.02202 ± 0.00034	13940-32-4*1
Nitrate	[NO3]- (g)	-300.14	-306.60	± 0.61	kJ/mol	62.00549 ± 0.00090	14797-55-8*0
Dioxygenyl fluoride	FOO (g)	26.79	25.08	± 0.26	kJ/mol	50.99720 ± 0.00060	15499-23-7*0
Propyl	CH3CH2CH2 (g)	118.28	101.17	± 0.63	kJ/mol	43.0877 ± 0.0024	2143-61-5*0
iso-Propyl	CH3CHCH3 (g)	105.75	89.15	± 0.70	kJ/mol	43.0877 ± 0.0024	2025-55-0*0
2-Propynylidyne	CCCH (g)	718.12	722.47	± 0.83	kJ/mol	37.0400 ± 0.0024	53590-28-6*0
Bromoform	CBr3H (g)	73.7	47.5	± 1.3	kJ/mol	252.7306 ± 0.0031	75-25-2*0
2-Fluoroethanol	FCH2CH2OH (g)	-406.9	-424.1	± 1.1	kJ/mol	64.0589 ± 0.0017	371-62-0*0
Phenide	[C6H5]- (g)	244.88	231.97	± 0.44	kJ/mol	77.1044 ± 0.0048	30922-78-2*0
Bromobenzene	C6H5Br (g)	127.0	104.9	± 1.3	kJ/mol	157.0079 ± 0.0049	108-86-1*0
Bromoxyl radical	BrO (g)	131.16	123.62	± 0.30	kJ/mol	95.9034 ± 0.0010	15656-19-6*0
Iodine monochloride	ICl (g)	19.024	17.391	± 0.013	kJ/mol	162.35717 ± 0.00090	7790-99-0*0
Iodotrifluoromethane	CF3I (g)	-584.05	-589.93	± 0.56	kJ/mol	195.91038 ± 0.00080	2314-97-8*0
Nitroxyl	H2NO (g)	71.33	64.73	± 0.85	kJ/mol	32.02202 ± 0.00034	13408-29-2*0
Peroxynitrous acid	HOONO (g, cis, cis)	-6.14	-14.58	± 0.37	kJ/mol	63.01288 ± 0.00091	14691-52-2*3
Acetylium	[CH3CO]+ (g)	666.91	659.74	± 0.68	kJ/mol	43.0441 ± 0.0016	15762-07-9*0
Hydroxymethylene	HCOH (g, trans)	111.98	108.21	± 0.41	kJ/mol	30.02598 ± 0.00087	19710-56-6*1
Formyl anion	[HCO]- (g)	11.62	12.05	± 0.44	kJ/mol	29.01859 ± 0.00086	57340-31-5*0
1-Hydroxyethylium	[CH3CHOH]+ (g, anti)	609.20	594.78	± 0.40	kJ/mol	45.0600 ± 0.0017	18682-96-7*1
Ethoxy	CH3CH2O (g, A 2A')	5.92	-8.52	± 0.52	kJ/mol	45.0605 ± 0.0017	2154-50-9*52
Methylperoxy	CH3OO (g)	21.85	12.10	± 0.89	kJ/mol	47.0333 ± 0.0010	2143-58-0*0
Formic acid	HC(O)OH (g, anti)	-354.86	-362.11	± 0.40	kJ/mol	46.0254 ± 0.0010	64-18-6*2
Formyloxy	HC(O)O (g, 2A1 only)	-124.68	-126.34	± 0.53	kJ/mol	45.0174 ± 0.0010	16499-21-1*1
Formate	[HC(O)O]- (g)	-462.02	-465.67	± 0.53	kJ/mol	45.0180 ± 0.0010	71-47-6*0
Chlorodifluoromethane	CHClF2 (g)	-476.7	-482.8	± 1.2	kJ/mol	86.4681 ± 0.0012	75-45-6*0
Fluoromethylene	CHF (g, singlet)	148.34	148.62	± 0.46	kJ/mol	32.01704 ± 0.00080	13453-52-6*2
Ethyl fluoride	CH3CH2F (g)	-257.45	-272.31	± 0.95	kJ/mol	48.0595 ± 0.0016	353-36-6*0
Chlorobenzene	C6H5Cl (g)	67.18	52.23	± 0.61	kJ/mol	112.5566 ± 0.0049	108-90-7*0
Hydrogen bromide	HBr (aq)		-120.95	± 0.15	kJ/mol	80.9119 ± 0.0010	10035-10-6*800
Hydrogen chloride	HCl (aq)		-166.993	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*800
Oxygen atom cation	O+ (g)	1560.786	1562.644	± 0.0021	kJ/mol	15.99885 ± 0.00030	14581-93-2*0
Amide	[NH2]- (g)	114.95	112.08	± 0.34	kJ/mol	16.02317 ± 0.00016	17655-31-1*0
Hydrazine	H2NNH2 (g)	109.71	95.55	± 0.19	kJ/mol	32.04524 ± 0.00031	302-01-2*0
Methylidyne	CH (g, quartet)	664.45	667.79	± 0.63	kJ/mol	13.01864 ± 0.00080	3315-37-5*2
Ethylidyne	CH3C (g)	510.3	506.3	± 1.1	kJ/mol	27.0452 ± 0.0016	67624-57-1*0
Trioxidane	HOOOH (g, trans)	-81.40	-90.24	± 0.78	kJ/mol	50.01408 ± 0.00091	14699-99-1*1
1-Methylethenyl	CH3CCH2 (g)	263.15	252.81	± 0.72	kJ/mol	41.0718 ± 0.0024	15552-77-9*0
1-Hydroxyethyl	CH3CHOH (g, gauche-syn)	-40.51	-53.98	± 0.87	kJ/mol	45.0605 ± 0.0017	2348-46-1*2
Protonated oxirane	[(CH2CH2)OH]+ (g)	725.18	709.01	± 0.64	kJ/mol	45.0600 ± 0.0017	38607-31-70
Oxoethenyl	HCCO (g)	176.88	177.99	± 0.60	kJ/mol	41.0287 ± 0.0016	51095-15-9*0
Methanediol	CH2(OH)2 (g, conrot gauche)	-379.15	-393.35	± 0.96	kJ/mol	48.0413 ± 0.0010	463-57-0*1
Acetyl chloride	CH3C(O)Cl (g)	-232.68	-241.55	± 0.33	kJ/mol	78.4973 ± 0.0019	75-36-5*0
Fluoronium	[HFH]+ (g)	774.25	771.31	± 0.90	kJ/mol	21.01373 ± 0.00014	12206-67-6*0
Trioxidanide	[HOOO]- (g, gauche)	-121.0	-124.0	± 1.4	kJ/mol	49.00669 ± 0.00090	89965-38-8*2
Methylene bromide	CH2Br2 (g)	24.6	3.2	± 1.2	kJ/mol	173.8346 ± 0.0022	74-95-3*0
Difluorodichloromethane	CF2Cl2 (g)	-491.00	-495.77	± 0.98	kJ/mol	120.9129 ± 0.0020	75-71-8*0
Fluorodichloromethane	CHFCl2 (g)	-279.1	-284.4	± 1.2	kJ/mol	102.9224 ± 0.0020	75-43-4*0
Iodoxyl radical	IO (g)	127.0	125.0	± 1.1	kJ/mol	142.90387 ± 0.00030	14696-98-1*0
Nitrogen sesquioxide	ONNO2 (g)	90.66	86.09	± 0.15	kJ/mol	76.01168 ± 0.00091	10544-73-7*0
Ammonium	[NH4]+ (g)	643.02	631.71	± 0.21	kJ/mol	18.03795 ± 0.00029	14798-03-9*0
Ammonium	[NH4]+ (aq)		-133.083	± 0.056	kJ/mol	18.03795 ± 0.00029	14798-03-9*800
Hydrazyl	N2H3 (g)	235.52	224.87	± 0.93	kJ/mol	31.03730 ± 0.00025	13598-46-4*0
Hydrazoic acid	HNNN (g)	298.13	291.83	± 0.58	kJ/mol	43.02816 ± 0.00022	7782-79-8*0
Dioxygen cation	[O2]+ (g)	1164.585	1165.221	± 0.0092	kJ/mol	31.99825 ± 0.00060	12185-07-8*0
Hydrogen peroxide cation	[H2O2]+ (g, trans)	896.85	889.87	± 0.57	kJ/mol	34.01413 ± 0.00062	12325-10-9*1
Ethylidene	CH3CH (g, triplet)	361.5	354.5	± 1.2	kJ/mol	28.0532 ± 0.0016	4218-50-2*1
Chloronium	[HClH]+ (g)	881.2	878.1	± 1.2	kJ/mol	37.46803 ± 0.00091	36658-55-6*0
Hydrogen isocyanide cation	[HNC]+ (g)	1352.9	1352.9	± 1.4	kJ/mol	27.02483 ± 0.00081	74158-11-5*0
Dioxygen difluoride	FOOF (g)	37.36	33.64	± 0.38	kJ/mol	69.99561 ± 0.00060	7783-44-0*0
2-Hydroxyethyl	CH2CH2OH (g, gauche-anti)	-9.91	-22.54	± 0.86	kJ/mol	45.0605 ± 0.0017	4422-54-2*2
Methanediol	CH2(OH)2 (g, disrot gauche)	-368.6	-381.8	± 1.0	kJ/mol	48.0413 ± 0.0010	463-57-0*2
Hydroperoxonium	[H2OOH]+ (g, trans)	738.1	727.8	± 1.0	kJ/mol	35.02207 ± 0.00064	70850-26-9*1
Trifluoromethylium	[CF3]+ (g)	408.93	405.86	± 0.54	kJ/mol	69.00536 ± 0.00080	18851-76-8*0
Fluoroformyl	FCO (g)	-176.92	-176.34	± 0.51	kJ/mol	47.00850 ± 0.00085	1871-24-5*0
Bromonium	[HBrH]+ (g)	924.8	914.1	± 1.6	kJ/mol	81.9193 ± 0.0010	36658-54-5*0
Oxonitrate anion	[NO]- (g)	87.88	87.91	± 0.12	kJ/mol	30.00669 ± 0.00031	14967-78-3*0
Chlorine fluoride	ClF (g)	-55.589	-55.684	± 0.060	kJ/mol	54.45110 ± 0.00090	7790-89-8*0
Nitric acid	HNO3 (aq)		-206.60	± 0.19	kJ/mol	63.01288 ± 0.00091	7697-37-2*800
Oxoammoniumyl	[HNO]+ (g)	1092.49	1089.56	± 0.70	kJ/mol	31.01353 ± 0.00032	63559-87-5*0
Nitrous acid	HONO (g, trans)	-73.048	-79.191	± 0.078	kJ/mol	47.01348 ± 0.00061	7782-77-6*1
Peroxynitrous acid	HOONO (g, trans, perp)	7.56	0.48	± 0.42	kJ/mol	63.01288 ± 0.00091	14691-52-2*1
Ethylidene	CH3CH (g, singlet)	374.6	366.9	± 1.2	kJ/mol	28.0532 ± 0.0016	4218-50-2*2
Iminomethyl cation	[HCNH]+ (g)	953.4	949.3	± 1.6	kJ/mol	28.03277 ± 0.00082	196216-36-1*0
Cyclopropane	CH2(CH2CH2) (g)	70.77	53.62	± 0.49	kJ/mol	42.0797 ± 0.0024	75-19-4*0
1-Propenyl	CH3CHCH (g, cis)	278.13	267.34	± 0.80	kJ/mol	41.0718 ± 0.0024	6067-68-1*2
1-Propynyl	CH3CC (g)	528.99	526.63	± 0.81	kJ/mol	39.0559 ± 0.0024	89342-91-6*0
Trioxidane	HOOOH (g, cis)	-72.01	-80.50	± 0.83	kJ/mol	50.01408 ± 0.00091	14699-99-1*2
Propargylenide	[HCCCH]- (g, transoid 2B)	436.54	439.06	± 0.98	kJ/mol	38.0485 ± 0.0024	82906-05-6*1
2-Propyn-1-ylium-1-ylidene	[CCCH]+ (g)	1598.4	1603.3	± 1.3	kJ/mol	37.0395 ± 0.0024	75104-46-0*0
2-Hydroxyethyl	CH2CH2OH (g, staggered-anti)	-4.9	-17.3	± 1.2	kJ/mol	45.0605 ± 0.0017	4422-54-2*3
Vinoxy	CH2CHO (g)	22.48	15.64	± 0.77	kJ/mol	43.0446 ± 0.0016	6912-06-7*0
Acetyl anion	[CH3CO]- (g)	-43.8	-49.3	± 1.3	kJ/mol	43.0452 ± 0.0016	78944-68-0*0
Ketene	CH2CO (g, triplet)	182.6	179.6	± 1.3	kJ/mol	42.0367 ± 0.0016	463-51-4*1
Dicarbon monoxide	CCO (g, triplet)	375.0	379.0	± 1.2	kJ/mol	40.0208 ± 0.0016	12071-23-7*1
Dimethyl ether	CH3OCH3 (g)	-166.52	-184.02	± 0.44	kJ/mol	46.0684 ± 0.0017	115-10-6*0
Formic acid	HC(O)OH (g, syn-anti equilib)	-371.20	-378.50	± 0.24	kJ/mol	46.0254 ± 0.0010	64-18-6*0
Hydroxyformyl	HOCO (g, cis)	-174.03	-177.05	± 0.51	kJ/mol	45.0174 ± 0.0010	2564-86-5*2
Hydroxyformyl anion	[HOCO]- (g, cis)	-319.35	-322.12	± 0.58	kJ/mol	45.0180 ± 0.0010	78944-70-4*2
Fluorotrichloromethane	CCl3F (g)	-287.4	-290.6	± 1.2	kJ/mol	137.3672 ± 0.0028	75-69-4*0
Bromotrichloromethane	CCl3Br (g)	-33.88	-43.03	± 0.73	kJ/mol	198.2728 ± 0.0030	75-62-7*0
Difluoromethylene	CF2 (g)	-193.87	-193.39	± 0.42	kJ/mol	50.00751 ± 0.00080	2154-59-8*0
2-Hydrotrioxy	OO(H)O (g)	300.9	295.2	± 1.1	kJ/mol	49.00614 ± 0.00090	12500-78-60
Fluoromethylene	CHF (g, triplet)	210.18	210.52	± 0.68	kJ/mol	32.01704 ± 0.00080	13453-52-6*1
Hydrogen fluoride	HF (aq, 20 H2O)		-321.07	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*818
1,1-Difluoroethene	CH2CF2 (g)	-343.69	-350.75	± 0.86	kJ/mol	64.0341 ± 0.0016	75-38-7*0
Tricarbon dioxide	OCCCO (g)	-96.2	-94.1	± 1.2	kJ/mol	68.0309 ± 0.0025	504-64-3*0
Dichloride	[Cl2]- (g)	-230.7	-229.7	± 1.8	kJ/mol	70.9059 ± 0.0018	12595-89-0*0
Iodobenzene	C6H5I (g)	177.8	161.9	± 1.1	kJ/mol	204.0084 ± 0.0048	591-50-4*0
Iodine monobromide	IBr (g)	49.715	40.768	± 0.067	kJ/mol	206.8085 ± 0.0010	7789-33-5*0
Trioxidanyl	HOOO (g, trans)	25.32	23.33	± 0.13	kJ/mol	49.00614 ± 0.00090	12500-78-6*1
Isodiazene	H2NN (g)	308.00	300.94	± 0.81	kJ/mol	30.02936 ± 0.00020	28647-38-3*0
Methide	[CH3]- (g)	145.50	142.06	± 0.95	kJ/mol	15.03507 ± 0.00083	15194-58-8*0
Methyliumyl	[CH2]+ (g)	1393.10	1393.96	± 0.14	kJ/mol	14.02603 ± 0.00081	15091-72-2*0
Difluoride	[F2]- (g)	-291.0	-290.2	± 1.5	kJ/mol	37.9973550 ± 0.0000010	12184-85-9*0
Oxoniumylidene	[OH]+ (g)	1293.193	1293.222	± 0.035	kJ/mol	17.00679 ± 0.00031	12259-29-9*0
Ozonide ion	[OOO]- (g)	-58.48	-60.83	± 0.21	kJ/mol	47.99875 ± 0.00090	12596-80-4*0
(E)-Iminomethyl	HCNH (g, trans)	276.2	272.6	± 1.4	kJ/mol	28.03332 ± 0.00082	54980-10-8*0
Fluoroacetylene	HCCF (g)	104.35	105.06	± 0.85	kJ/mol	44.0277 ± 0.0016	2713-09-9*0
Chloroacetylene	HCCCl (g)	228.1	229.0	± 1.1	kJ/mol	60.4820 ± 0.0018	593-63-5*0
1,2-Propadienyl anion	[CH2CCH]- (g)	265.88	262.68	± 0.72	kJ/mol	39.0565 ± 0.0024	64066-06-4*0
1-Propynyl anion	[CH3CC]- (g)	265.04	261.57	± 0.81	kJ/mol	39.0565 ± 0.0024	36147-87-2*0
Propargylenide	[HCCCH]- (g, cisoid 2A)	439.08	441.59	± 0.86	kJ/mol	38.0485 ± 0.0024	82906-05-6*2
2-Hydroxyethylium	[CH2CH2OH]+ (g, staggered-anti)	1019.6	1006.8	± 1.6	kJ/mol	45.0600 ± 0.0017	38607-31-7*3
Vinyl alcohol	CH2CHOH (g, syn)	-112.59	-123.90	± 0.87	kJ/mol	44.0526 ± 0.0017	557-75-5*1
Bromine monochloride	BrCl (g)	21.878	14.434	± 0.060	kJ/mol	115.3567 ± 0.0013	13863-41-7*0
Dicarbon monoxide	CCO (g, singlet)	453.6	457.9	± 1.3	kJ/mol	40.0208 ± 0.0016	12071-23-7*2
Hydroxyformyl anion	[HOCO]- (g, trans)	-313.52	-315.46	± 0.59	kJ/mol	45.0180 ± 0.0010	78944-70-4*1
Acetic acid	CH3C(O)OH (g, syn)	-418.72	-432.84	± 0.62	kJ/mol	60.0520 ± 0.0017	64-19-7*1
Ethylene glycol	(CH2OH)2 (g)	-369.79	-389.42	± 0.49	kJ/mol	62.0678 ± 0.0018	107-21-1*0
Cyanoamidogen	HNCN (g)	324.6	322.1	± 1.6	kJ/mol	41.03212 ± 0.00082	12347-01-2*0
Fluorochloromethane	CH2FCl (g)	-256.6	-263.7	± 1.3	kJ/mol	68.4777 ± 0.0012	593-70-4*0
Formyl fluoride	HFCO (g)	-378.98	-382.56	± 0.48	kJ/mol	48.01644 ± 0.00086	1493-02-3*0
1,3-Butadiyne	HCCCCH (g)	458.63	460.35	± 0.87	kJ/mol	50.0587 ± 0.0032	460-12-8*0
Fluorobenzene cation	[C6H5F]+ (g)	788.3	773.6	± 1.1	kJ/mol	96.1018 ± 0.0048	34468-25-2*0
Nitrosyl nitrite	ONONO (g, sym)	91.2	86.1	± 1.6	kJ/mol	76.01168 ± 0.00091	122413-35-8*1
Dinitrogen pentoxide	O2NONO2 (g)	24.33	14.76	± 0.35	kJ/mol	108.0105 ± 0.0015	10102-03-1*0
Bromide	Br- (aq)		-120.95	± 0.15	kJ/mol	79.9045 ± 0.0010	24959-67-9*800
Carbon atom cation	C+ (g)	1797.848	1803.446	± 0.055	kJ/mol	12.01015 ± 0.00080	14067-05-1*0
Oxoniumyl ion	[H2O]+ (g)	978.475	975.572	± 0.029	kJ/mol	18.01473 ± 0.00033	56583-62-1*0
Fluoride	F- (aq)		-334.53	± 0.17	kJ/mol	18.99895178 ± 0.00000050	16984-48-8*800
Vinyl anion	[C2H3]- (g)	237.39	232.99	± 0.84	kJ/mol	27.0458 ± 0.0016	25012-81-1*0
Acetylene cation	[HCCH]+ (g)	1328.62	1327.69	± 0.20	kJ/mol	26.0367 ± 0.0016	25641-79-6*0
Vinylidene	CCH2 (g)	411.33	412.24	± 0.62	kJ/mol	26.0373 ± 0.0016	2143-69-3*0
Vinylidene anion	[CCH2]- (g)	364.30	364.11	± 0.81	kJ/mol	26.0378 ± 0.0016	66295-36-1*0
Ethynylium	[C2H]+ (g)	1687.63	1690.96	± 0.17	kJ/mol	25.0288 ± 0.0016	16456-59-0*0
Methylamidogen anion	[CH3NH]- (g)	146.14	134.79	± 0.79	kJ/mol	30.04975 ± 0.00085	54448-39-4*0
Methyleneamidogen	H2CN (g)	242.23	238.57	± 0.95	kJ/mol	28.03332 ± 0.00082	15845-29-1*0
(Z)-Iminomethyl	HCNH (g, cis)	294.6	291.1	± 1.4	kJ/mol	28.03332 ± 0.00082	54980-11-9*0
Water anion	[(H)(OH)]- (g, vdW)	30.5	29.0	± 2.5	kJ/mol	18.01583 ± 0.00033	12259-30-2*100
Methyloxoniumylidene	[CH3O]+ (g)	1062.57	1054.94	± 0.71	kJ/mol	31.03337 ± 0.00088	58157-09-8*0
Hydroxymethylene	HCOH (g, cis)	130.42	126.68	± 0.42	kJ/mol	30.02598 ± 0.00087	19710-56-6*2
Hydroxymethylene cation	[HCOH]+ (g, trans)	972.2	968.6	± 1.6	kJ/mol	30.02543 ± 0.00087	135395-06-1*1
Dioxidenium	[HO2]+ (g)	1110.87	1107.98	± 0.11	kJ/mol	33.00619 ± 0.00060	12207-52-2*0
1-Propenyl	CH3CHCH (g, trans)	280.18	269.36	± 0.81	kJ/mol	41.0718 ± 0.0024	6067-68-1*1
Cyclopropene	CH2(CHCH) (g)	292.59	283.86	± 0.55	kJ/mol	40.0639 ± 0.0024	2781-85-3*0
1-Hydroxyethylium	[CH3CHOH]+ (g, syn)	611.2	596.7	± 1.2	kJ/mol	45.0600 ± 0.0017	18682-96-7*2
Vinyl alcohol	CH2CHOH (g, anti)	-108.14	-118.67	± 0.90	kJ/mol	44.0526 ± 0.0017	557-75-5*2
Vinyl alcohol cation	[CH2CHOH]+ (g, anti)	779.1	767.9	± 1.2	kJ/mol	44.0520 ± 0.0017	57239-63-1*2
Oxiranyl	CH2(CHO) (g)	172.8	164.5	± 1.4	kJ/mol	43.0446 ± 0.0016	31586-84-2*0
Oxiranylium	[CH2(CHO)]+ (g, singlet)	901.5	893.5	± 1.4	kJ/mol	43.0441 ± 0.0016	57789-76-1*2
C=O=C	COC (g, triplet)	652.7	657.0	± 2.3	kJ/mol	40.0208 ± 0.0016	12071-23-71
C=O=C	COC (g, singlet)	720.9	725.2	± 1.7	kJ/mol	40.0208 ± 0.0016	12071-23-72
Oxirene	O(CHCH) (g, t-triplet)	390.0	385.7	± 2.8	kJ/mol	42.0367 ± 0.0016	157-18-6*11
Ethynol	HCCOH (g)	94.8	92.7	± 1.4	kJ/mol	42.0367 ± 0.0016	32038-79-2*0
Formic acid cation	[HC(O)OH]+ (g, syn)	721.78	714.62	± 0.28	kJ/mol	46.0248 ± 0.0010	50614-05-6*1
Dioxirane	H2C(OO) (g)	9.26	1.58	± 0.92	kJ/mol	46.0254 ± 0.0010	157-26-6*0
Formyloxy	HC(O)O (g, 2B2 only)	-120.86	-124.20	± 0.54	kJ/mol	45.0174 ± 0.0010	16499-21-1*2
Isofulminic acid	HCNO (g)	170.8	169.3	± 1.2	kJ/mol	43.02478 ± 0.00086	51060-05-0*0
Methyl formate	HC(O)OCH3 (g, syn-staggered)	-344.74	-357.79	± 0.58	kJ/mol	60.0520 ± 0.0017	107-31-3*1
Diazomethyl	HCNN (g)	472.5	470.0	± 1.8	kJ/mol	41.03212 ± 0.00082	20813-32-5*0
Isocyanoamidogen	HNNC (g)	492.4	490.4	± 1.8	kJ/mol	41.03212 ± 0.00082	947408-73-3*0
Trioxidanylium	[HOOO]+ (g, trans)	1070.2	1063.9	± 1.3	kJ/mol	49.00559 ± 0.00090	74241-49-9*1
Methyl iodide	CH3I (l)		-12.22	± 0.19	kJ/mol	141.93899 ± 0.00083	74-88-4*590
Hydrogen difluoride cation	[FFH]+ (g)	1175.5	1172.6	± 2.0	kJ/mol	39.004198 ± 0.000070	126950-54-70
Difluoromethylene	CF2 (g, triplet)	43.32	44.04	± 0.42	kJ/mol	50.00751 ± 0.00080	2154-59-8*1
Difluoromethylene	CF2 (g, singlet)	-193.87	-193.39	± 0.42	kJ/mol	50.00751 ± 0.00080	2154-59-8*2
Ethyl iodide	CH3CH2I (l)	-9.44	-39.31	± 0.49	kJ/mol	155.9656 ± 0.0016	75-03-6*500
Fluoro(fluorooxy)methylene	FCOF (g, cis)	-135.8	-137.0	± 2.0	kJ/mol	66.00691 ± 0.00085	479587-30-9*2
Dibromophosgene	COBr2 (g)	-98.05	-113.98	± 0.37	kJ/mol	187.8181 ± 0.0022	593-95-3*0
Iodide	I- (aq)		-56.826	± 0.090	kJ/mol	126.905019 ± 0.000030	20461-54-5*800
Nitrosyl ion	[NO]+ (g)	984.454	984.449	± 0.064	kJ/mol	30.00559 ± 0.00031	14452-93-8*0
Benzene	C6H6 (cr,l)	50.80	49.26	± 0.25	kJ/mol	78.1118 ± 0.0048	71-43-2*500
Bromonium	Br+ (g)	1257.774	1251.712	± 0.056	kJ/mol	79.9035 ± 0.0010	22541-56-6*0
(E)-Diazene cation	[HNNH]+ (g, trans)	1132.60	1125.69	± 0.74	kJ/mol	30.02881 ± 0.00020	59952-06-6*0
(E)-Diazene anion	[HNNH]- (g, trans)	269.3	262.4	± 1.7	kJ/mol	30.02991 ± 0.00020	59952-06-60
(Z)-Diazene	HNNH (g, cis)	229.61	222.47	± 0.83	kJ/mol	30.02936 ± 0.00020	15626-42-3*0
Diazenyl	N2H (g)	252.40	249.49	± 0.55	kJ/mol	29.02142 ± 0.00016	36882-13-0*0
Hydroxyaminiumyl	[NOH]+ (g)	1160.2	1157.2	± 1.5	kJ/mol	31.01353 ± 0.00032	63559-88-6*0
Hydroxyamidogen	HNOH (g, cis)	123.5	117.0	± 1.4	kJ/mol	32.02202 ± 0.00034	13940-32-4*2
Hydroxyaminylium	[HNOH]+ (g, trans)	1020.2	1013.0	± 2.0	kJ/mol	32.02147 ± 0.00034	66097-71-0*1
2-Hydrotrioxy anion	[OO(H)O]- (g)	27.6	21.9	± 1.2	kJ/mol	49.00669 ± 0.00090	89965-38-80
Peroxynitrous acid	HOONO (g, cis, perp)	-0.58	-7.63	± 0.53	kJ/mol	63.01288 ± 0.00091	14691-52-2*2
Dioxiranylidene	C(OO) (g)	189.0	189.8	± 1.8	kJ/mol	44.0095 ± 0.0010	138832-57-2*0
Fluorosyl ion	[FO]+ (g)	1342.41	1342.36	± 0.83	kJ/mol	34.99725 ± 0.00030	12763-67-6*0
Hydroxyde	[OH]- (aq)		-230.010	± 0.029	kJ/mol	17.00789 ± 0.00031	14280-30-9*800
Methylene anion	[CH2]- (g)	328.59	329.02	± 0.51	kJ/mol	14.02713 ± 0.00081	50928-07-9*0
Deuterium atom	D (g)	219.804	221.717	± 0.000	kJ/mol	2.01410177800 ± 0.00000000040	16873-17-9*0
Aminomethylium	[CH2NH2]+ (g)	764.1	752.1	± 1.8	kJ/mol	30.04865 ± 0.00085	488821-23-4*0
Aminomethylene	HCNH2 (g)	246.6	238.9	± 1.7	kJ/mol	29.04126 ± 0.00083	35430-17-2*0
Methylimidogen	H3CN (g)	323.8	316.0	± 1.6	kJ/mol	29.04126 ± 0.00083	27770-42-9*0
Methyleneamidogen anion	[H2CN]- (g)	193.1	189.3	± 1.2	kJ/mol	28.03387 ± 0.00082	28892-56-0*0
Hypoiodite	[IO]- (g)	-102.5	-104.4	± 1.2	kJ/mol	142.90442 ± 0.00030	15065-65-3*0
Aminomethylidyne	CNH2 (g)	372.3	368.8	± 1.5	kJ/mol	28.03332 ± 0.00082	84654-89-7*0
Cyano cation	[CN]+ (g)	1779.2	1782.7	± 1.5	kJ/mol	26.01689 ± 0.00080	12539-57-0*0
Cyanide	[CN]- (g)	63.966	67.252	± 0.098	kJ/mol	26.01799 ± 0.00080	57-12-5*0
Methanol cation	[CH3OH]+ (g)	856.96	846.28	± 0.34	kJ/mol	32.04131 ± 0.00090	12538-91-9*0
Hydroxymethylene	HCOH (g, gauche triplet)	219.1	216.0	± 1.4	kJ/mol	30.02598 ± 0.00087	19710-56-6*3
Hydroxymethylene anion	[HCOH]- (g, trans)	148.3	145.3	± 1.8	kJ/mol	30.02653 ± 0.00087	207914-87-2*1
Isoformyl	COH (g)	217.60	217.99	± 0.70	kJ/mol	29.01804 ± 0.00086	71080-92-7*0
Hydroxymethyliumylidene	[COH]+ (g)	986.03	987.67	± 0.83	kJ/mol	29.01749 ± 0.00086	60528-75-8*0
Propylium	[CH3CH2CH2]+ (g)	857.19	838.97	± 0.84	kJ/mol	43.0871 ± 0.0024	19252-52-9*0
Water dimer	(H2O)2 (g)	-491.076	-499.116	± 0.052	kJ/mol	36.03056 ± 0.00066	25655-83-8*0
iso-Propylium	[CH3CHCH3]+ (g)	823.28	806.02	± 0.30	kJ/mol	43.0871 ± 0.0024	19252-53-0*0
Cycloprop-1-enyl	CH2(CHC) (g)	528.17	523.59	± 0.78	kJ/mol	39.0559 ± 0.0024	19528-44-0*0
Cycloprop-2-enyl	CH(CHCH) (g)	491.09	486.47	± 0.77	kJ/mol	39.0559 ± 0.0024	28933-84-8*0
Cyclopropenylidene	C(CHCH) (g)	497.09	496.14	± 0.47	kJ/mol	38.0480 ± 0.0024	16165-40-5*0
2-Propynylidyne anion	[CCCH]- (g)	540.13	544.98	± 0.86	kJ/mol	37.0406 ± 0.0024	82893-67-2*0
Cyclopropynyl	CH(CC) (g)	710.8	714.9	± 1.1	kJ/mol	37.0400 ± 0.0024	119178-99-3*0
n-Butyl	CH3CH2CH2CH2 (g)	101.5	78.3	± 1.0	kJ/mol	57.1143 ± 0.0033	2492-36-6*0
Vinyl alcohol cation	[CH2CHOH]+ (g, syn)	787.3	776.1	± 1.1	kJ/mol	44.0520 ± 0.0017	57239-63-1*1
Vinoxy cation	[CH2CHO]+ (g, triplet)	1020.1	1013.1	± 1.6	kJ/mol	43.0441 ± 0.0016	35731-40-91
Vinoxide	[CH2CHO]- (g)	-153.52	-160.57	± 0.77	kJ/mol	43.0452 ± 0.0016	35731-40-9*0
Ketene	CH2CO (g, singlet)	-45.44	-48.56	± 0.15	kJ/mol	42.0367 ± 0.0016	463-51-4*2
COC vdW	(CO)(C) (g, triplet)	589.1	597.8	± 1.8	kJ/mol	40.0208 ± 0.0016	12071-24-81
Oxirene	O(CHCH) (g, singlet)	276.6	276.0	± 3.1	kJ/mol	42.0367 ± 0.0016	157-18-6*2
Oxirene	O(CHCH) (g, c-triplet)	391.9	387.8	± 2.8	kJ/mol	42.0367 ± 0.0016	157-18-6*12
Methylperoxy anion	[CH3OO]- (g)	-90.23	-100.37	± 0.99	kJ/mol	47.0339 ± 0.0010	35683-44-4*0
Dioxymethyl	H2COO (g)	113.6	106.6	± 1.2	kJ/mol	46.0254 ± 0.0010	56077-92-0*0
Formyloxoniumylidene	[HC(O)O]+ (g)	1017.0	1013.5	± 1.2	kJ/mol	45.0169 ± 0.0010	54375-27-8*0
Cyanic acid	HOCN (g)	-12.2	-14.8	± 1.0	kJ/mol	43.02478 ± 0.00086	420-05-3*0
Fulminic acid	HONC (g)	234.7	233.2	± 1.1	kJ/mol	43.02478 ± 0.00086	506-85-4*0
Cyanato cation	[NCO]+ (g)	1261.57	1262.34	± 0.59	kJ/mol	42.01629 ± 0.00086	17247-99-3*0
Isocyanate	[NCO]- (g)	-221.24	-221.36	± 0.57	kJ/mol	42.01739 ± 0.00086	71000-82-3*0
Nitrosomethylidyne	CNO (g)	388.6	390.0	± 1.7	kJ/mol	42.01684 ± 0.00086	82267-15-0*0
Oxazirinyl	C(NO) (g)	450.6	451.5	± 1.7	kJ/mol	42.01684 ± 0.00086	228850-18-8*0
Azido radical	N3 (g)	452.51	449.92	± 0.73	kJ/mol	42.02022 ± 0.00021	12596-60-0*0
Methyl formate	HC(O)OCH3 (g, anti-eclipsed)	-324.7	-337.2	± 1.8	kJ/mol	60.0520 ± 0.0017	107-31-3*2
Dimethylamine	(CH3)2NH (g)	6.02	-15.88	± 0.69	kJ/mol	45.0837 ± 0.0017	124-40-3*0
Trimethylamine	(CH3)3N (g)	4.54	-24.02	± 0.64	kJ/mol	59.1103 ± 0.0025	75-50-3*0
Isocyanogen	CNCN (g)	410.7	413.1	± 1.6	kJ/mol	52.0349 ± 0.0016	83951-85-3*0
Diisocyanogen	CNNC (g)	610.1	613.0	± 1.7	kJ/mol	52.0349 ± 0.0016	78800-21-2*0
Oxywater	(H2O)O (g)	65.0	58.5	± 1.2	kJ/mol	34.01468 ± 0.00062	171363-09-0*0
Nitroxyl	NO3 (g)	79.35	74.09	± 0.19	kJ/mol	62.00494 ± 0.00090	12033-49-7*0
Difluorodibromomethane	CF2Br2 (g)	-366.6	-384.2	± 1.4	kJ/mol	209.8155 ± 0.0022	75-61-6*0
Dichlorodibromomethane	CCl2Br2 (g)	19.2	3.6	± 1.5	kJ/mol	242.7241 ± 0.0028	594-18-3*0
Bromodifluoromethane	CHF2Br (g)	-411.03	-424.23	± 0.50	kJ/mol	130.9194 ± 0.0013	1511-62-2*0
Hydrogen fluoride	HF (aq, 40 H2O)		-321.16	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*821
1,2-Difluoroacetylene	FCCF (g)	1.4	4.3	± 1.3	kJ/mol	62.0182 ± 0.0016	689-99-6*0
Fluoro(fluorooxy)methylene	FCOF (g, trans)	-38.9	-40.4	± 1.9	kJ/mol	66.00691 ± 0.00085	479587-30-9*1
2-Hydrotrioxy cation	[OO(H)O]+ (g)	1297.8	1291.2	± 1.3	kJ/mol	49.00559 ± 0.00090	74241-49-90
Trioxidaniumyl	[HOOOH]+ (g, t, t)	927.1	917.8	± 1.4	kJ/mol	50.01353 ± 0.00091	161321-37-5*2
Triiodide ion	[I3]- (aq)		-51.46	± 0.83	kJ/mol	380.713959 ± 0.000090	14900-04-0*800
Phenylium	[C6H5]+ (g, triplet)	1251.7	1239.6	± 3.3	kJ/mol	77.1034 ± 0.0048	17333-73-2*1
Chlorobenzene cation	[C6H5Cl]+ (g)	942.52	928.60	± 0.61	kJ/mol	112.5561 ± 0.0049	55450-32-3*0
Chlorobenzene	C6H5Cl (cr,l)		11.27	± 0.59	kJ/mol	112.5566 ± 0.0049	108-90-7*500
Bromobenzene cation	[C6H5Br]+ (g)	995.1	973.8	± 1.3	kJ/mol	157.0074 ± 0.0049	55450-33-4*0
Iodobenzene	C6H5I (cr,l)	113.0	113.1	± 1.1	kJ/mol	204.0084 ± 0.0048	591-50-4*500
1,2-Dichloroethane	(CClH2)2 (g)	-118.17	-130.11	± 0.59	kJ/mol	98.9586 ± 0.0024	107-06-2*0
Fluorochlorate	[ClF]- (g)	-257.9	-257.3	± 3.8	kJ/mol	54.45165 ± 0.00090	12272-56-9*0
Nitrosyl chloride	ClNO (g)	54.420	52.518	± 0.066	kJ/mol	65.45884 ± 0.00095	2696-92-6*0
Carbon atom anion	C- (g)	589.618	594.765	± 0.055	kJ/mol	12.01125 ± 0.00080	14337-00-9*0
Dioxymethylidyne	COO (g)	295.1	296.3	± 2.1	kJ/mol	44.0095 ± 0.0010	791121-04-5*0
Carbon monoxide cation	[CO]+ (g)	1238.308	1241.588	± 0.026	kJ/mol	28.00955 ± 0.00085	12144-04-6*0
Propynylidyne cation	[C(CC)]+ (g)	1954.9	1962.0	± 2.3	kJ/mol	36.0316 ± 0.0024	154702-35-9*0
Dioxaziridinyl	N(OO) (g)	354.3	351.8	± 1.4	kJ/mol	46.00554 ± 0.00060	66252-29-7*0
Ethylene cation	[C2H4]+ (g)	1075.37	1068.22	± 0.14	kJ/mol	28.0526 ± 0.0016	34470-02-5*0
Peroxyimidogen	NOO (g)	409.8	407.9	± 1.7	kJ/mol	46.00554 ± 0.00060	60488-31-50
Aminomethyl	CH2NH2 (g)	159.6	148.7	± 1.1	kJ/mol	30.04920 ± 0.00085	10507-29-6*0
Methylamidogen	CH3NH (g)	187.81	177.08	± 0.89	kJ/mol	30.04920 ± 0.00085	15622-51-2*0
Oxadiazirine	O(NN) (g)	352.5	350.6	± 1.8	kJ/mol	44.01288 ± 0.00033	227934-45-4*0
Iminomethyl anion	[HCNH]- (g, trans)	239.0	235.2	± 2.0	kJ/mol	28.03387 ± 0.00082	90623-30-6*1
Hydrogen fluoride	HF (aq, 22 H2O)		-321.09	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*902
Hydrogen isocyanide	HNC (g)	191.57	191.96	± 0.57	kJ/mol	27.02538 ± 0.00081	6914-07-4*0
Dioxygenyl ion monohydrate	[(H2O)(O2)]+ (g)	828.6	821.8	± 1.9	kJ/mol	50.01353 ± 0.00091	11083-61-7*0
Hydrogen fluoride	HF (aq, 35 H2O)		-321.14	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*904
Ammonia	NH3 (aq, undissoc)		-80.893	± 0.053	kJ/mol	17.03056 ± 0.00022	7664-41-7*1000
Methyleneoxonium	CH2OH2 (g)	158.0	149.2	± 4.1	kJ/mol	32.04186 ± 0.00090	177788-17-9*0
Trihydrogen dioxide anion	[HOHOH]- (g)	-487.1	-495.4	± 1.0	kJ/mol	35.02317 ± 0.00064	12501-19-8*0
NON	NON (g)	543.8	540.6	± 1.8	kJ/mol	44.01288 ± 0.00033	227934-46-5*0
Bifluoride	[FHF]- (g)	-710.3	-714.1	± 2.4	kJ/mol	39.005295 ± 0.000070	18130-74-0*0
2-Propynylium	[CH2CCH]+ (g)	1193.34	1190.53	± 0.39	kJ/mol	39.0554 ± 0.0024	21540-27-2*0
Hydrogen fluoride	HF (aq, 50 H2O)		-321.19	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*822
2-Cyclopropen-1-ylium-1-yl	[C(CHCH)]+ (g)	1382.0	1381.0	± 1.2	kJ/mol	38.0474 ± 0.0024	85398-75-0*0
Trifluoromethide	[CF3]- (g)	-638.3	-640.2	± 1.9	kJ/mol	69.00646 ± 0.00080	54128-17-5*0
Propenediylidene	CHCHC (g)	796.1	797.2	± 1.3	kJ/mol	38.0480 ± 0.0024	60731-11-5*0
Isobutane	CH3CH(CH3)2 (g)	-106.67	-135.27	± 0.37	kJ/mol	58.1222 ± 0.0033	75-28-5*0
Chloride	Cl- (aq)		-166.993	± 0.023	kJ/mol	35.45325 ± 0.00090	16887-00-6*800
1-Hydroxyethylium	[CH3CHOH]+ (g)	609.20	594.78	± 0.40	kJ/mol	45.0600 ± 0.0017	18682-96-7*0
Acetaldehyde cation	[CH3CHO]+ (g)	831.99	822.01	± 0.31	kJ/mol	44.0520 ± 0.0017	36505-03-0*0
Nitrosyl nitrite	ONONO (g, t, c)	108.3	104.2	± 1.8	kJ/mol	76.01168 ± 0.00091	122413-35-8*2
Oxiranylium	[CH2(CHO)]+ (g, triplet)	1233.7	1226.7	± 1.8	kJ/mol	43.0441 ± 0.0016	57789-76-1*1
Oxiranyl anion	[CH2(CHO)]- (g)	121.4	113.3	± 1.6	kJ/mol	43.0452 ± 0.0016	72722-59-9*0
Ethynol anion	[HCCO]- (g)	-48.59	-47.34	± 0.87	kJ/mol	41.0293 ± 0.0016	64066-01-9*0
Dicarbon monoxide anion	[CCO]- (g)	152.6	156.3	± 1.4	kJ/mol	40.0213 ± 0.0016	87191-88-6*0
Nitrogen atom cation	N+ (g)	1872.901	1875.682	± 0.024	kJ/mol	14.006191 ± 0.000070	14158-23-7*0
Dicarbon monoxide cation	[CCO]+ (g)	1431.6	1436.7	± 2.2	kJ/mol	40.0203 ± 0.0016	12287-08-0*0
COC vdW	(CO)(C) (g, singlet)	726.4	734.8	± 1.7	kJ/mol	40.0208 ± 0.0016	12071-24-82
C=O-C cation	[COC]+ (g, doublet)	1575.9	1583.0	± 2.3	kJ/mol	40.0203 ± 0.0016	83483-98-1*1
C=O=C anion	[COC]- (g)	550.5	554.2	± 2.1	kJ/mol	40.0213 ± 0.0016	87191-88-60
Dioxygen anion	[O2]- (g)	-43.38	-42.74	± 0.17	kJ/mol	31.99935 ± 0.00060	11062-77-4*0
Formic acid cation	[HC(O)OH]+ (g, anti)	723.7	716.7	± 1.4	kJ/mol	46.0248 ± 0.0010	50614-05-6*2
Formic acid anion	[HC(O)OH]- (g, syn)	-254.5	-260.7	± 2.2	kJ/mol	46.0259 ± 0.0010	19066-82-1*1
Dibromine monoxide	BrOBr (g)	120.9	104.4	± 1.4	kJ/mol	175.8074 ± 0.0020	21308-80-5*0
OH-CO vdW complex	(OH)(CO) (g, vdW)	-80.30	-77.41	± 0.96	kJ/mol	45.0174 ± 0.0010	2564-85-4100
CO-HO vdW complex	(CO)(HO) (g, vdW)	-77.6	-73.6	± 1.8	kJ/mol	45.0174 ± 0.0010	2564-84-3100
H-CO2 vdW complex	(H)(CO2) (g, vdW)	-179.3	-178.4	± 2.2	kJ/mol	45.0174 ± 0.0010	2564-83-2100
Isocyanic acid cation	[HNCO]+ (g)	1002.82	1000.40	± 0.56	kJ/mol	43.02423 ± 0.00086	444010-28-0*0
Isofulminic acid cation	[HCNO]+ (g)	1215.5	1212.7	± 1.6	kJ/mol	43.02423 ± 0.00086	114766-65-3*0
Acetic acid	CH3C(O)OH (aq, 1500 H2O)		-484.90	± 0.23	kJ/mol	60.0520 ± 0.0017	64-19-7*840
Acetyl chloride	CH3C(O)Cl (l)		-272.21	± 0.33	kJ/mol	78.4973 ± 0.0019	75-36-5*500
Glyoxal	(CHO)2 (g, trans)	-206.84	-212.48	± 0.59	kJ/mol	58.0361 ± 0.0017	107-22-2*1
Ammonium nitrate	(NH4)NO3 (cr,l)	-350.26	-365.22	± 0.19	kJ/mol	80.04344 ± 0.00095	6484-52-2*500
Diazoethenylidene	NNCC (g)	656.9	659.5	± 3.0	kJ/mol	52.0349 ± 0.0016	130760-10-0*0
Isocyanomethylidyne	CNC (g)	671.3	675.7	± 3.6	kJ/mol	38.0281 ± 0.0016	53590-27-5*0
Tetrachloromethane	CCl4 (l)	-110.59	-130.00	± 0.74	kJ/mol	153.8215 ± 0.0037	56-23-5*500
Chloroform	CCl3H (l)		-133.92	± 0.64	kJ/mol	119.3767 ± 0.0028	67-66-3*590
Fluorotribromomethane	CBr3F (g)	-108.0	-132.0	± 1.6	kJ/mol	270.7211 ± 0.0031	353-54-8*0
Chlorotribromomethane	CBr3Cl (g)	76.1	53.3	± 1.6	kJ/mol	287.1754 ± 0.0032	594-15-0*0
Hydroxyimidogen	NOH (g)	217.40	214.52	± 0.95	kJ/mol	31.01408 ± 0.00032	35337-59-8*0
Water	H2O (l)		-285.825	± 0.026	kJ/mol	18.01528 ± 0.00033	7732-18-5*590
Fluoromethyliumylidene	[CF]+ (g)	1122.56	1125.78	± 0.49	kJ/mol	31.00855 ± 0.00080	33412-11-2*0
Fluoromethylene	CHF (g)	148.34	148.62	± 0.46	kJ/mol	32.01704 ± 0.00080	13453-52-6*0
Ethyl iodide	CH3CH2I (g)	8.67	-7.21	± 0.49	kJ/mol	155.9656 ± 0.0016	75-03-6*0
Nitrous acid	HONO (g, cis)	-71.41	-77.76	± 0.33	kJ/mol	47.01348 ± 0.00061	7782-77-6*2
Hydroxyoxoammoniumyl	[HONO]+ (g, trans)	983.6	977.2	± 1.7	kJ/mol	47.01293 ± 0.00061	80371-48-8*1
1,2-Dichloroacetylene	ClCCCl (g)	230.4	233.7	± 1.9	kJ/mol	94.9268 ± 0.0024	7572-29-4*0
1,2-Dibromoacetylene	BrCCBr (g)	332.9	322.0	± 3.6	kJ/mol	183.8294 ± 0.0026	624-61-3*0
Fluoro(fluorooxy)methylene	FCOF (g, vdW triplet)	-101.0	-99.2	± 2.0	kJ/mol	66.00691 ± 0.00085	479587-30-9*101
Dibromide	[Br2]- (g)	-200.1	-214.2	± 2.0	kJ/mol	159.8085 ± 0.0020	12595-70-9*0
Fluorooxomethylium	[FCO]+ (g)	724.2	723.8	± 1.5	kJ/mol	47.00795 ± 0.00085	38264-00-5*0
Fluoroisoformyl	COF (g)	-39.2	-33.8	± 1.8	kJ/mol	47.00850 ± 0.00085	1871-24-50
Aminylium	[NH2]+ (g)	1266.50	1263.78	± 0.18	kJ/mol	16.02207 ± 0.00016	15194-15-7*0
Benzene cation	[C6H6]+ (g)	992.59	976.13	± 0.26	kJ/mol	78.1113 ± 0.0048	34504-50-2*0
Hydrogen nitroxylate	[HONO]- (g, cis)	-107.8	-112.4	± 2.0	kJ/mol	47.01403 ± 0.00061	24388-53-2*2
o-Benzyne	C6H4 (g)	469.7	460.8	± 1.4	kJ/mol	76.0960 ± 0.0048	462-80-6*0
o-Benzyne anion	[C6H4]- (g)	415.6	407.0	± 1.5	kJ/mol	76.0965 ± 0.0048	100569-88-8*0
Chlorine atom cation	Cl+ (g)	1370.806	1372.602	± 0.0021	kJ/mol	35.45215 ± 0.00090	24203-47-2*0
Hydroxydioxonitrate	[HNO3]- (g)	-191.2	-195.5	± 2.9	kJ/mol	63.01343 ± 0.00091	58875-09-5*0
1,2-Dibromoethane	(CBrH2)2 (g)	-10.8	-37.6	± 1.3	kJ/mol	187.8612 ± 0.0026	106-93-4*0
1,1-Difluoroethane	CHF2CH3 (g)	-486.7	-500.4	± 5.7	kJ/mol	66.0500 ± 0.0016	75-37-6*0
1,1-Dichloroethane	CHCl2CH3 (g)	-114.7	-127.4	± 1.1	kJ/mol	98.9586 ± 0.0024	75-34-3*0
Hydrogen fluoride	HF (aq, 18 H2O)		-321.06	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*901
Dioxaziridinyl anion	[N(OO)]- (g)	295.5	293.0	± 1.5	kJ/mol	46.00609 ± 0.00060	66252-31-1*0
Ethylidyne	CH3C (g, quartet)	641.2	636.7	± 1.8	kJ/mol	27.0452 ± 0.0016	67624-57-1*2
Acetylene anion	[HCCH]- (g, trans)	359.5	359.3	± 3.0	kJ/mol	26.0378 ± 0.0016	50443-89-5*1
Peroxyimidogen anion	[NOO]- (g)	162.9	160.6	± 1.6	kJ/mol	46.00609 ± 0.00060	60488-31-5*0
Methylammonium	[CH3NH3]+ (g)	628.8	609.7	± 2.5	kJ/mol	32.06453 ± 0.00091	17000-00-9*0
Nitric acid	HNO3 (aq, 1000 H2O)		-206.28	± 0.19	kJ/mol	63.01288 ± 0.00091	7697-37-2*839
Nirous oxide cation	[NNO]+ (g)	1329.68	1326.78	± 0.12	kJ/mol	44.01233 ± 0.00033	12269-46-4*0
Iminomethyl anion	[HCNH]- (g, cis)	254.3	250.5	± 2.0	kJ/mol	28.03387 ± 0.00082	90623-30-6*2
Hydrogen cyanide cation	[HCN]+ (g)	1442.53	1442.06	± 0.21	kJ/mol	27.02483 ± 0.00081	12601-62-6*0
Hydrogen peroxide cation	[H2O2]+ (g, cis)	930.90	924.04	± 0.94	kJ/mol	34.01413 ± 0.00062	12325-10-9*2
Methyleneoxonium cation	[CH2OH2]+ (g)	829.9	819.7	± 4.5	kJ/mol	32.04131 ± 0.00090	177788-17-90
Oxadiazirine anion	[O(NN)]- (g)	99.7	100.0	± 2.6	kJ/mol	44.01343 ± 0.00033	350586-31-1*0
Hydroxymethylide	[CH2OH]- (g)	9.6	3.0	± 1.8	kJ/mol	31.03447 ± 0.00088	55830-71-2*0
Formaldehyde cation	[H2CO]+ (g)	945.26	941.73	± 0.13	kJ/mol	30.02543 ± 0.00087	54288-05-0*0
(Z)-Diazene cation	[HNNH]+ (g, cis)	1157.3	1150.5	± 1.4	kJ/mol	30.02881 ± 0.00020	86631-37-0*0
Hydroxymethylene cation	[HCOH]+ (g, cis)	987.0	983.4	± 1.7	kJ/mol	30.02543 ± 0.00087	135395-06-1*2
Hydroxymethylene cation	[HCOH]+ (g, gauche quartet)	1481.9	1479.1	± 2.1	kJ/mol	30.02543 ± 0.00087	135395-06-1*3
(Z)-Diazene anion	[HNNH]- (g, cis)	284.1	277.6	± 1.7	kJ/mol	30.02991 ± 0.00020	86631-37-00
Hydroxymethylene anion	[HCOH]- (g, cis)	161.6	159.7	± 1.9	kJ/mol	30.02653 ± 0.00087	207914-87-2*2
Hydroxymethylene anion	[HCOH]- (g, gauche quartet)	333.7	333.0	± 2.5	kJ/mol	30.02653 ± 0.00087	207914-87-2*3
Aquacarbon	H2OC (g, triplet)	441.4	439.5	± 2.1	kJ/mol	30.02598 ± 0.00087	81434-73-3*1
Aquacarbon	H2OC (g, singlet vdW)	470.2	467.5	± 2.4	kJ/mol	30.02598 ± 0.00087	81434-73-3*102
Dioxygen difluoride cation	[FOOF]+ (g, trans)	1293.0	1289.1	± 4.6	kJ/mol	69.99506 ± 0.00060	7783-44-01
Isoformyl anion	[COH]- (g)	50.8	53.4	± 2.7	kJ/mol	29.01859 ± 0.00086	81747-63-9*0
1-Hydrazinylium-1-yl	[H2NN]+ (g)	1145.2	1138.2	± 1.5	kJ/mol	30.02881 ± 0.00020	63986-30-1*0
Isodiazene anion	[H2NN]- (g)	387.1	380.3	± 1.8	kJ/mol	30.02991 ± 0.00020	63986-30-10
Trioxidaniumyl	[HOOOH]+ (g, c, t)	937.1	928.0	± 1.4	kJ/mol	50.01353 ± 0.00091	161321-37-5*3
Hydrogen bromide	HBr (aq, 600 H2O)		-120.47	± 0.15	kJ/mol	80.9119 ± 0.0010	10035-10-6*834
Hydrogen bromide	HBr (aq, 5000 H2O)		-120.77	± 0.15	kJ/mol	80.9119 ± 0.0010	10035-10-6*844
Propynylidene cation	[HCCCH]+ (g)	1410.8	1413.4	± 1.2	kJ/mol	38.0474 ± 0.0024	75123-91-0*0
Propynylidene	HCCCH (g, cis singlet)	597.8	599.6	± 1.5	kJ/mol	38.0480 ± 0.0024	67152-18-5*3
Propadienylidenide	[CH2CC]- (g)	381.24	382.14	± 0.44	kJ/mol	38.0485 ± 0.0024	109292-49-1*0
1,2-Propadien-1-ylium-1-yl	[CH2CC]+ (g)	1561.7	1562.9	± 1.4	kJ/mol	38.0474 ± 0.0024	110714-00-6*0
1,5-Hexadiene	CH2CHCH2CH2CHCH2 (g)	108.34	83.75	± 0.40	kJ/mol	82.1436 ± 0.0049	592-42-7*0
Nitric acid	HNO3 (cr,l)	-178.98	-173.25	± 0.19	kJ/mol	63.01288 ± 0.00091	7697-37-2*500
Trioxodinitrate anion	[ONNO2]- (g, vdW)	-103.0	-106.9	± 2.9	kJ/mol	76.01223 ± 0.00091	194856-62-7*100
2-Hydroxyethylium	[CH2CH2OH]+ (g, gauche)	1024.7	1012.2	± 2.3	kJ/mol	45.0600 ± 0.0017	38607-31-7*1
Hydrogen chloride	HCl (aq, 100 H2O)		-165.759	± 0.025	kJ/mol	36.46064 ± 0.00090	7647-01-0*828
Ethoxy	CH3CH2O (g)	1.67	-11.76	± 0.52	kJ/mol	45.0605 ± 0.0017	2154-50-9*0
Ethyloxoniumylidene	[CH3CH2O]+ (g)	988.9	975.2	± 1.8	kJ/mol	45.0600 ± 0.0017	54387-07-4*0
Dihydrogen cation	[H2]+ (g)	1488.364	1488.480	± 0.000	kJ/mol	2.01533 ± 0.00014	12184-90-6*0
Carbon dioxide	CO2 (g, triplet)	48.9	49.6	± 2.4	kJ/mol	44.0095 ± 0.0010	124-38-9*1
Formylmethyl anion	[CH2CHO]- (g, perp triplet)	140.6	134.3	± 1.9	kJ/mol	43.0452 ± 0.0016	64723-93-9*0
Hydroxylamine	NH2OH (g, cis)	-14.7	-25.2	± 1.5	kJ/mol	33.02996 ± 0.00037	7803-49-8*2
Nitrosyl nitrite anion	[ONONO]- (g, sym)	-100.8	-104.0	± 4.4	kJ/mol	76.01223 ± 0.00091	122413-35-81
C=O-C cation	[COC]+ (g, quartet)	1812.2	1816.3	± 2.3	kJ/mol	40.0203 ± 0.0016	83483-98-1*2
Hydroxylamine cation	[NH2OH]+ (g)	858.0	848.1	± 1.8	kJ/mol	33.02941 ± 0.00037	62675-55-2*0
Oxirene cation	[O(CHCH)]+ (g)	1109.7	1106.2	± 5.2	kJ/mol	42.0361 ± 0.0016	94664-69-4*0
Hydrogen fluoride	HF (l)		-302.43	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*590
2,4,5-Trioxa-1,3-diazabicyclo[1.1.1]pentane	N(O3)N (g)	602.6	593.4	± 2.0	kJ/mol	76.01168 ± 0.00091	224950-18-9*0
Formic acid anion	[HC(O)OH]- (g, anti)	-239.4	-245.1	± 2.4	kJ/mol	46.0259 ± 0.0010	19066-82-1*2
Dinitrogen tetraoxide	O2NNO2 (g)	20.09	10.80	± 0.14	kJ/mol	92.0111 ± 0.0012	10544-72-6*0
Dioxirane cation	[H2C(OO)]+ (g)	1051.3	1043.7	± 2.2	kJ/mol	46.0248 ± 0.0010	232262-10-1*0
Dioxymethyl cation	[H2COO]+ (g)	1076.0	1069.2	± 1.9	kJ/mol	46.0248 ± 0.0010	232262-11-2*0
Hydrogen fluoride	HF (aq, 10 H2O)		-320.91	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*815
Dioxymethylene	HCOO (g, cis)	332.1	329.9	± 5.9	kJ/mol	45.0174 ± 0.0010	438586-67-5*2
2-Cyclopropyn-1-ylidene	C(CC) (g, triplet)	905.6	912.5	± 2.0	kJ/mol	36.0321 ± 0.0024	102508-15-6*1
Oxygen atom	O (g, singlet)	436.666	438.523	± 0.0021	kJ/mol	15.99940 ± 0.00030	17778-80-2*2
Dioxygenyl fluoride cation	[FOO]+ (g)	1215.2	1212.7	± 3.0	kJ/mol	50.99665 ± 0.00060	139584-95-5*0
Nitroxyl cation	[H2NO]+ (g)	946.31	939.18	± 0.84	kJ/mol	32.02147 ± 0.00034	51375-41-80
Nitrosomethyliumylidene	[CNO]+ (g)	1509.5	1511.8	± 2.0	kJ/mol	42.01629 ± 0.00086	67197-19-7*0
Fulminate	[CNO]- (g)	59.4	59.6	± 2.0	kJ/mol	42.01739 ± 0.00086	28269-67-2*0
Acetic acid	CH3C(O)OH (l)	-484.09	-483.66	± 0.18	kJ/mol	60.0520 ± 0.0017	64-19-7*500
Acetic acid	CH3C(O)OH (aq)		-485.17	± 0.23	kJ/mol	60.0520 ± 0.0017	64-19-7*800
Acetic acid	CH3C(O)OH (aq, 75 H2O)		-484.70	± 0.23	kJ/mol	60.0520 ± 0.0017	64-19-7*825
Acetic acid	CH3C(O)OH (aq, 700 H2O)		-484.88	± 0.23	kJ/mol	60.0520 ± 0.0017	64-19-7*835
Hydrogen chloride	HCl (aq, 2000 H2O)		-166.684	± 0.024	kJ/mol	36.46064 ± 0.00090	7647-01-0*841
Methane cation	[CH4]+ (g)	1150.93	1143.81	± 0.27	kJ/mol	16.04191 ± 0.00085	20741-88-2*0
Glyoxal	(CHO)2 (g, cis)	-188.41	-193.86	± 0.73	kJ/mol	58.0361 ± 0.0017	107-22-2*2
Glyoxal	(CHO)2 (g)	-206.84	-212.40	± 0.59	kJ/mol	58.0361 ± 0.0017	107-22-2*0
Hydroxyaminylium	[HNOH]+ (g, cis)	1049.2	1042.1	± 2.0	kJ/mol	32.02147 ± 0.00034	66097-71-0*2
Hydroxyamidogen anion	[HNOH]- (g)	91.2	85.4	± 2.1	kJ/mol	32.02257 ± 0.00034	66097-71-00
Isocyanogen anion	[CNCN]- (g, trans)	383.9	387.6	± 2.5	kJ/mol	52.0354 ± 0.0016	83951-85-31
Diisocyanogen cation	[CNNC]+ (g, trans)	1823.0	1825.8	± 3.5	kJ/mol	52.0343 ± 0.0016	78800-21-21
Cyanomethylidyne	CCN (g)	676.0	680.4	± 1.9	kJ/mol	38.0281 ± 0.0016	4120-02-9*0
Azide ion	[N3]- (g)	194.2	190.6	± 1.1	kJ/mol	42.02077 ± 0.00021	14343-69-2*0
Diazomethylene	CNN (g)	580.9	581.5	± 2.4	kJ/mol	40.02418 ± 0.00081	2468-81-7*0
Trioxidanylium	[HOOO]+ (g, cis)	1084.9	1078.7	± 1.4	kJ/mol	49.00559 ± 0.00090	74241-49-9*2
Hydrogen chloride	HCl (aq, 75 H2O)		-165.558	± 0.026	kJ/mol	36.46064 ± 0.00090	7647-01-0*825
Fluorochlorobromomethane	CHFClBr (g)	-219.3	-231.7	± 5.5	kJ/mol	147.3737 ± 0.0016	593-98-6*0
Aminium	[NH3]+ (g)	944.269	937.314	± 0.030	kJ/mol	17.03001 ± 0.00022	19496-55-0*0
Fluoromethyliumyl	[CHF]+ (g)	1116.9	1117.2	± 2.1	kJ/mol	32.01649 ± 0.00080	89877-52-1*0
Fluoromethylene anion	[CHF]- (g)	95.95	96.48	± 0.63	kJ/mol	32.01759 ± 0.00080	71267-42-0*0
Hexafluoroethane	CF3CF3 (g)	-1325.5	-1333.8	± 1.2	kJ/mol	138.0118 ± 0.0016	76-16-4*0
Polytetrafluoroethylene	C2F4 (s)		-829.59	± 0.59	kJ/mol	100.0150 ± 0.0016	9002-84-0*591
Diiodide	[I2]- (g)	-178.13	-180.72	± 0.48	kJ/mol	253.809489 ± 0.000060	12190-71-5*0
Hydrogen fluoride	HF (aq, 30 H2O)		-321.13	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*820
Ethane cation	[C2H6]+ (g)	1043.54	1029.98	± 0.60	kJ/mol	30.0685 ± 0.0017	34488-65-8*0
cis-1,2-Difluoroethene	CHFCHF (g, cis)	-303.0	-309.8	± 1.1	kJ/mol	64.0341 ± 0.0016	1630-77-9*0
trans-1,2-Difluoroethene	CHFCHF (g, trans)	-299.8	-306.2	± 1.1	kJ/mol	64.0341 ± 0.0016	1630-78-0*0
Bromoacetylene	HCCBr (g)	282.4	275.9	± 2.2	kJ/mol	104.9333 ± 0.0019	593-61-3*0
Hydroxyoxoammoniumyl	[HONO]+ (g, cis)	1014.8	1008.5	± 1.8	kJ/mol	47.01293 ± 0.00061	80371-48-8*2
Formyl fluoride cation	[HFCO]+ (g)	816.3	813.0	± 1.3	kJ/mol	48.01589 ± 0.00086	99766-68-4*0
Formyl fluoride	[FCO]- (g)	-405.4	-403.9	± 1.7	kJ/mol	47.00905 ± 0.00085	62227-71-8*0
Fluoroisoformyl cation	[COF]+ (g)	1347.4	1348.8	± 2.2	kJ/mol	47.00795 ± 0.00085	1871-25-60
Hydrogen difluoride	FHF (g)	-203.6	-203.7	± 2.5	kJ/mol	39.004746 ± 0.000070	12528-21-1*0
Hydrogen fluoride	HF (aq, 60 H2O)		-321.21	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*823
Iodine atom cation	I+ (g)	1115.549	1115.149	± 0.0062	kJ/mol	126.903921 ± 0.000030	22541-93-1*0
Hydrogen nitroxylate	[HONO]- (g, trans)	-106.8	-110.7	± 2.0	kJ/mol	47.01403 ± 0.00061	24388-53-2*1
Ethylene anion	[C2H4]- (g, anti)	236.8	229.2	± 2.2	kJ/mol	28.0537 ± 0.0016	34527-91-8*1
Aminyliumyl	[NH]+ (g)	1658.99	1659.91	± 0.25	kJ/mol	15.014131 ± 0.000099	19067-62-0*0
Nitrous acid	HONO (g)	-73.047	-78.704	± 0.078	kJ/mol	47.01348 ± 0.00061	7782-77-6*0
Trifluoride ion	[F3]- (g)	-365.6	-366.6	± 2.5	kJ/mol	56.9957582 ± 0.0000015	25730-99-8*0
Water	H2O (l, eq.press.)		-285.827	± 0.026	kJ/mol	18.01528 ± 0.00033	7732-18-5*589
Aminomethyl anion	[CH2NH2]- (g)	212.1	201.1	± 2.8	kJ/mol	30.04975 ± 0.00085	74215-21-7*0
Methylaminilium	[CH3NH]+ (g)	1135.2	1125.2	± 2.5	kJ/mol	30.04865 ± 0.00085	49784-84-1*0
Hydrogen bromide	HBr (aq, 2000 H2O)		-120.67	± 0.15	kJ/mol	80.9119 ± 0.0010	10035-10-6*841
Allylium	[CH2CHCH2]+ (g)	964.26	952.70	± 0.55	kJ/mol	41.0713 ± 0.0024	1724-44-3*0
1-Propenyl cation	[CH3CHCH]+ (g, cis)	1232.7	1222.4	± 1.7	kJ/mol	41.0713 ± 0.0024	50457-58-4*2
1-Propenyl anion	[CH3CHCH]- (g, cis)	203.7	192.4	± 1.8	kJ/mol	41.0723 ± 0.0024	65887-20-9*2
Hydrogen chloride	HCl (aq, 1500 H2O)		-166.638	± 0.025	kJ/mol	36.46064 ± 0.00090	7647-01-0*840
1-Propenyl cation	[CH3CHCH]+ (g, trans)	1234.3	1223.9	± 1.7	kJ/mol	41.0713 ± 0.0024	50457-58-4*1
1-Propenyl anion	[CH3CHCH]- (g, trans)	210.2	199.1	± 1.8	kJ/mol	41.0723 ± 0.0024	65887-20-9*1
Cyclopropyl	CH(CH2CH2) (g)	301.2	288.6	± 4.7	kJ/mol	41.0718 ± 0.0024	2417-82-5*0
Hydrogen fluoride	HF (aq, 55 H2O)		-321.20	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*905
Carbon atom	C (g, singlet)	833.326	838.472	± 0.055	kJ/mol	12.01070 ± 0.00080	7440-44-0*2
Methanimine cation	[H2CNH]+ (g)	1055.9	1048.8	± 2.1	kJ/mol	29.04071 ± 0.00083	65130-65-6*0
Cycloprop-2-enylium	[CH(CHCH)]+ (g)	1080.9	1075.8	± 1.4	kJ/mol	39.0554 ± 0.0024	26810-74-2*0
Methanimine anion	[H2CNH]- (g)	228.7	221.4	± 2.5	kJ/mol	29.04181 ± 0.00083	127593-73-1*0
Propynylidene	HCCCH (g, trans singlet)	596.6	598.4	± 1.1	kJ/mol	38.0480 ± 0.0024	67152-18-5*4
Aminomethyliumyl	[HCNH2]+ (g)	1040.8	1033.1	± 2.6	kJ/mol	29.04071 ± 0.00083	89302-94-3*0
Aminomethylene anion	[HCNH2]- (g)	357.2	350.2	± 2.5	kJ/mol	29.04181 ± 0.00083	207914-86-1*0
Cyclopropyne	CH2(CC) (g)	791.1	790.6	± 1.4	kJ/mol	38.0480 ± 0.0024	60701-63-5*0
Nitrate	[NO3]- (aq)		-206.60	± 0.19	kJ/mol	62.00549 ± 0.00090	14797-55-8*800
Fluoroniumyl ion	[HF]+ (g)	1275.591	1275.823	± 0.057	kJ/mol	20.005795 ± 0.000070	12381-92-9*0
Cyclopropenyliumdiyl	[CH(CC)]+ (g)	1692.1	1695.0	± 1.9	kJ/mol	37.0395 ± 0.0024	127476-05-5*0
Cyclopropynyl anion	[CH(CC)]- (g)	517.9	520.9	± 1.1	kJ/mol	37.0406 ± 0.0024	136861-42-2*0
Diazene ion	[N2H]- (g)	176.5	175.1	± 2.2	kJ/mol	29.02197 ± 0.00016	71004-29-0*0
Hydrazinylium	[N2H3]+ (g)	969.6	958.4	± 1.2	kJ/mol	31.03675 ± 0.00025	37369-93-0*0
Ethyloxoniumyl	[CH3CH2OH]+ (g)	795.40	778.27	± 0.76	kJ/mol	46.0679 ± 0.0017	34480-55-2*0
Ethanol	CH3CH2OH (l)	-269.29	-277.05	± 0.22	kJ/mol	46.0684 ± 0.0017	64-17-5*500
Methylaminyliumyl	[H3CN]+ (g, quartet)	1478.4	1471.3	± 2.6	kJ/mol	29.04071 ± 0.00083	56924-51-7*2
Dioxygen difluoride cation	[FOOF]+ (g, cis)	1295.8	1291.7	± 4.6	kJ/mol	69.99506 ± 0.00060	7783-44-02
Methylimidogen anion	[H3CN]- (g)	322.3	314.6	± 1.7	kJ/mol	29.04181 ± 0.00083	82539-34-2*0
1-Hydroxyethyl anion	[CH3CHOH]- (g)	-19.8	-33.2	± 2.5	kJ/mol	45.0610 ± 0.0017	88032-18-2*0
Hypochlorous acid anion	[HOCl]- (g)	194.2	193.9	± 3.0	kJ/mol	52.46059 ± 0.00095	34524-94-2*0
Nirous oxide anion	[NNO]- (g)	100.3	97.7	± 1.9	kJ/mol	44.01343 ± 0.00033	12274-12-3*0
Methyleneaminylium	[H2CN]+ (g, triplet)	1457.2	1453.6	± 2.5	kJ/mol	28.03277 ± 0.00082	53518-13-1*1
Fluorine atom cation	F+ (g)	1758.335	1760.634	± 0.055	kJ/mol	18.99785462 ± 0.00000050	14701-13-4*0
Acetaldehyde anion	[CH3CHO]- (g)	-59.3	-69.8	± 2.5	kJ/mol	44.0531 ± 0.0017	60427-04-5*0
Dinitrogen cation	[N2]+ (g)	1503.311	1503.312	± 0.0011	kJ/mol	28.01293 ± 0.00014	13966-04-6*0
Trioxodinitrate anion	[ONNO2]- (g, non-vdW only)	-85.5	-92.6	± 2.7	kJ/mol	76.01223 ± 0.00091	194856-62-7*1
Hydrogen fluoride	HF (aq, 37 H2O)		-321.15	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*890
Hydrogen bromide	HBr (aq, 3000 H2O)		-120.72	± 0.15	kJ/mol	80.9119 ± 0.0010	10035-10-6*842
Fluorosyl fluoride	FFO (g)	189.2	189.6	± 4.8	kJ/mol	53.99621 ± 0.00030	86825-57-2*0
Dihydrooxooxygen cation	[(H2O)O]+ (g)	994.6	987.9	± 1.5	kJ/mol	34.01413 ± 0.00062	177329-59-8*0
Bromosyl ion	[BrO]+ (g)	1139.5	1131.7	± 1.6	kJ/mol	95.9029 ± 0.0010	142315-39-7*0
Ketene cation	[CH2CO]+ (g)	882.13	879.11	± 0.15	kJ/mol	42.0361 ± 0.0016	64999-16-2*0
Ketene anion	[CH2CO]- (g)	-14.7	-17.7	± 2.4	kJ/mol	42.0372 ± 0.0016	56391-79-8*0
Hydrogen chloride	HCl (aq, 2439 H2O)		-166.714	± 0.024	kJ/mol	36.46064 ± 0.00090	7647-01-0*951
Oxoethenylium	[HCCO]+ (g)	1139.0	1141.7	± 2.5	kJ/mol	41.0282 ± 0.0016	92056-63-8*0
Hydrogen fluoride	HF (aq, 55.51 H2O)		-321.20	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*891
Nitrosyl nitrite anion	[ONONO]- (g, t, c)	-97.4	-100.6	± 4.4	kJ/mol	76.01223 ± 0.00091	122413-35-82
Bromine dioxide	OBrO (g)	167.8	158.2	± 2.8	kJ/mol	111.9028 ± 0.0012	21255-83-4*0
Hydrogen fluoride	HF (aq, 22.2 H2O)		-321.09	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*888
Aminomethyliumylidene	[CNH2]+ (g)	1168.9	1165.7	± 2.6	kJ/mol	28.03277 ± 0.00082	86784-42-1*0
Ethynol cation	[HCCOH]+ (g)	1063.0	1060.8	± 2.5	kJ/mol	42.0361 ± 0.0016	84005-02-7*0
Methyl hydroperoxide cation	[CH3OOH]+ (g)	834.7	822.1	± 5.7	kJ/mol	48.0407 ± 0.0010	112465-88-0*0
Methoxyoxoniumylidene	[CH3OO]+ (g)	1010.9	1002.5	± 2.4	kJ/mol	47.0328 ± 0.0010	86475-50-5*0
Hydrogen cyanide anion	[HCN]- (g)	239.6	240.0	± 2.7	kJ/mol	27.02593 ± 0.00081	12334-27-9*0
Hydrogen fluoride	HF (aq, 23 H2O)		-321.09	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*903
Dioxirane anion	[H2C(OO)]- (g)	-170.5	-177.9	± 3.9	kJ/mol	46.0259 ± 0.0010	157-26-60
Ammonium chloride	(NH4)Cl (cr)	-311.730	-314.892	± 0.063	kJ/mol	53.49120 ± 0.00095	12125-02-9*510
Dioxymethyl anion	[H2COO]- (g)	57.2	51.2	± 2.5	kJ/mol	46.0259 ± 0.0010	93207-29-5*0
Formyloxy	HC(O)O (g)	-124.68	-126.04	± 0.53	kJ/mol	45.0174 ± 0.0010	16499-21-1*0
Dioxiranyl	HC(OO) (g)	216.5	213.0	± 2.0	kJ/mol	45.0174 ± 0.0010	120595-16-6*0
Dioxymethylene	HCOO (g, trans)	359.1	356.7	± 5.9	kJ/mol	45.0174 ± 0.0010	438586-67-5*1
2-Cyclopropyn-1-ylidene	C(CC) (g, singlet)	999.7	1006.5	± 2.6	kJ/mol	36.0321 ± 0.0024	102508-15-6*2
Nitrosyl nitrate	ONONO2 (g, cis)	59.5	51.8	± 2.2	kJ/mol	92.0111 ± 0.0012	15969-55-8*2
Nitrogen hydride oxide	H3NO (g)	72.3	61.1	± 1.7	kJ/mol	33.02996 ± 0.00037	38544-48-8*0
Nitroxyl anion	[H2NO]- (g)	49.3	42.3	± 1.8	kJ/mol	32.02257 ± 0.00034	51375-41-8*0
Oxazirinyl cation	[C(NO)]+ (g)	1566.7	1567.4	± 2.8	kJ/mol	42.01629 ± 0.00086	228850-18-80
Oxazirinyl anion	[C(NO)]- (g)	449.8	450.6	± 2.8	kJ/mol	42.01739 ± 0.00086	28269-68-3*0
Acetic acid	CH3C(O)OH (g, syn-anti equilib)	-418.72	-432.84	± 0.62	kJ/mol	60.0520 ± 0.0017	64-19-7*0
Bifluoride	[FFH]- (g)	-477.1	-477.5	± 3.2	kJ/mol	39.005295 ± 0.000070	18130-74-00
Hydrogen chloride	HCl (aq, 150 H2O)		-165.981	± 0.025	kJ/mol	36.46064 ± 0.00090	7647-01-0*829
Ammonium bromide	(NH4)Br (cr)	-253.72	-270.30	± 0.16	kJ/mol	97.9425 ± 0.0010	12124-97-9*510
(Formyloxy)methyl	HC(O)OCH2 (g, syn)	-148.8	-156.9	± 1.6	kJ/mol	59.0440 ± 0.0017	3122-12-1*1
(Formyloxy)methyl	HC(O)OCH2 (g, anti)	-133.5	-141.7	± 1.9	kJ/mol	59.0440 ± 0.0017	3122-12-1*2
Trinitrogen cation	[N3]+ (g)	1519.4	1516.9	± 1.2	kJ/mol	42.01967 ± 0.00021	12185-03-4*0
Oxalic acid	(COOH)2 (g)	-710.8	-721.4	± 2.1	kJ/mol	90.0349 ± 0.0020	144-62-7*0
Isocyanogen anion	[CNCN]- (g, cis)	386.7	389.6	± 2.9	kJ/mol	52.0354 ± 0.0016	83951-85-32
Diisocyanogen cation	[CNNC]+ (g, cis)	1835.0	1837.7	± 3.5	kJ/mol	52.0343 ± 0.0016	78800-21-22
Methanol anion	[CH3OH]- (g)	54.7	45.6	± 3.1	kJ/mol	32.04241 ± 0.00090	68474-04-4*0
Hydrooxonitrate	[HNO]- (g)	80.0	77.1	± 1.2	kJ/mol	31.01463 ± 0.00032	66057-02-1*0
Cyanoamidogen anion	[HNCN]- (g)	71.5	68.5	± 1.6	kJ/mol	41.03267 ± 0.00082	67131-47-9*0
Cyanamide	H2NCN (g)	140.9	134.7	± 1.5	kJ/mol	42.04006 ± 0.00082	420-04-2*0
Dinitrogen pentoxide	O2NONO2 (cr,l)		-41.14	± 0.42	kJ/mol	108.0105 ± 0.0015	10102-03-1*500
Acetylene anion	[HCCH]- (g, cis)	383.0	383.3	± 3.2	kJ/mol	26.0378 ± 0.0016	50443-89-5*2
Hypobromous acid cation	[HOBr]+ (g)	975.17	964.58	± 0.62	kJ/mol	96.9108 ± 0.0010	154804-02-1*0
Chloroniumyl ion	[HCl]+ (g)	1137.797	1137.731	± 0.0062	kJ/mol	36.46009 ± 0.00090	12258-94-5*0
Hydroxyimidogen anion	[NOH]- (g)	232.7	230.2	± 2.5	kJ/mol	31.01463 ± 0.00032	35337-59-80
Fluorobromomethane	CH2FBr (g)	-198.0	-212.4	± 5.5	kJ/mol	112.9290 ± 0.0013	373-52-4*0
Chlorobromomethane	CH2ClBr (g)	-30.7	-44.7	± 5.5	kJ/mol	129.3833 ± 0.0016	74-97-5*0
Hypofluorous acid cation	[HOF]+ (g)	1142.03	1139.10	± 0.89	kJ/mol	36.00519 ± 0.00031	90243-22-4*0
Nitryl ion	[ONO]+ (g)	961.75	958.19	± 0.20	kJ/mol	46.00499 ± 0.00060	14522-82-8*0
Fluorodibromomethane	CHFBr2 (g)	-159.9	-179.5	± 5.5	kJ/mol	191.8250 ± 0.0022	1868-53-7*0
Bromodichloromethane	CHCl2Br (g)	-39.8	-51.5	± 5.5	kJ/mol	163.8280 ± 0.0022	75-27-4*0
Chlorodibromomethane	CHClBr2 (g)	15.8	-3.0	± 5.5	kJ/mol	208.2793 ± 0.0023	124-48-1*0
Difluorochlorobromomethane	CF2ClBr (g)	-431.4	-442.1	± 5.5	kJ/mol	165.3642 ± 0.0016	353-59-3*0
Dichlorofluorobromomethane	CCl2FBr (g)	-230.2	-239.9	± 5.5	kJ/mol	181.8185 ± 0.0022	353-58-2*0
Dibromofluorochloromethane	CBr2FCl (g)	-170.7	-187.4	± 5.5	kJ/mol	226.2698 ± 0.0023	353-55-9*0
Methyliumylidene	[CH]+ (g)	1619.753	1623.096	± 0.061	kJ/mol	13.01809 ± 0.00080	24361-82-8*0
Difluoromethyliumyl	[CF2]+ (g)	908.48	908.91	± 0.91	kJ/mol	50.00696 ± 0.00080	54250-40-7*0
Methylidyne anion	[CH]- (g)	474.11	477.43	± 0.63	kJ/mol	13.01919 ± 0.00080	28604-54-8*0
Hypofluorous acid anion	[HOF]- (g)	152.8	152.0	± 3.8	kJ/mol	36.00629 ± 0.00031	36505-07-4*0
Formaldehyde anion	[H2CO]- (g)	-24.0	-27.7	± 2.1	kJ/mol	30.02653 ± 0.00087	27837-46-3*0
Ozone cation	[OOO]+ (g)	1352.869	1350.530	± 0.041	kJ/mol	47.99765 ± 0.00090	12596-82-6*0
Hydrogen chloride	HCl (aq, 74 H2O)		-165.548	± 0.027	kJ/mol	36.46064 ± 0.00090	7647-01-0*953
Hypochlorous acid cation	[HOCl]+ (g)	993.8	990.7	± 3.2	kJ/mol	52.45949 ± 0.00095	71606-47-8*0
Trifluorine cation	[F3]+ (g)	1532.5	1530.5	± 2.1	kJ/mol	56.9946610 ± 0.0000015	64710-22-1*0
Dioxygenyl fluoride anion	[FOO]- (g)	-252.0	-252.2	± 3.1	kJ/mol	50.99775 ± 0.00060	23553-17-5*0
Hydrogen chloride	HCl (aq, 140 H2O)		-165.947	± 0.026	kJ/mol	36.46064 ± 0.00090	7647-01-0*907
Difluorophosgene cation	[COF2]+ (g)	653.15	650.52	± 0.61	kJ/mol	66.00636 ± 0.00085	73256-56-1*0
Difluorophosgene anion	[COF2]- (g)	-603.6	-605.5	± 2.9	kJ/mol	66.00745 ± 0.00085	474815-26-4*0
Trioxidanylium	[HOOO]+ (g)	1070.2	1063.9	± 1.3	kJ/mol	49.00559 ± 0.00090	74241-49-9*0
Methylammoniumyl	[CH3NH2]+ (g)	866.9	853.2	± 2.4	kJ/mol	31.05659 ± 0.00088	34516-31-9*0
Dioxaziridinyl cation	[N(OO)]+ (g)	1363.9	1361.3	± 1.7	kJ/mol	46.00499 ± 0.00060	66252-29-70
Methylamine anion	[CH3NH2]- (g)	69.1	54.9	± 4.0	kJ/mol	31.05769 ± 0.00088	81096-79-9*0
Dibromophosgene	COBr2 (l)		-144.46	± 0.95	kJ/mol	187.8181 ± 0.0022	593-95-3*590
2-Chloroethanol	ClCH2CH2OH (l)		-315.11	± 0.54	kJ/mol	80.5132 ± 0.0019	107-07-3*590
2-Bromoethanol	BrCH2CH2OH (l)		-274.98	± 0.47	kJ/mol	124.9645 ± 0.0019	540-51-2*590
Dibromine	Br2 (aq)		-2.16	± 0.20	kJ/mol	159.8080 ± 0.0020	7726-95-6*800
Ethylene anion	[C2H4]- (g, syn)	237.7	231.6	± 2.4	kJ/mol	28.0537 ± 0.0016	34527-91-8*2
Phenylium	[C6H5]+ (g, singlet)	1148.74	1136.84	± 0.95	kJ/mol	77.1034 ± 0.0048	17333-73-2*2
Hydroxyoxoammoniumyl	[HONO]+ (g)	983.6	977.2	± 1.7	kJ/mol	47.01293 ± 0.00061	80371-48-8*0
Imidogen anion	[NH]- (g)	322.63	322.68	± 0.17	kJ/mol	15.015229 ± 0.000099	23841-33-0*0
Fluorobenzene	C6H5F (cr,l)	-152.4	-150.0	± 1.1	kJ/mol	96.1023 ± 0.0048	462-06-6*500
Nitric acid cation	[HNO3]+ (g)	1029.30	1020.23	± 0.70	kJ/mol	63.01233 ± 0.00091	272109-63-4*0
Hydrogen bromide	HBr (aq, 2570 H2O)		-120.70	± 0.15	kJ/mol	80.9119 ± 0.0010	10035-10-6*952
1-Ethylium-1-yl	[CH3CH]+ (g)	1185.7	1178.6	± 2.6	kJ/mol	28.0526 ± 0.0016	85944-79-2*0
Bromobenzene	C6H5Br (cr,l)		60.2	± 1.3	kJ/mol	157.0079 ± 0.0049	108-86-1*500
Acetone	CH3C(O)CH3 (cr,l)	-244.36	-247.48	± 0.37	kJ/mol	58.0791 ± 0.0025	67-64-1*500
2-Propanol	CH3CHOHCH3 (cr,l)	-305.38	-318.18	± 0.36	kJ/mol	60.0950 ± 0.0025	67-63-0*500
Monoammonium succinate	(CH2COOH)2(NH3) (cr)		-1067.95	± 0.72	kJ/mol	135.1186 ± 0.0035	38457-08-8*510
Diammonium succinate	(CH2COOH)2(NH3)2 (cr)		-1182.49	± 0.48	kJ/mol	152.1492 ± 0.0035	2226-88-2*510
1,2-Dichloroethane	(CClH2)2 (cr,l)		-165.26	± 0.59	kJ/mol	98.9586 ± 0.0024	107-06-2*500
Ethylidene anion	[CH3CH]- (g)	328.4	320.9	± 2.1	kJ/mol	28.0537 ± 0.0016	35829-99-3*0
1,1-Dichloroethane	CHCl2CH3 (cr,l)		-158.1	± 1.1	kJ/mol	98.9586 ± 0.0024	75-34-3*500
Chlorine fluoride cation	[ClF]+ (g)	1165.47	1165.66	± 0.64	kJ/mol	54.45055 ± 0.00090	12432-44-9*0
Hydrogen chloride	HCl (aq, 3000 H2O)		-166.743	± 0.024	kJ/mol	36.46064 ± 0.00090	7647-01-0*842
Oxygen difluoride cation	[FOF]+ (g)	1292.24	1289.71	± 0.67	kJ/mol	53.99566 ± 0.00030	39432-25-2*0
Trioxirane	O(OO) (g)	274.5	271.9	± 1.2	kJ/mol	47.99820 ± 0.00090	153851-84-4*0
Dioxofluorine	OFO (g)	522.95	521.21	± 0.90	kJ/mol	50.99720 ± 0.00060	175861-93-5*0
1,2-Propadien-1-ylium-1-yl-3-ylidene	[CCC]+ (g, lin only)	1981.7	1990.4	± 2.2	kJ/mol	36.0316 ± 0.0024	118090-85-0*1
Formic acid	HC(O)OH (cr,l)	-431.65	-424.82	± 0.21	kJ/mol	46.0254 ± 0.0010	64-18-6*500
1-Methylethenylium	[CH3CCH2]+ (g)	996.3	986.8	± 2.5	kJ/mol	41.0713 ± 0.0024	50457-57-3*0
1-Methylethenyl anion	[CH3CCH2]- (g)	199.4	188.3	± 2.8	kJ/mol	41.0723 ± 0.0024	65887-19-6*0
Oxadiazirine	[O(NN)]+ (g)	1512.8	1510.3	± 2.8	kJ/mol	44.01233 ± 0.00033	227934-45-40
Trioxygen difluoride	FOOOF (g)	116.8	111.4	± 7.8	kJ/mol	85.99501 ± 0.00090	16829-28-0*0
Water anion	[H2O]- (g, ?)	-74.2	-77.1	± 4.3	kJ/mol	18.01583 ± 0.00033	12259-30-2*0
Ethylidyne anion	[CH3C]- (g)	458.2	453.9	± 2.8	kJ/mol	27.0458 ± 0.0016	117768-70-4*0
2-Propen-3-ylium-1-ylidyne	[CHCHC]+ (g)	1791.1	1792.7	± 2.6	kJ/mol	38.0474 ± 0.0024	161054-36-0*0
Xenon cation	Xe+ (g)	1170.354	1170.354	± 0.0062	kJ/mol	131.2895 ± 0.0200	24203-25-6*0
Propenediylidene anion	[CHCHC]- (g)	588.7	589.9	± 2.3	kJ/mol	38.0485 ± 0.0024	161054-36-00
Dihydrogen	H2 (g, ortho)	1.417	0.019	± 0.000	kJ/mol	2.01588 ± 0.00014	1333-74-0*1
Hydraziniumyl	[H2NNH2]+ (g)	887.4	873.7	± 2.5	kJ/mol	32.04469 ± 0.00031	20771-51-1*0
Bromoniumyl	[HBr]+ (g)	1097.71	1089.86	± 0.15	kJ/mol	80.9114 ± 0.0010	12258-64-9*0
Hydroxylamine	NH2OH (aq, undissoc)		-97.1	± 2.2	kJ/mol	33.02996 ± 0.00037	7803-49-8*1000
Nitric acid	HNO3 (aq, 3 H2O)		-197.73	± 0.19	kJ/mol	63.01288 ± 0.00091	7697-37-2*805
Nitric acid monohydrate	HNO3(H2O) (cr,l)	-479.14	-472.64	± 0.19	kJ/mol	81.0282 ± 0.0012	13444-82-1*500
Deuterium hydride	HD (g)	0.328	0.319	± 0.000	kJ/mol	3.022042 ± 0.000070	13983-20-5*0
1-Ethylium-1-ylidene	[CH3C]+ (g)	1328.8	1325.8	± 2.8	kJ/mol	27.0447 ± 0.0016	78949-84-5*0
Dioxiranylidene cation	[C(OO)]+ (g)	1409.3	1411.7	± 6.0	kJ/mol	44.0090 ± 0.0010	138832-57-20
Acetic acid	CH3C(O)OH (g, anti)	-397.6	-411.4	± 1.2	kJ/mol	60.0520 ± 0.0017	64-19-7*2
Peroxyimidogen cation	[NOO]+ (g)	1408.3	1405.5	± 2.8	kJ/mol	46.00499 ± 0.00060	60488-32-60
Acetic acid	CH3C(O)OH (aq, 1000 H2O)		-484.90	± 0.23	kJ/mol	60.0520 ± 0.0017	64-19-7*839
1,5-Hexadiene	CH2CHCH2CH2CHCH2 (cr,l)		54.42	± 0.32	kJ/mol	82.1436 ± 0.0049	592-42-7*500
Methyl formate	HC(O)OCH3 (l)		-386.13	± 0.58	kJ/mol	60.0520 ± 0.0017	107-31-3*500
Ethylene glycol	(CH2OH)2 (cr,l)	-448.68	-455.20	± 0.38	kJ/mol	62.0678 ± 0.0018	107-21-1*500
Methane anion	[CH4]- (g)	10.4	3.1	± 4.1	kJ/mol	16.04301 ± 0.00085	27680-53-1*0
Deuterium hydride cation	[HD]+ (g)	1490.498	1490.587	± 0.000	kJ/mol	3.021493 ± 0.000070	12181-16-7*0
Oxalic acid	(COOH)2 (cr)		-819.28	± 0.46	kJ/mol	90.0349 ± 0.0020	144-62-7*500
Iodine monochloride	ICl (cr)	-36.511	-35.537	± 0.063	kJ/mol	162.35717 ± 0.00090	7790-99-0*510
Dimethylamine	(CH3)2NH (l)		-41.10	± 0.73	kJ/mol	45.0837 ± 0.0017	124-40-3*500
Trimethylamine	(CH3)3N (l)		-45.74	± 0.62	kJ/mol	59.1103 ± 0.0025	75-50-3*500
Cyanogen cation	[NCCN]+ (g)	1598.28	1600.50	± 0.44	kJ/mol	52.0343 ± 0.0016	37354-81-7*0
Cyanogen anion	[NCCN]- (g)	281.4	284.5	± 2.7	kJ/mol	52.0354 ± 0.0016	11118-88-0*0
Isocyanogen cation	[CNCN]+ (g)	1652.8	1654.2	± 1.7	kJ/mol	52.0343 ± 0.0016	133415-63-1*0
Azide ion	[N3]- (aq)		272.76	± 0.53	kJ/mol	42.02077 ± 0.00021	14343-69-2*800
Dioxiranylidene anion	[C(OO)]- (g, open)	-111.6	-111.1	± 3.5	kJ/mol	44.0100 ± 0.0010	138832-58-30
Nitric acid	HNO3 (aq, 1 H2O)		-186.81	± 0.19	kJ/mol	63.01288 ± 0.00091	7697-37-2*801
Cyclopropyl anion	[CH(CH2CH2)]- (g)	262.7	249.9	± 4.7	kJ/mol	41.0723 ± 0.0024	1724-45-4*0
Diisocyanogen anion	[CNNC]- (g)	456.7	463.6	± 5.7	kJ/mol	52.0354 ± 0.0016	78800-22-30
Diazoethenylidene cation	[NNCC]+ (g)	1777.0	1779.1	± 6.1	kJ/mol	52.0343 ± 0.0016	130760-10-00
Diazoethenylidene anion	[NNCC]- (g)	536.0	538.5	± 5.8	kJ/mol	52.0354 ± 0.0016	130760-11-10
3H-diazirin-3-ylidene-methylene	CC(NN) (g)	833.6	836.1	± 3.6	kJ/mol	52.0349 ± 0.0016	204253-88-3*0
Isocyanomethyliumylidene	[CNC]+ (g)	1612.5	1618.1	± 6.2	kJ/mol	38.0276 ± 0.0016	78271-45-1*0
Isocyanomethylidyne anion	[CNC]- (g)	478.6	482.3	± 5.9	kJ/mol	38.0287 ± 0.0016	53590-27-50
Nitrogen sesquioxide cation	[ONNO2]+ (g)	1031.0	1027.6	± 4.1	kJ/mol	76.01113 ± 0.00091	10544-73-70
Cyanomethyliumylidene	[CCN]+ (g)	1711.0	1716.5	± 6.0	kJ/mol	38.0276 ± 0.0016	76619-90-4*0
Cyanomethylidyne anion	[CCN]- (g)	406.6	410.3	± 5.7	kJ/mol	38.0287 ± 0.0016	12373-35-2*0
2,3-didehydro-1H-azirin-1-yl	N(CC) (g)	722.1	726.2	± 4.9	kJ/mol	38.0281 ± 0.0016	439586-06-8*0
Cyanoaminyliumyl	[NCN]+ (g)	1676.3	1677.6	± 3.0	kJ/mol	40.02363 ± 0.00081	316122-03-9*0
Cyanoamidogen anion	[NCN]- (g)	216.3	216.4	± 1.4	kJ/mol	40.02473 ± 0.00081	189879-95-6*0
Methanol	CH3OH (l)	-235.08	-238.42	± 0.17	kJ/mol	32.04186 ± 0.00090	67-56-1*500
Cyanamide	H2NCN (cr)		58.91	± 0.54	kJ/mol	42.04006 ± 0.00082	420-04-2*500
Diazomethyliumyl	[CNN]+ (g)	1643.4	1645.2	± 3.7	kJ/mol	40.02363 ± 0.00081	307495-90-5*0
Diazomethylene anion	[CNN]- (g)	409.9	410.1	± 2.5	kJ/mol	40.02473 ± 0.00081	205498-92-6*0
3H-Diazirin-3-ylidene	C(NN) (g)	581.6	581.9	± 3.0	kJ/mol	40.02418 ± 0.00081	253308-70-2*0
Trioxidanyl	HOOO (g)	25.32	23.23	± 0.13	kJ/mol	49.00614 ± 0.00090	12500-78-6*0
Hydrogen chloride	HCl (aq, 200 H2O)		-166.106	± 0.024	kJ/mol	36.46064 ± 0.00090	7647-01-0*830
Hydrazine anion	[H2NNH2]- (g)	211.0	197.1	± 3.7	kJ/mol	32.04579 ± 0.00031	65391-88-0*0
Bromosyl bromide	BrBrO (g)	180.5	164.7	± 2.3	kJ/mol	175.8074 ± 0.0020	68322-97-4*0
Oxygen difluoride anion	[FOF]- (g)	-194.0	-194.4	± 3.8	kJ/mol	53.99675 ± 0.00030	7783-41-70
Trifluorine	F3 (g)	83.6	84.3	± 2.4	kJ/mol	56.9952096 ± 0.0000015	73455-86-4*0
Methylene chloride	CH2Cl2 (l)		-123.28	± 0.61	kJ/mol	84.9320 ± 0.0020	75-09-2*590
Hydrogen chloride	HCl (aq, 1000 H2O)		-166.567	± 0.024	kJ/mol	36.46064 ± 0.00090	7647-01-0*839
Hydrogen bromide	HBr (aq, 1000 H2O)		-120.57	± 0.15	kJ/mol	80.9119 ± 0.0010	10035-10-6*839
Hydrazide	[N2H3]- (g)	252.9	243.0	± 2.5	kJ/mol	31.03785 ± 0.00025	25415-88-7*0
1-Propynylium	[CH3CC]+ (g)	1545.8	1543.9	± 2.6	kJ/mol	39.0554 ± 0.0024	24858-94-4*0
Dioxygen difluoride anion	[FOOF]- (g)	-235.6	-235.8	± 5.6	kJ/mol	69.99615 ± 0.00060	7783-45-10
Fluorosyl fluoride cation	[FFO]+ (g)	1409.3	1409.7	± 6.3	kJ/mol	53.99566 ± 0.00030	86825-50-50
Dioxymethylidyne cation	[COO]+ (g, doublet)	1434.5	1437.8	± 3.7	kJ/mol	44.0090 ± 0.0010	791121-04-52
Fluorosyl fluoride anion	[FFO]- (g)	-53.5	-52.9	± 6.1	kJ/mol	53.99675 ± 0.00030	86825-57-20
Deuterium atom cation	D+ (g)	1532.211	1534.123	± 0.000	kJ/mol	2.01355319809 ± 0.00000000040	14464-47-2*0
1-Ethenylium-1-yl	[CCH2]+ (g)	1508.6	1509.0	± 2.7	kJ/mol	26.0367 ± 0.0016	80541-07-7*0
Difluoromethylene anion	[CF2]- (g)	-211.12	-209.89	± 0.62	kJ/mol	50.00805 ± 0.00080	66212-40-6*0
Ammonia anion	[NH3]- (g)	38.3	31.4	± 2.8	kJ/mol	17.03111 ± 0.00022	76211-32-00
Dihydrogen cation	[H2]+ (g, ortho)	1489.060	1488.480	± 0.000	kJ/mol	2.01533 ± 0.00014	12184-90-6*1
Fluoromethylidyne anion	[CF]- (g)	200.6	204.1	± 2.1	kJ/mol	31.00965 ± 0.00080	33412-12-3*0
Hydrochlorate ion	[HCl]- (g)	-25.5	-24.5	± 3.0	kJ/mol	36.46119 ± 0.00090	63099-75-2*0
Formaldehyde	H2CO (cr, paraformaldehyde)		-179.2	± 1.6	kJ/mol	30.02598 ± 0.00087	50-00-0*500
Hydrogen peroxide	H2O2 (cr,l)	-193.158	-187.341	± 0.080	kJ/mol	34.01468 ± 0.00062	7722-84-1*500
Hydrazoic acid cation	[HNNN]+ (g)	1333.94	1328.26	± 0.89	kJ/mol	43.02761 ± 0.00022	58852-14-5*0
Hydronium radical	(H2O)(H) (g, vdW?)	-19.0	-22.1	± 2.3	kJ/mol	19.02322 ± 0.00037	12168-76-2*100
NON cation	[NON]+ (g)	1444.1	1444.3	± 2.7	kJ/mol	44.01233 ± 0.00033	227934-46-50
Ethane anion	[C2H6]- (g)	8.4	-7.0	± 3.2	kJ/mol	30.0696 ± 0.0017	54064-82-3*0
1,2-Difluoroacetylene cation	[FCCF]+ (g)	1080.0	1083.0	± 1.8	kJ/mol	62.0177 ± 0.0016	268566-70-7*0
Dioxymethylidyne cation	[(C)(OO)]+ (g, vdW quartet)	1384.7	1389.0	± 5.5	kJ/mol	44.0090 ± 0.0010	791121-04-5101
Cycloprop-1-enylium	[CH2(CHC)]+ (g)	1502.6	1498.4	± 2.2	kJ/mol	39.0554 ± 0.0024	117067-78-4*0
Carbon dioxide cation	[CO2]+ (g, quartet)	1327.1	1328.0	± 3.2	kJ/mol	44.0090 ± 0.0010	12181-61-2*1
Hydrazoic acid anion	[HNNN]- (g)	317.4	311.0	± 2.5	kJ/mol	43.02871 ± 0.00022	203264-98-6*0
Ethanide	[CH3CH2]- (g)	155.2	143.5	± 1.9	kJ/mol	29.0616 ± 0.0016	25013-41-6*0
Hydrogen fluoride	HF (aq, 400 H2O)		-321.49	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*832
Cycloprop-1-enyl anion	[CH2(CHC)]- (g)	373.8	369.3	± 2.2	kJ/mol	39.0565 ± 0.0024	80251-77-0*0
Propane cation	[CH3CH2CH3]+ (g)	975.0	955.1	± 1.6	kJ/mol	44.0951 ± 0.0025	34479-70-4*0
Cycloprop-2-enyl anion	[CH(CHCH)]- (g)	515.3	512.2	± 2.2	kJ/mol	39.0565 ± 0.0024	20829-57-6*0
Dioxygen	O2 (g, singlet)	94.410	94.383	± 0.000	kJ/mol	31.99880 ± 0.00060	7782-44-7*2
2-Iodoethanol	ICH2CH2OH (l)		-207.2	± 2.4	kJ/mol	171.9650 ± 0.0017	624-76-0*590
1,3-Butadiyne cation	[HCCCCH]+ (g)	1440.65	1441.51	± 0.89	kJ/mol	50.0581 ± 0.0032	55468-55-8*0
Tricarbon dioxide cation	[OCCCO]+ (g)	927.0	930.5	± 1.3	kJ/mol	68.0304 ± 0.0025	151528-67-5*0
Tricarbon dioxide anion	[OCCCO]- (g)	-133.5	-129.8	± 2.5	kJ/mol	68.0314 ± 0.0025	109362-94-9*0
Methylamine	CH3NH2 (l)		-44.68	± 0.58	kJ/mol	31.05714 ± 0.00088	74-89-5*500
Carbon dioxide cation	[CO2]+ (g)	936.102	936.937	± 0.023	kJ/mol	44.0090 ± 0.0010	12181-61-2*0
Benzene anion	[C6H6]- (g)	211.7	199.3	± 3.7	kJ/mol	78.1124 ± 0.0048	34562-85-1*0
NON anion	[NON]- (g)	498.1	495.6	± 2.7	kJ/mol	44.01343 ± 0.00033	227934-47-60
Cyclopropenylidene anion	[C(CHCH)]- (g)	544.3	543.8	± 2.2	kJ/mol	38.0485 ± 0.0024	16165-40-50
Peroxynitrous acid	HOONO (g)	-6.14	-12.77	± 0.37	kJ/mol	63.01288 ± 0.00091	14691-52-2*0
Nitric acid trihydrate	HNO3(H2O)3 (cr,l)	-1062.05	-1055.20	± 0.21	kJ/mol	117.0587 ± 0.0019	13444-83-2*500
Carbon monoxide anion	[CO]- (g)	34.3	38.0	± 2.2	kJ/mol	28.01065 ± 0.00085	12539-63-8*0
o-Benzyne cation	[C6H4]+ (g)	1398.9	1391.4	± 3.0	kJ/mol	76.0954 ± 0.0048	70220-84-7*0
Chlorosyl ion	[ClO]+ (g)	1150.58	1150.42	± 0.79	kJ/mol	51.45155 ± 0.00095	12301-79-0*0
Toluene	C6H5CH3 (g)	73.69	50.41	± 0.37	kJ/mol	92.1384 ± 0.0056	108-88-3*0
Toluene	C6H5CH3 (l)	20.11	12.36	± 0.36	kJ/mol	92.1384 ± 0.0056	108-88-3*500
Hydrogen fluoride	HF (aq, 18.5 H2O)		-321.06	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*887
Hydrofluorate ion	[HF]- (g)	-75.4	-74.9	± 2.0	kJ/mol	20.006892 ± 0.000070	37249-79-9*0
Iodine atom	I (g, 2P3/2 only)	107.157	106.757	± 0.0021	kJ/mol	126.904470 ± 0.000030	14362-44-8*1
Dicarbon monoxide	CCO (g)	375.0	379.0	± 1.2	kJ/mol	40.0208 ± 0.0016	12071-23-7*0
Carbon dioxide anion	[CO2]- (g)	-340.2	-339.7	± 2.4	kJ/mol	44.0100 ± 0.0010	14485-07-5*0
Iodobenzene cation	[C6H5I]+ (g)	1022.9	1007.4	± 1.1	kJ/mol	204.0078 ± 0.0048	38406-85-8*0
Nitrato	[NO3]+ (g)	1290.52	1285.80	± 0.86	kJ/mol	62.00439 ± 0.00090	133057-96-2*0
Nitrosobenzene	C6H5NO (g)	215.6	198.6	± 1.5	kJ/mol	107.1100 ± 0.0048	586-96-9*0
n-Hexane	C6H14 (l)	-180.01	-198.67	± 0.42	kJ/mol	86.1754 ± 0.0049	110-54-3*500
2-Butyne	(CH3)CC(CH3) (g)	158.73	145.77	± 0.78	kJ/mol	54.0904 ± 0.0032	503-17-3*0
1-Butene	CH2CHCH2CH3 (g)	20.95	-0.01	± 0.46	kJ/mol	56.1063 ± 0.0032	106-98-9*0
cis-2-Butene	CH3CHCHCH3 (g)	13.97	-7.30	± 0.51	kJ/mol	56.1063 ± 0.0032	590-18-1*0
trans-2-Butene	CH3CHCHCH3 (g)	9.41	-11.15	± 0.49	kJ/mol	56.1063 ± 0.0032	624-64-6*0
Isobutene	CH2C(CH3)2 (g)	3.54	-17.52	± 0.51	kJ/mol	56.1063 ± 0.0032	115-11-7*0
Heptane	C7H16 (l)	-201.46	-223.91	± 0.74	kJ/mol	100.2019 ± 0.0057	142-82-5*500
Octane	C8H18 (l)	-226.61	-249.73	± 0.79	kJ/mol	114.2285 ± 0.0065	111-65-9*500
2,2,4-Trimethylpentane	(CH3)2CHCH2C(CH3)3 (l)	-224.4	-258.9	± 1.5	kJ/mol	114.2285 ± 0.0065	540-84-1*500
Trifluoroethylene	C2HF3 (g)	-482.8	-487.8	± 8.4	kJ/mol	82.0245 ± 0.0016	359-11-5*0
Norbornadiene	(CHCH)CHCH2CH(CHCH) (g)	237.9	212.5	± 1.2	kJ/mol	92.1384 ± 0.0056	121-46-0*0
Norbornadiene	(CHCH)CHCH2CH(CHCH) (l)		179.1	± 1.1	kJ/mol	92.1384 ± 0.0056	121-46-0*500
2,3-Butanedione	(CH3CO)2 (cr,l)		-365.48	± 0.55	kJ/mol	86.0892 ± 0.0033	431-03-8*500
2,3-Butanedione	(CH3CO)2 (g)	-310.00	-326.57	± 0.79	kJ/mol	86.0892 ± 0.0033	431-03-8*0
Succinic acid	(CH2COOH)2 (cr,l)	-918.54	-940.26	± 0.13	kJ/mol	118.0880 ± 0.0034	110-15-6*500
Ethynylene cation	[C2]+ (g)	1967.8	1974.4	± 1.9	kJ/mol	24.0209 ± 0.0016	12595-79-8*0
1,2-Difluoroethane	(CFH2)2 (g)	-437.0	-450.4	± 5.0	kJ/mol	66.0500 ± 0.0016	624-72-6*0
Carbide	[C2]- (g)	504.88	511.46	± 0.53	kJ/mol	24.0219 ± 0.0016	12595-78-7*0
1,2-Diiodoethane	(CIH2)2 (g)	87.80	73.13	± 0.90	kJ/mol	281.8621 ± 0.0016	624-73-7*0
1,2-Diiodoethane	(CIH2)2 (cr,l)		9.27	± 0.60	kJ/mol	281.8621 ± 0.0016	624-73-7*500
Hydrazine	H2NNH2 (cr,l)	57.38	50.82	± 0.19	kJ/mol	32.04524 ± 0.00031	302-01-2*500
1,1-Dibromoethane	CHBr2CH3 (g)	-9.3	-36.3	± 7.8	kJ/mol	187.8612 ± 0.0026	557-91-5*0
Xenon hydride cation	[XeH]+ (g)	1038.38	1036.60	± 0.93	kJ/mol	132.2974 ± 0.0200	37276-91-8*0
Methyl bromide	CH3Br (l)	-56.73	-59.74	± 0.19	kJ/mol	94.9385 ± 0.0013	74-83-9*590
Bromodioxy	BrOO (g)	119.3	110.2	± 4.0	kJ/mol	111.9028 ± 0.0012	67177-47-3*0
Hydrazine monohydrate	(H2NNH2)(H2O) (l)		-242.52	± 0.19	kJ/mol	50.06052 ± 0.00053	7803-57-8*500
Oxoniumyl ion	[H2O]+ (g, ortho)	978.475	975.571	± 0.029	kJ/mol	18.01473 ± 0.00033	56583-62-1*1
Deuteride	D- (g)	146.991	148.904	± 0.0021	kJ/mol	2.01465035791 ± 0.00000000040	14452-69-8*0
Cyclopropane cation	[CH2(CH2CH2)]+ (g)	1021.8	1006.4	± 1.6	kJ/mol	42.0792 ± 0.0024	34496-93-0*0
Tetraazatetrahedrane	N4 (g)	763.9	757.4	± 1.7	kJ/mol	56.02696 ± 0.00028	12596-63-3*0
Acetic acid	CH3C(O)OH (aq, 500 H2O)		-484.88	± 0.23	kJ/mol	60.0520 ± 0.0017	64-19-7*833
Acetic acid	CH3C(O)OH (aq, 10000 H2O)		-484.93	± 0.23	kJ/mol	60.0520 ± 0.0017	64-19-7*850
Acetaldehyde	CH3CHO (cr,l)	-186.99	-191.70	± 0.36	kJ/mol	44.0526 ± 0.0017	75-07-0*500
Hydrogen fluoride	HF (aq, 45 H2O)		-321.17	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*906
Diatomic bromine cation	[Br2]+ (g)	1060.33	1045.38	± 0.23	kJ/mol	159.8075 ± 0.0020	12595-71-0*0
Dihydrogen	H2 (g, para)	0.000	-0.058	± 0.000	kJ/mol	2.01588 ± 0.00014	1333-74-0*2
n-Hexane	C6H14 (g)	-130.25	-167.12	± 0.42	kJ/mol	86.1754 ± 0.0049	110-54-3*0
Chlorine atom	Cl (g, 2P3/2 only)	119.621	121.228	± 0.0021	kJ/mol	35.45270 ± 0.00090	22537-15-1*1
Methyl formate	HC(O)OCH3 (g)	-344.74	-357.79	± 0.58	kJ/mol	60.0520 ± 0.0017	107-31-3*0
Formaldehyde	H2CO (cr, polyoxymethylene)		-170.88	± 0.21	kJ/mol	30.02598 ± 0.00087	50-00-0*501
Water trimer	(H2O)3 (g)	-762.75	-776.85	± 0.21	kJ/mol	54.04584 ± 0.00099	31014-12-7*0
Formaldehyde	H2CO (aq)		-171.13	± 0.59	kJ/mol	30.02598 ± 0.00087	50-00-0*800
Ethyl bromide	CH3CH2Br (l)	-55.59	-91.12	± 0.28	kJ/mol	108.9651 ± 0.0019	74-96-4*500
Dihydrogen cation	[H2]+ (g, para)	1488.364	1488.480	± 0.000	kJ/mol	2.01533 ± 0.00014	12184-90-6*2
Propylene cation	[CH3CHCH2]+ (g)	975.36	962.40	± 0.40	kJ/mol	42.0792 ± 0.0024	34504-10-4*0
Vinyl iodide	CH2CHI (g)	139.4	130.6	± 1.2	kJ/mol	153.9497 ± 0.0016	593-66-8*0
1-Hydroxyethyl	CH3CHOH (g)	-42.07	-55.50	± 0.62	kJ/mol	45.0605 ± 0.0017	2348-46-1*0
Hydrazoic acid	HNNN (aq, undissoc)		257.79	± 0.54	kJ/mol	43.02816 ± 0.00022	7782-79-8*1000
Tribromide ion	[Br3]- (aq)		-129.54	± 0.25	kJ/mol	239.7125 ± 0.0030	14522-80-6*800
Deuterium molecule cation	[D2]+ (g)	1492.286	1492.361	± 0.000	kJ/mol	4.02765497609 ± 0.00000000080	12184-84-8*0
Iodine monochloride	ICl (l)		-24.048	± 0.063	kJ/mol	162.35717 ± 0.00090	7790-99-0*590
Dihydrogen anion	[H2]- (g)	253.8	254.7	± 1.2	kJ/mol	2.01643 ± 0.00014	12184-89-3*0
1,2-Propadien-1-yl-3-ylidene anion	[CCC]- (g)	622.6	630.0	± 1.4	kJ/mol	36.0326 ± 0.0024	109292-47-9*0
Hydrogen peroxide cation	[H2O2]+ (g, trans, ortho)	896.85	889.87	± 0.57	kJ/mol	34.01413 ± 0.00062	12325-10-9*11
Water	H2O (g, para)	-238.928	-241.831	± 0.026	kJ/mol	18.01528 ± 0.00033	7732-18-5*2
Tetrazete	N4 (g)	769.6	763.6	± 2.4	kJ/mol	56.02696 ± 0.00028	42851-09-2*0
Hydrogen iodide	HI (aq)		-56.826	± 0.090	kJ/mol	127.912410 ± 0.000076	10034-85-2*800
Water	H2O (cr)	-286.298	-292.738	± 0.026	kJ/mol	18.01528 ± 0.00033	7732-18-5*510
Hydroxymethylene	HCOH (g)	111.98	108.22	± 0.41	kJ/mol	30.02598 ± 0.00087	19710-56-6*0
Hydrazoic acid	HNNN (aq)		272.76	± 0.53	kJ/mol	43.02816 ± 0.00022	7782-79-8*800
Hydroxylamine	NH2OH (cr,l)		-107.51	± 0.65	kJ/mol	33.02996 ± 0.00037	7803-49-8*500
Tricarbon dioxide	OCCCO (cr,l)	-133.0	-117.9	± 1.2	kJ/mol	68.0309 ± 0.0025	504-64-3*500
Difluorine cation	[F2]+ (g)	1514.301	1514.475	± 0.013	kJ/mol	37.9962578 ± 0.0000010	12184-86-0*0
Trioxirane cation	[O(OO)]+ (g)	1444.4	1442.3	± 2.3	kJ/mol	47.99765 ± 0.00090	153851-84-40
Hydroxylamine	NH2OH (g)	-33.13	-43.49	± 0.49	kJ/mol	33.02996 ± 0.00037	7803-49-8*0
Oxygen fluoride	OOF2 (g)	75.6	71.3	± 7.8	kJ/mol	69.99561 ± 0.00060	183051-89-0*0
Carbon monoxide	CO (g, singlet only)	-113.802	-110.522	± 0.026	kJ/mol	28.01010 ± 0.00085	630-08-0*2
Fluorine atom	F (g, 2P3/2 only)	77.288	79.072	± 0.055	kJ/mol	18.99840320 ± 0.00000050	14762-94-8*1
Oxonium	[H3O]+ (g, para)	605.55	598.80	± 0.56	kJ/mol	19.02267 ± 0.00037	13968-08-6*2
1,2-Propadien-1-ylium-1-yl-3-ylidene	[CCC]+ (g)	1954.9	1962.0	± 2.3	kJ/mol	36.0316 ± 0.0024	118090-85-0*0
Iodine atom	I (g, 2P1/2 only)	198.109	197.709	± 0.0021	kJ/mol	126.904470 ± 0.000030	14362-44-8*2
Ammonium hydroxide	NH4OH (aq, undissoc)		-366.719	± 0.062	kJ/mol	35.04584 ± 0.00047	1336-21-6*1000
1-Butyne	CH3CH2CCH (g)	178.97	165.39	± 0.85	kJ/mol	54.0904 ± 0.0032	107-00-6*0
Cyclobutene	C4H6 (g)	173.9	156.9	± 1.6	kJ/mol	54.0904 ± 0.0032	822-35-5*0
Carbon atom	C (g, triplet only)	711.395	716.880	± 0.055	kJ/mol	12.01070 ± 0.00080	7440-44-0*1
2-Propanol	CH3CHOHCH3 (g)	-248.73	-272.83	± 0.36	kJ/mol	60.0950 ± 0.0025	67-63-0*0
Trihydrogen cation	[H3]+ (g, para)	1110.304	1106.697	± 0.013	kJ/mol	3.02327 ± 0.00021	28132-48-1*2
(Z)-1,2-Diiodoethene	C2H2I2 (g)	215.75	207.46	± 0.45	kJ/mol	279.8462 ± 0.0016	590-26-1*0
(E)-1,2-Diiodoethene	C2H2I2 (g)	214.86	207.46	± 0.45	kJ/mol	279.8462 ± 0.0016	590-27-2*0
1,3-Cyclopentadiene	C5H6 (g)	118.3	101.3	± 2.5	kJ/mol	66.1011 ± 0.0040	542-92-7*0
Hydrogen peroxide cation	[H2O2]+ (g, cis, para)	930.90	924.04	± 0.94	kJ/mol	34.01413 ± 0.00062	12325-10-9*22
Hydrogen peroxide	H2O2 (g, para)	-129.468	-135.453	± 0.063	kJ/mol	34.01468 ± 0.00062	7722-84-1*2
Tetrabromomethane	CBr4 (cr, monoclinic)		47.8	± 1.3	kJ/mol	331.6267 ± 0.0041	558-13-4*500
Bromine atom	Br (g, 2P3/2 only)	117.914	111.852	± 0.056	kJ/mol	79.9040 ± 0.0010	10097-32-2*1
Tetraiodomethane	CI4 (cr, monoclinic)		392.5	± 8.0	kJ/mol	519.62858 ± 0.00081	507-25-5*500
1,2-Dibromoethane	(CBrH2)2 (cr,l)		-79.3	± 1.3	kJ/mol	187.8612 ± 0.0026	106-93-4*500
Krypton hydride cation	[KrH]+ (g)	1106.49	1104.71	± 0.70	kJ/mol	84.8074 ± 0.1000	37276-90-7*0
Fluorine atom	F (g, 2P1/2 only)	82.122	83.907	± 0.055	kJ/mol	18.99840320 ± 0.00000050	14762-94-8*2
Cyclopropylium	[CH(CH2CH2)]+ (g)	1103.3	1091.8	± 6.0	kJ/mol	41.0713 ± 0.0024	1724-43-2*0
Water	H2O (cr, l, eq.press.)	-286.299	-285.827	± 0.026	kJ/mol	18.01528 ± 0.00033	7732-18-5*499
2-Hydroxyethylium	[CH2CH2OH]+ (g)	1019.6	1007.5	± 1.6	kJ/mol	45.0600 ± 0.0017	38607-31-7*0
Hydrazoic acid	HNNN (cr,l)		261.70	± 0.71	kJ/mol	43.02816 ± 0.00022	7782-79-8*500
Cyanogen chloride cation	[ClCN]+ (g)	1325.83	1327.15	± 0.96	kJ/mol	61.4696 ± 0.0012	37612-72-9*0
Formic acid cation	[HC(O)OH]+ (g, syn-anti equilib)	721.78	715.21	± 0.28	kJ/mol	46.0248 ± 0.0010	50614-05-6*0
Diamond	C (diamond)	2.391	1.863	± 0.044	kJ/mol	12.01070 ± 0.00080	7440-44-0*501
Isocyanogen bromide	BrNC (g)	344.2	338.6	± 3.7	kJ/mol	105.9214 ± 0.0013	65997-98-0*0
Propargylenide	[HCCCH]- (g)	436.54	439.74	± 0.98	kJ/mol	38.0485 ± 0.0024	82906-05-6*0
Formic acid anion	[HC(O)OH]- (g, syn-anti equilib)	-254.5	-260.7	± 2.2	kJ/mol	46.0259 ± 0.0010	19066-82-1*0
Trioxidanyl	HOOO (g, cis)	26.29	23.01	± 0.19	kJ/mol	49.00614 ± 0.00090	12500-78-6*2
Isocyanogen chloride	ClNC (g)	314.8	316.6	± 2.5	kJ/mol	61.4701 ± 0.0012	75754-69-7*0
Acetylene anion	[HCCH]- (g)	359.5	359.3	± 3.0	kJ/mol	26.0378 ± 0.0016	50443-89-5*0
Fluoro(fluorooxy)methylene	FCOF (g)	-135.8	-137.0	± 2.0	kJ/mol	66.00691 ± 0.00085	479587-30-9*0
2-Cyclopropyn-1-ylidene	C(CC) (g)	905.6	912.5	± 2.0	kJ/mol	36.0321 ± 0.0024	102508-15-6*0
Oxonium	[H3O]+ (g, ortho)	605.61	598.80	± 0.56	kJ/mol	19.02267 ± 0.00037	13968-08-6*1
cis-Dinitrogen dioxide	ONNO (g, cis)	172.83	171.06	± 0.14	kJ/mol	60.01228 ± 0.00062	57932-56-6*0
Nitrogen atom anion	N- (g)	489.2	491.5	± 4.2	kJ/mol	14.007289 ± 0.000070	17778-87-9*0
Iodosyl ion	[IO]+ (g)	1066.1	1064.1	± 2.0	kJ/mol	142.90332 ± 0.00030	81182-81-2*0
Diazene anion	[HNNH]- (g, trans-cis-iso equilib)	269.3	262.5	± 1.7	kJ/mol	30.02991 ± 0.00020	100429-75-2*0
Hydroxyformyl	HOCO (g, trans-cis equilib)	-180.95	-183.53	± 0.48	kJ/mol	45.0174 ± 0.0010	2564-86-5*0
Phosgene	COCl2 (cr, l, I+liquid)		-242.61	± 0.28	kJ/mol	98.9155 ± 0.0020	75-44-5*501
Phosgene	COCl2 (cr, l, II+liquid)	-255.31	-242.61	± 0.28	kJ/mol	98.9155 ± 0.0020	75-44-5*502
Bromine atom	Br (g, 2P1/2 only)	161.998	155.936	± 0.056	kJ/mol	79.9040 ± 0.0010	10097-32-2*2
Hydroxyformyl anion	[HOCO]- (g, trans-cis equilib)	-319.35	-321.42	± 0.58	kJ/mol	45.0180 ± 0.0010	78944-70-4*0
Chlorine atom	Cl (g, 2P1/2 only)	130.177	131.783	± 0.0021	kJ/mol	35.45270 ± 0.00090	22537-15-1*2
Bromoform	CBr3H (l)		1.5	± 1.3	kJ/mol	252.7306 ± 0.0031	75-25-2*590
Diazene anion	[HNNH]- (g, trans-cis equilib)	269.3	262.5	± 1.7	kJ/mol	30.02991 ± 0.00020	100429-75-2*1
Hydroxymethylene cation	[HCOH]+ (g)	972.2	968.6	± 1.6	kJ/mol	30.02543 ± 0.00087	135395-06-1*0
Propynylidene	HCCCH (g)	543.08	546.08	± 0.67	kJ/mol	38.0480 ± 0.0024	67152-18-5*0
Cyanogen	NCCN (cr,l)	273.93	289.18	± 0.43	kJ/mol	52.0349 ± 0.0016	460-19-5*500
2-Iodoethanol	ICH2CH2OH (g)	-132.0	-150.2	± 2.5	kJ/mol	171.9650 ± 0.0017	624-76-0*0
Oxonium	[H3O]+ (aq)		-285.825	± 0.026	kJ/mol	19.02267 ± 0.00037	13968-08-6*800
Methylene	CH2 (g)	390.96	391.52	± 0.14	kJ/mol	14.02658 ± 0.00081	2465-56-7*0
Hydroxymethylene anion	[HCOH]- (g)	148.2	145.4	± 1.8	kJ/mol	30.02653 ± 0.00087	207914-87-2*0
Dinitrogen tetraoxide	O2NNO2 (cr,l)	-37.93	-27.08	± 0.19	kJ/mol	92.0111 ± 0.0012	10544-72-6*500
Oxoniumyl ion	[H2O]+ (g, para)	978.725	975.574	± 0.029	kJ/mol	18.01473 ± 0.00033	56583-62-1*2
Trioxodinitrate anion	[ONNO2]- (g)	-103.0	-106.9	± 2.9	kJ/mol	76.01223 ± 0.00091	194856-62-7*0
Cyanogen bromide cation	[BrCN]+ (g)	1330.3	1324.0	± 1.2	kJ/mol	105.9209 ± 0.0013	34749-77-4*0
Isocyanogen anion	[CNCN]- (g, trans-cis equilib)	383.9	388.0	± 2.5	kJ/mol	52.0354 ± 0.0016	83951-85-30
Hydroxyamidogen	HNOH (g)	101.5	94.7	± 1.0	kJ/mol	32.02202 ± 0.00034	13940-32-4*0
Water	H2O (cr, eq.press.)	-286.299	-292.740	± 0.026	kJ/mol	18.01528 ± 0.00033	7732-18-5*509
Hydrogen peroxide	H2O2 (g, ortho)	-129.447	-135.453	± 0.063	kJ/mol	34.01468 ± 0.00062	7722-84-1*1
Methanediol	CH2(OH)2 (g)	-379.15	-392.55	± 0.96	kJ/mol	48.0413 ± 0.0010	463-57-0*0
Dioxygen difluoride cation	[FOOF]+ (g)	1293.0	1289.8	± 4.6	kJ/mol	69.99506 ± 0.00060	7783-44-00
Diisocyanogen cation	[CNNC]+ (g, trans-cis equilib)	1823.0	1826.0	± 3.5	kJ/mol	52.0343 ± 0.0016	78800-21-20
Fluoroform	CF3H (l)		-704.51	± 0.46	kJ/mol	70.01385 ± 0.00080	75-46-7*590
Ethylene anion	[C2H4]- (g)	236.8	230.3	± 2.2	kJ/mol	28.0537 ± 0.0016	34527-91-8*0
Nitrosyl nitrite	ONONO (g)	91.2	86.6	± 1.6	kJ/mol	76.01168 ± 0.00091	122413-35-8*0
Dioxymethylene	HCOO (g, cis-trans equilib)	332.1	329.9	± 5.9	kJ/mol	45.0174 ± 0.0010	438586-67-5*0
Hydroperoxonium	[H2OOH]+ (g)	738.1	727.8	± 1.0	kJ/mol	35.02207 ± 0.00064	70850-26-9*0
Oxygen atom	O (g, triplet only)	246.844	249.229	± 0.0021	kJ/mol	15.99940 ± 0.00030	17778-80-2*1
Diazene cation	[HNNH]+ (g, trans-cis equilib)	1132.60	1125.69	± 0.74	kJ/mol	30.02881 ± 0.00020	76986-17-9*1
Hydrogen peroxide	H2O2 (aq)		-190.75	± 0.30	kJ/mol	34.01468 ± 0.00062	7722-84-1*800
Methylene fluoride	CH2F2 (l)		-467.26	± 0.40	kJ/mol	52.02339 ± 0.00081	75-10-5*590
Vinyl alcohol	CH2CHOH (g, syn-anti equilib)	-112.59	-122.96	± 0.87	kJ/mol	44.0526 ± 0.0017	557-75-5*0
Hydrogen nitroxylate	[HONO]- (g)	-107.8	-111.3	± 2.0	kJ/mol	47.01403 ± 0.00061	24388-53-2*0
Carbon monoxide	CO (g, triplet only)	465.580	469.287	± 0.026	kJ/mol	28.01010 ± 0.00085	630-08-0*1
Nitrosyl nitrite anion	[ONONO]- (g)	-100.8	-104.0	± 4.4	kJ/mol	76.01223 ± 0.00091	122413-35-80
Ethylidyne	CH3C (g, doublet)	510.3	506.3	± 1.1	kJ/mol	27.0452 ± 0.0016	67624-57-1*1
Vinyl alcohol cation	[CH2CHOH]+ (g, anti-syn equilib)	779.1	768.3	± 1.2	kJ/mol	44.0520 ± 0.0017	57239-63-1*0
Methylidyne	CH (g, doublet)	592.83	596.16	± 0.13	kJ/mol	13.01864 ± 0.00080	3315-37-5*1
Oxirene	O(CHCH) (g)	276.6	276.0	± 3.1	kJ/mol	42.0367 ± 0.0016	157-18-6*0
Hydroxyaminylium	[HNOH]+ (g)	1020.2	1013.0	± 2.0	kJ/mol	32.02147 ± 0.00034	66097-71-0*0
Propynylidene	HCCCH (g, singlet)	597.8	599.6	± 1.5	kJ/mol	38.0480 ± 0.0024	67152-18-5*2
Diiodine cation	[I2]+ (g)	963.523	960.408	± 0.018	kJ/mol	253.808391 ± 0.000060	28712-14-3*0
Diazene cation	[HNNH]+ (g, trans-iso-cis equilib)	1132.60	1125.93	± 0.74	kJ/mol	30.02881 ± 0.00020	76986-17-9*0
Imidogen	NH (g, triplet only)	358.75	358.79	± 0.17	kJ/mol	15.014680 ± 0.000099	13774-92-0*1
Trioxidaniumyl	[HOOOH]+ (g)	927.1	918.2	± 1.4	kJ/mol	50.01353 ± 0.00091	161321-37-5*0
Diazene	HNNH (g, trans-cis-iso equilib)	207.36	200.22	± 0.56	kJ/mol	30.02936 ± 0.00020	3618-05-1*0
Hydrogen peroxide cation	[H2O2]+ (g, cis, ortho)	930.92	924.04	± 0.94	kJ/mol	34.01413 ± 0.00062	12325-10-9*21
Oxirene	O(CHCH) (g, triplet)	390.0	386.6	± 2.8	kJ/mol	42.0367 ± 0.0016	157-18-6*1
2-Hydroxyethyl	CH2CH2OH (g)	-12.75	-26.01	± 0.61	kJ/mol	45.0605 ± 0.0017	4422-54-2*0
Hydrogen peroxide cation	[H2O2]+ (g, trans, para)	896.88	889.87	± 0.57	kJ/mol	34.01413 ± 0.00062	12325-10-9*12
COC vdW	(CO)(C) (g)	589.1	597.8	± 1.8	kJ/mol	40.0208 ± 0.0016	12071-24-80
Iminomethyl	HCNH (g, trans-cis equilib)	276.2	272.6	± 1.4	kJ/mol	28.03332 ± 0.00082	15691-95-9*0
Cyclohexane	C6H12 (g)	-82.51	-122.07	± 0.68	kJ/mol	84.1595 ± 0.0049	110-82-7*0
Imidogen	NH (g, singlet)	509.34	509.39	± 0.18	kJ/mol	15.014680 ± 0.000099	13774-92-0*2
Heptane	C7H16 (g)	-145.47	-187.34	± 0.74	kJ/mol	100.2019 ± 0.0057	142-82-5*0
Dichlorine cation	[Cl2]+ (g)	1107.90	1107.87	± 0.22	kJ/mol	70.9049 ± 0.0018	12595-90-3*0
Octane	C8H18 (g)	-161.40	-208.23	± 0.79	kJ/mol	114.2285 ± 0.0065	111-65-9*0
Hydroperoxonium	[H2OOH]+ (g, cis)	762.5	752.6	± 1.9	kJ/mol	35.02207 ± 0.00064	70850-26-9*2
2,2,4-Trimethylpentane	(CH3)2CHCH2C(CH3)3 (g)	-171.3	-223.7	± 1.5	kJ/mol	114.2285 ± 0.0065	540-84-1*0
Diazene	HNNH (g, trans-cis equilib)	207.36	200.22	± 0.56	kJ/mol	30.02936 ± 0.00020	3618-05-1*1
Dinitrogen anion	[N2]- (g)	196.0	196.0	± 2.2	kJ/mol	28.01403 ± 0.00014	12185-02-3*0
Ethyl chloride	CH3CH2Cl (cr,l)	-134.07	-135.69	± 0.22	kJ/mol	64.5138 ± 0.0019	75-00-3*500
Cyanogen fluoride cation	[FCN]+ (g)	1294.0	1294.7	± 1.2	kJ/mol	45.01529 ± 0.00080	62532-69-8*0
Methyl iodide cation	[CH3I]+ (g)	944.75	935.35	± 0.17	kJ/mol	141.93844 ± 0.00083	12538-72-6*0
Water	H2O (g, ortho)	-238.643	-241.831	± 0.026	kJ/mol	18.01528 ± 0.00033	7732-18-5*1
Isocyanogen fluoride	FNC (g)	299.6	301.4	± 2.3	kJ/mol	45.01584 ± 0.00080	16992-26-0*0
Iodine monochloride	ICl (cr,l)	-36.511	-35.537	± 0.063	kJ/mol	162.35717 ± 0.00090	7790-99-0*500
Dioxygen	O2 (g, triplet only)	0.000	0.000	± 0.000	kJ/mol	31.99880 ± 0.00060	7782-44-7*1
Succinic acid	(CH2COOH)2 (g)	-795.62	-817.76	± 0.61	kJ/mol	118.0880 ± 0.0034	110-15-6*0
Allyl anion	[CH2CHCH2]- (g)	133.40	123.65	± 0.92	kJ/mol	41.0723 ± 0.0024	1724-46-5*0
Trihydrogen cation	[H3]+ (g, ortho)	1110.577	1106.695	± 0.013	kJ/mol	3.02327 ± 0.00021	28132-48-1*1
Hydrogen difluoride cation	[FHF]+ (g)	1255.	1251.	± 20.	kJ/mol	39.004198 ± 0.000070	126950-54-7*0
Iminomethyl anion	[HCNH]- (g)	239.0	235.3	± 2.0	kJ/mol	28.03387 ± 0.00082	90623-30-6*0
Trioxidane	HOOOH (g)	-81.40	-90.00	± 0.78	kJ/mol	50.01408 ± 0.00091	14699-99-1*0
3-Chloro-3-methyl-3H-diazirine	(NNC)ClCH3 (g)	230.	218.	± 40.	kJ/mol	90.5114 ± 0.0019	4222-21-3*0
Methyl fluoride cation	[CH3F]+ (g)	981.09	973.58	± 0.64	kJ/mol	34.03237 ± 0.00083	59122-96-2*0
Methyl fluoride	CH3F (l)		-246.47	± 0.48	kJ/mol	34.03292 ± 0.00083	593-53-3*590
Ethylidene	CH3CH (g)	361.5	354.5	± 1.2	kJ/mol	28.0532 ± 0.0016	4218-50-2*0
Methyl chloride cation	[CH3Cl]+ (g)	1013.80	1006.35	± 0.41	kJ/mol	50.4867 ± 0.0012	12538-71-5*0
C=O-C cation	[COC]+ (g)	1575.9	1583.0	± 2.3	kJ/mol	40.0203 ± 0.0016	83483-98-1*0
Methyl chloride	CH3Cl (l)	-106.54	-102.57	± 0.21	kJ/mol	50.4872 ± 0.0012	74-87-3*590
1,1-Dibromoethane	CHBr2CH3 (cr,l)		-66.3	± 1.4	kJ/mol	187.8612 ± 0.0026	557-91-5*500
Xenon dication	[Xe]+2 (g)	3194.14	3194.14	± 0.36	kJ/mol	131.2889 ± 0.0200	14066-95-6*0
Hydrogen peroxide cation	[H2O2]+ (g)	896.85	889.87	± 0.57	kJ/mol	34.01413 ± 0.00062	12325-10-9*0
Methyl bromide cation	[CH3Br]+ (g)	996.11	981.19	± 0.19	kJ/mol	94.9380 ± 0.0013	12538-70-4*0
Helium cation	He+ (g)	2372.322	2372.322	± 0.000	kJ/mol	4.0020534 ± 0.0000020	14234-48-1*0
Helium dication	[He]+2 (g)	7622.839	7622.839	± 0.000	kJ/mol	4.0015048 ± 0.0000020	12587-46-1*0
Neon cation	Ne+ (g)	2080.662	2080.769	± 0.0011	kJ/mol	20.17915 ± 0.00060	14782-23-1*0
Argon cation	Ar+ (g)	1520.571	1520.580	± 0.0011	kJ/mol	39.9475 ± 0.0010	14791-69-6*0
Krypton cation	Kr+ (g)	1350.759	1350.759	± 0.0011	kJ/mol	83.7995 ± 0.1000	16915-28-9*0

References

1		B. Ruscic, R. E. Pinzon, M. L. Morton, G. von Laszewski, S. Bittner, S. G. Nijsure, K. A. Amin, M. Minkoff, and A. F. Wagner, Introduction to Active Thermochemical Tables: Several "Key" Enthalpies of Formation Revisited. J. Phys. Chem. A 108, 9979-9997 (2004) [DOI: 10.1021/jp047912y]
2		B. Ruscic, R. E. Pinzon, G. von Laszewski, D. Kodeboyina, A. Burcat, D. Leahy, D. Montoya, and A. F. Wagner, Active Thermochemical Tables: Thermochemistry for the 21^st Century. J. Phys. Conf. Ser. 16, 561-570 (2005) [DOI: 10.1088/1742-6596/16/1/078]
3		B. Ruscic, Active Thermochemical Tables (ATcT) values based on ver. 1.118 of the Thermochemical Network (2015); available at ATcT.anl.gov
4		B. Ruscic, Active Thermochemical Tables: Dissociation Energies of Several Homonuclear First-Row Diatomics and Related Thermochemical Values. Theor. Chem. Acc. 133, 1415/1-12 (2005) [DOI: 10.1007/s00214-013-1415-z]
5		S. J. Klippenstein, L. B. Harding, and B. Ruscic, Ab initio Computations and Active Thermochemical Tables Hand in Hand: Heats of Formation of Core Combustion Species. J. Phys. Chem. A in preparation (2016)
6		B. Ruscic, Uncertainty Quantification in Thermochemistry, Benchmarking Electronic Structure Computations, and Active Thermochemical Tables. Int. J. Quantum Chem. 114, 1097-1101 (2014) [DOI: 10.1002/qua.24605]

Formula

The aggregate state is given in parentheses following the formula, such as: g - gas-phase, cr - crystal, l - liquid, etc.

Uncertainties

The listed uncertainties correspond to estimated 95% confidence limits, as customary in thermochemistry (see, for example, Ruscic [6]).
Note that an uncertainty of ± 0.000 kJ/mol indicates that the estimated uncertainty is < ± 0.000₅ kJ/mol.

Search Functionality Credits

The search functionality and the related reorganization of the website was developed and implemented by David H. Bross (ANL).
The find function is based on the Species Dictionary entries for the appropriate version of the ATcT TN.

Acknowledgement

This work was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Chemical Sciences, Geosciences and Biosciences under Contract No. DE-AC02-06CH11357.

Page generated: 04/01/2025

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