ATcT [1, 2] enthalpies of formation based on version 1.122 of the Thermochemical Network [3]

Below is a list of 0 K and 298.15 K enthalpies of formation for all 1199 species included in version 1.122 (as of 09/05/2016).
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, other highly correlated chemical species, and high-leverage reactions in the Thermochemical Network.
(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.)

Species Name:

(case insensitive)

Species Formula:

(case sensitive)

Exact Matches only:

Website functionality credits

The reaction search accepts only the preferred formula, as specified in this version of the Thermochemical Network.
For help finding the current preferred formula of a species, please refer to the species name or species formula searches above.
For convenience clicking the preferred formula adds it to the species list for reaction searches.
The stoichiometry represents fractions as decimals,
e.g. 0.5 O2, 1 H2, 1 H2O would represent
1/2 O2 + H2 → H2O

Species Name	Image	Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
Dihydrogen		0	0	exact		2.01588 ± 0.00014	1333-74-0*0
Helium		0	0	exact		4.0026020 ± 0.0000020	7440-59-7*0
Carbon atom		0	0	exact		12.01070 ± 0.00080	7440-44-0*500
Dinitrogen		0	0	exact		28.01348 ± 0.00014	7727-37-9*0
Dioxygen		0	0	exact		31.99880 ± 0.00060	7782-44-7*0
Difluorine		0	0	exact		37.9968064 ± 0.0000010	7782-41-4*0
Neon		0	0	exact		20.17970 ± 0.00060	7440-01-9*0
Dichlorine		0	0	exact		70.9054 ± 0.0018	7782-50-5*0
Argon		0	0	exact		39.94800 ± 0.00100	7440-37-1*0
Dibromine		0	0	exact		159.8080 ± 0.0020	7726-95-6*500
Krypton		0	0	exact		83.8000 ± 0.1000	7439-90-9*0
Diiodine		0	0	exact		253.808940 ± 0.000060	7553-56-2*500
Xenon		0	0	exact		131.2900 ± 0.0200	7440-63-3*0
Deuterium molecule		0	0	exact		4.02820355600 ± 0.00000000080	7782-39-0*0
Hydrogen atom		216.034	217.998	± 0.000	kJ/mol	1.007940 ± 0.000070	12385-13-6*0
Carbon atom		711.401	716.886	± 0.050	kJ/mol	12.01070 ± 0.00080	7440-44-0*0
Oxygen atom		246.844	249.229	± 0.0021	kJ/mol	15.99940 ± 0.00030	17778-80-2*0
Nitrogen atom		470.577	472.440	± 0.024	kJ/mol	14.006740 ± 0.000070	17778-88-0*0
Carbon dioxide		-393.109	-393.475	± 0.015	kJ/mol	44.00950 ± 0.00100	124-38-9*0
Fluorine atom		77.263	79.369	± 0.048	kJ/mol	18.99840320 ± 0.00000050	14762-94-8*0
Methane		-66.550	-74.520	± 0.057	kJ/mol	16.04246 ± 0.00085	74-82-8*0
Water		-286.300	-285.828	± 0.027	kJ/mol	18.01528 ± 0.00033	7732-18-5*500
Water		-238.931	-241.834	± 0.027	kJ/mol	18.01528 ± 0.00033	7732-18-5*0
Chlorine atom		119.621	121.302	± 0.0011	kJ/mol	35.45270 ± 0.00090	22537-15-1*0
Bromine atom		117.917	111.854	± 0.056	kJ/mol	79.90400 ± 0.00100	10097-32-2*0
Ethane		-68.29	-83.91	± 0.14	kJ/mol	30.0690 ± 0.0017	74-84-0*0
Hydron		1528.084	1530.047	± 0.000	kJ/mol	1.007391 ± 0.000070	12408-02-5*0
Hydroxyl		37.250	37.490	± 0.027	kJ/mol	17.00734 ± 0.00031	3352-57-6*0
Ethylene		60.96	52.45	± 0.13	kJ/mol	28.0532 ± 0.0016	74-85-1*0
Carbon monoxide		-113.803	-110.523	± 0.026	kJ/mol	28.01010 ± 0.00085	630-08-0*0
Hydrogen chloride		-91.989	-92.173	± 0.0062	kJ/mol	36.46064 ± 0.00090	7647-01-0*0
Methyl		149.788	146.374	± 0.080	kJ/mol	15.03452 ± 0.00083	2229-07-4*0
Hydrogen bromide		-27.81	-35.66	± 0.16	kJ/mol	80.9119 ± 0.0010	10035-10-6*0
Methanol		-189.83	-200.71	± 0.16	kJ/mol	32.04186 ± 0.00090	67-56-1*0
Hydrogen fluoride		-272.668	-272.715	± 0.049	kJ/mol	20.006343 ± 0.000070	7664-39-3*0
Iodine atom		107.157	106.757	± 0.0021	kJ/mol	126.904470 ± 0.000030	14362-44-8*0
Formaldehyde		-105.349	-109.188	± 0.099	kJ/mol	30.02598 ± 0.00087	50-00-0*0
Acetylene		228.84	228.28	± 0.14	kJ/mol	26.0373 ± 0.0016	74-86-2*0
Nitric oxide		90.617	91.121	± 0.065	kJ/mol	30.00614 ± 0.00031	10102-43-9*0
Ethanol		-216.89	-234.61	± 0.21	kJ/mol	46.0684 ± 0.0017	64-17-5*0
Methyl chloride		-74.25	-82.18	± 0.25	kJ/mol	50.4872 ± 0.0012	74-87-3*0
Ethyl		130.92	119.86	± 0.28	kJ/mol	29.0611 ± 0.0016	2025-56-1*0
Propane		-82.75	-105.03	± 0.19	kJ/mol	44.0956 ± 0.0025	74-98-6*0
Nitrogen dioxide		36.856	34.049	± 0.065	kJ/mol	46.00554 ± 0.00060	10102-44-0*0
Ammonia		-38.562	-45.554	± 0.030	kJ/mol	17.03056 ± 0.00022	7664-41-7*0
Hydrogen cyanide		129.662	129.277	± 0.091	kJ/mol	27.02538 ± 0.00081	74-90-8*0
Hydrogen iodide		28.641	26.466	± 0.036	kJ/mol	127.912410 ± 0.000076	10034-85-2*0
Methyl fluoride		-227.77	-235.80	± 0.23	kJ/mol	34.03292 ± 0.00083	593-53-3*0
Methyl bromide		-20.36	-35.76	± 0.27	kJ/mol	94.9385 ± 0.0013	74-83-9*0
Hydrogen peroxide		-129.472	-135.457	± 0.064	kJ/mol	34.01468 ± 0.00062	7722-84-1*0
Hydroxyde		-139.091	-139.058	± 0.027	kJ/mol	17.00789 ± 0.00031	14280-30-9*0
Dioxidanyl		15.16	12.26	± 0.16	kJ/mol	33.00674 ± 0.00060	3170-83-0*0
Propylene		35.00	19.99	± 0.22	kJ/mol	42.0797 ± 0.0024	115-07-1*0
Tetrafluoromethane		-927.41	-933.39	± 0.25	kJ/mol	88.00431 ± 0.00080	75-73-0*0
Fluoride		-250.901	-249.117	± 0.048	kJ/mol	18.99895178 ± 0.00000050	16984-48-8*0
Hypochlorous acid		-73.867	-76.807	± 0.028	kJ/mol	52.46004 ± 0.00095	7790-92-3*0
Acetaldehyde		-154.97	-165.45	± 0.28	kJ/mol	44.0526 ± 0.0017	75-07-0*0
Benzene		100.62	83.11	± 0.25	kJ/mol	78.1118 ± 0.0048	71-43-2*0
Dibromine		45.68	30.89	± 0.11	kJ/mol	159.8080 ± 0.0020	7726-95-6*0
Diiodine		65.497	62.417	± 0.0041	kJ/mol	253.808940 ± 0.000060	7553-56-2*0
Methylidyne		592.78	596.12	± 0.11	kJ/mol	13.01864 ± 0.00080	3315-37-5*0
Formic acid		-371.12	-378.45	± 0.22	kJ/mol	46.0254 ± 0.0010	64-18-6*1
Fluoroform		-688.92	-695.87	± 0.43	kJ/mol	70.01385 ± 0.00080	75-46-7*0
Oxonium		605.85	599.10	± 0.17	kJ/mol	19.02267 ± 0.00037	13968-08-6*0
Hypoflorous acid		-84.37	-87.27	± 0.19	kJ/mol	36.00574 ± 0.00031	14034-79-8*0
Hypobromous acid		-51.38	-61.85	± 0.57	kJ/mol	96.9113 ± 0.0010	13517-11-8*0
Methyl iodide		24.48	14.94	± 0.17	kJ/mol	141.93899 ± 0.00083	74-88-4*0
Trifluoromethyl		-465.15	-467.94	± 0.49	kJ/mol	69.00591 ± 0.00080	2264-21-3*0
Propyne		192.80	185.74	± 0.25	kJ/mol	40.0639 ± 0.0024	74-99-7*0
Methylene		390.96	391.52	± 0.12	kJ/mol	14.02658 ± 0.00081	2465-56-7*1
Methylene		428.62	429.03	± 0.13	kJ/mol	14.02658 ± 0.00081	2465-56-7*2
Vinyl		301.11	296.91	± 0.33	kJ/mol	27.0452 ± 0.0016	2669-89-8*0
Ketene		-45.45	-48.57	± 0.13	kJ/mol	42.0367 ± 0.0016	463-51-4*0
Tetrachloromethane		-94.27	-96.44	± 0.64	kJ/mol	153.8215 ± 0.0037	56-23-5*0
Imidogen		358.73	358.77	± 0.17	kJ/mol	15.014680 ± 0.000099	13774-92-0*0
Allene		197.34	189.86	± 0.26	kJ/mol	40.0639 ± 0.0024	463-49-0*0
n-Butane		-98.63	-125.94	± 0.27	kJ/mol	58.1222 ± 0.0033	106-97-8*0
Difluorophosgene		-603.50	-606.59	± 0.46	kJ/mol	66.00691 ± 0.00085	353-50-4*0
Bromide		-206.620	-212.683	± 0.056	kJ/mol	79.90455 ± 0.00100	24959-67-9*0
Oxomethylium		827.802	827.217	± 0.099	kJ/mol	29.01749 ± 0.00086	17030-74-9*0
Iodide		-187.995	-188.396	± 0.0021	kJ/mol	126.905019 ± 0.000030	20461-54-5*0
Nitric acid		-124.48	-134.20	± 0.18	kJ/mol	63.01288 ± 0.00091	7697-37-2*0
Formyl		41.426	41.803	± 0.099	kJ/mol	29.01804 ± 0.00086	2597-44-6*0
Hydroxymethyl		-10.25	-16.56	± 0.33	kJ/mol	31.03392 ± 0.00088	2597-43-5*0
Chloroxyl radical		101.124	101.715	± 0.035	kJ/mol	51.45210 ± 0.00095	14989-30-1*0
Methylium		1099.243	1095.299	± 0.078	kJ/mol	15.03397 ± 0.00083	14531-53-4*0
Ozone		144.396	141.733	± 0.039	kJ/mol	47.99820 ± 0.00090	10028-15-6*0
Cyanogen chloride		135.03	135.72	± 0.44	kJ/mol	61.4701 ± 0.0012	506-77-4*0
Phenyl		350.37	337.08	± 0.57	kJ/mol	77.1039 ± 0.0048	2396-01-2*0
Ethylium		915.03	902.95	± 0.32	kJ/mol	29.0606 ± 0.0016	14936-94-8*0
Methoxide		-122.54	-130.27	± 0.35	kJ/mol	31.03447 ± 0.00088	3315-60-4*0
Methoxy		28.90	21.53	± 0.34	kJ/mol	31.03392 ± 0.00088	2143-68-2*0
Tetrabromomethane		131.5	101.8	± 1.1	kJ/mol	331.6267 ± 0.0041	558-13-4*0
Oxygen atom anion		105.868	108.097	± 0.0021	kJ/mol	15.99995 ± 0.00030	14337-01-0*0
Nitrilomethyl		436.73	440.01	± 0.15	kJ/mol	26.01744 ± 0.00080	2074-87-5*0
Cyanogen fluoride		8.88	9.21	± 0.68	kJ/mol	45.01584 ± 0.00080	1495-50-7*0
Chloride		-228.953	-227.346	± 0.0021	kJ/mol	35.45325 ± 0.00090	16887-00-6*0
Trihydrogen cation		1110.304	1106.696	± 0.013	kJ/mol	3.02327 ± 0.00021	28132-48-1*0
Cyanogen bromide		187.41	180.62	± 0.73	kJ/mol	105.9214 ± 0.0013	506-68-3*0
Methylene fluoride		-443.16	-450.73	± 0.36	kJ/mol	52.02339 ± 0.00081	75-10-5*0
2-Propynyl		354.00	351.44	± 0.38	kJ/mol	39.0559 ± 0.0024	2932-78-7*0
Propynylidene		543.38	546.38	± 0.63	kJ/mol	38.0480 ± 0.0024	67152-18-5*1
Dioxymethyl	$[O-]\[O+]=C$	112.43	105.42	± 0.61	kJ/mol	46.0254 ± 0.0010	56077-92-0*0
Oxygen atom cation		1560.786	1562.644	± 0.0021	kJ/mol	15.99885 ± 0.00030	14581-93-2*0
Hypochlorite		-118.60	-118.33	± 0.13	kJ/mol	51.45265 ± 0.00095	14380-61-1*0
1,2-Propadiene-1,3-diylidene		814.52	823.48	± 0.54	kJ/mol	36.0321 ± 0.0024	12075-35-3*0
Allyl		179.56	167.84	± 0.54	kJ/mol	41.0718 ± 0.0024	1981-80-2*0
1-Hydroxyethyl		-42.16	-55.59	± 0.61	kJ/mol	45.0605 ± 0.0017	2348-46-1*1
2-Hydroxyethyl		-12.79	-26.06	± 0.61	kJ/mol	45.0605 ± 0.0017	4422-54-2*1
Ethyl chloride		-96.76	-111.35	± 0.20	kJ/mol	64.5138 ± 0.0019	75-00-3*0
Hydride		143.264	145.228	± 0.000	kJ/mol	1.008489 ± 0.000070	12184-88-2*0
Oxygen difluoride		26.94	24.69	± 0.25	kJ/mol	53.99621 ± 0.00030	7783-41-7*0
Methylenimine		96.53	88.62	± 0.63	kJ/mol	29.04126 ± 0.00083	2053-29-4*0
Methylamine		-5.97	-21.05	± 0.46	kJ/mol	31.05714 ± 0.00088	74-89-5*0
Nitrite		-182.69	-185.50	± 0.45	kJ/mol	46.00609 ± 0.00060	14797-65-0*0
Nitrosyl hydride		109.93	106.96	± 0.11	kJ/mol	31.01408 ± 0.00032	14332-28-6*0
Nitrous acid		-73.018	-79.162	± 0.079	kJ/mol	47.01348 ± 0.00061	7782-77-6*1
Ethynylene		820.21	828.68	± 0.27	kJ/mol	24.0214 ± 0.0016	12070-15-4*0
Ethynyl		563.87	567.99	± 0.15	kJ/mol	25.0293 ± 0.0016	2122-48-7*0
Ethoxide		-164.11	-179.05	± 0.52	kJ/mol	45.0610 ± 0.0017	16331-64-9*0
Chloroform		-98.49	-103.39	± 0.64	kJ/mol	119.3767 ± 0.0028	67-66-3*0
Methylene chloride		-87.85	-94.71	± 0.59	kJ/mol	84.9320 ± 0.0020	75-09-2*0
Tetrafluoroethylene		-671.52	-674.93	± 0.57	kJ/mol	100.0150 ± 0.0016	116-14-3*0
Phenylium		1148.47	1136.57	± 0.89	kJ/mol	77.1034 ± 0.0048	17333-73-2*0
Hypoiodous acid		-56.6	-61.3	± 2.0	kJ/mol	143.91181 ± 0.00031	14332-21-9*0
Amidogen		188.91	186.02	± 0.12	kJ/mol	16.02262 ± 0.00016	13770-40-6*0
Methanium		922.07	911.83	± 0.44	kJ/mol	17.04985 ± 0.00087	15135-49-6*0
Hydroxylamine		-33.12	-43.50	± 0.49	kJ/mol	33.02996 ± 0.00037	7803-49-8*1
Oxirane		-40.00	-52.54	± 0.38	kJ/mol	44.0526 ± 0.0017	75-21-8*0
Methyl hydroperoxide		-114.90	-127.72	± 0.74	kJ/mol	48.0413 ± 0.0010	3031-73-0*0
Hydroxyformyl		-180.96	-183.93	± 0.48	kJ/mol	45.0174 ± 0.0010	2564-86-5*1
Isocyanic acid		-115.85	-118.85	± 0.31	kJ/mol	43.02478 ± 0.00086	75-13-8*0
Tetraiodomethane		340.8	335.7	± 1.3	kJ/mol	519.62858 ± 0.00081	507-25-5*0
Chlorotrifluoromethane		-704.97	-710.08	± 0.72	kJ/mol	104.4586 ± 0.0012	75-72-9*0
Bromotrifluoromethane		-639.45	-651.57	± 0.50	kJ/mol	148.9099 ± 0.0013	75-63-8*0
Fluoromethylidyne		243.11	246.71	± 0.13	kJ/mol	31.00910 ± 0.00080	3889-75-6*0
Fluoroxyl radical		110.26	110.88	± 0.15	kJ/mol	34.99780 ± 0.00030	12061-70-0*0
Dioxygen cation		1164.585	1165.221	± 0.0092	kJ/mol	31.99825 ± 0.00060	12185-07-8*0
Methylidyne		664.55	667.88	± 0.59	kJ/mol	13.01864 ± 0.00080	3315-37-5*2
Ethoxy		1.16	-12.74	± 0.51	kJ/mol	45.0605 ± 0.0017	2154-50-9*51
Cyanato		127.02	127.49	± 0.35	kJ/mol	42.01684 ± 0.00086	22400-26-6*0
Phosgene		-217.43	-219.13	± 0.27	kJ/mol	98.9155 ± 0.0020	75-44-5*0
Bromoform		74.3	48.1	± 1.3	kJ/mol	252.7306 ± 0.0031	75-25-2*0
Vinyl chloride		29.57	22.10	± 0.34	kJ/mol	62.4979 ± 0.0018	75-01-4*0
Acetone		-199.45	-216.14	± 0.36	kJ/mol	58.0791 ± 0.0025	67-64-1*0
Hydrogen fluoride			-334.51	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*800
Hypobromite		-96.24	-103.73	± 0.55	kJ/mol	95.9039 ± 0.0010	14380-62-2*0
Diazenylium		1042.78	1039.17	± 0.73	kJ/mol	29.02087 ± 0.00016	12357-66-3*0
Peroxynitrous acid		-5.99	-14.43	± 0.36	kJ/mol	63.01288 ± 0.00091	14691-52-2*3
Dioxygenyl fluoride		26.75	25.04	± 0.27	kJ/mol	50.99720 ± 0.00060	15499-23-7*0
Cyclopropane		70.80	53.65	± 0.46	kJ/mol	42.0797 ± 0.0024	75-19-4*0
Propadienylidene		554.45	555.59	± 0.42	kJ/mol	38.0480 ± 0.0024	60731-10-4*0
Acetyl		-3.31	-9.97	± 0.37	kJ/mol	43.0446 ± 0.0016	3170-69-2*0
Methylperoxy		22.29	12.54	± 0.49	kJ/mol	47.0333 ± 0.0010	2143-58-0*0
Ethyl fluoride		-257.30	-272.16	± 0.37	kJ/mol	48.0595 ± 0.0016	353-36-6*0
Ethyl bromide		-41.14	-63.09	± 0.26	kJ/mol	108.9651 ± 0.0019	74-96-4*0
Vinyl fluoride		-134.71	-142.51	± 0.47	kJ/mol	46.0436 ± 0.0016	75-02-5*0
Vinyl bromide		88.82	74.01	± 0.59	kJ/mol	106.9492 ± 0.0019	593-60-2*0
2-Bromoethanol		-196.57	-220.63	± 0.54	kJ/mol	124.9645 ± 0.0019	540-51-2*0
Fluorobenzene		-99.29	-114.97	± 0.83	kJ/mol	96.1023 ± 0.0048	462-06-6*0
Nitromethane		-60.86	-74.76	± 0.47	kJ/mol	61.0401 ± 0.0010	75-52-5*0
Dioxidanide		-88.86	-91.52	± 0.38	kJ/mol	33.00729 ± 0.00060	14691-59-9*0
Nitrous oxide		85.998	82.568	± 0.097	kJ/mol	44.01288 ± 0.00033	10024-97-2*0
(E)-Diazene		207.35	200.20	± 0.44	kJ/mol	30.02936 ± 0.00020	15626-43-4*0
Hydroxyoxomethylium		600.76	597.68	± 0.43	kJ/mol	45.0169 ± 0.0010	638-71-1*0
Vinylium		1119.20	1115.75	± 0.57	kJ/mol	27.0447 ± 0.0016	14604-48-9*0
Hydroxymethylium		717.85	709.91	± 0.19	kJ/mol	31.03337 ± 0.00088	18682-95-6*0
Cyanogen		308.18	310.12	± 0.43	kJ/mol	52.0349 ± 0.0016	460-19-5*0
Cyanogen iodide		222.47	221.95	± 0.99	kJ/mol	152.92191 ± 0.00080	506-78-5*0
iso-Propyl		105.28	88.68	± 0.67	kJ/mol	43.0877 ± 0.0024	2025-55-0*0
Ethynide		277.42	280.83	± 0.19	kJ/mol	25.0299 ± 0.0016	29075-95-4*0
iso-Butane		-106.17	-134.78	± 0.33	kJ/mol	58.1222 ± 0.0033	75-28-5*0
n-Pentane		-114.47	-146.34	± 0.31	kJ/mol	72.1488 ± 0.0041	109-66-0*0
2-Chloroethanol		-250.03	-266.74	± 0.61	kJ/mol	80.5132 ± 0.0019	107-07-3*0
Hypofluorite		-108.90	-108.73	± 0.48	kJ/mol	34.99835 ± 0.00030	12763-66-5*0
Hydrogen chloride			-166.454	± 0.024	kJ/mol	36.46064 ± 0.00090	7647-01-0*834
Bromoxyl radical		131.12	123.59	± 0.29	kJ/mol	95.9034 ± 0.0010	15656-19-6*0
Hydroxyamidogen		101.5	94.7	± 1.0	kJ/mol	32.02202 ± 0.00034	13940-32-4*1
Nitrate		-300.25	-306.72	± 0.61	kJ/mol	62.00549 ± 0.00090	14797-55-8*0
Water			-285.828	± 0.027	kJ/mol	18.01528 ± 0.00033	7732-18-5*590
Formyl anion		11.62	12.01	± 0.43	kJ/mol	29.01859 ± 0.00086	57340-31-5*0
Propyl		117.92	100.81	± 0.61	kJ/mol	43.0877 ± 0.0024	2143-61-5*0
2-Propynylidyne		717.95	722.30	± 0.81	kJ/mol	37.0400 ± 0.0024	53590-28-6*0
Dicarbon monoxide		454.95	459.28	± 0.88	kJ/mol	40.0208 ± 0.0016	12071-23-7*2
Methanetetraylbisamidogen		450.39	450.80	± 0.68	kJ/mol	40.02418 ± 0.00081	2669-76-3*0
Methylene bromide		24.9	3.5	± 1.1	kJ/mol	173.8346 ± 0.0022	74-95-3*0
2-Fluoroethanol		-406.8	-424.0	± 1.1	kJ/mol	64.0589 ± 0.0017	371-62-0*0
Phenide		244.70	231.79	± 0.43	kJ/mol	77.1044 ± 0.0048	30922-78-2*0
Bromobenzene		126.5	104.5	± 1.3	kJ/mol	157.0079 ± 0.0049	108-86-1*0
Hydrogen bromide			-120.80	± 0.16	kJ/mol	80.9119 ± 0.0010	10035-10-6*800
Iodine monochloride		19.024	17.391	± 0.013	kJ/mol	162.35717 ± 0.00090	7790-99-0*0
Iodotrifluoromethane		-583.99	-589.87	± 0.54	kJ/mol	195.91038 ± 0.00080	2314-97-8*0
Nitrogen atom cation		1872.905	1875.687	± 0.024	kJ/mol	14.006191 ± 0.000070	14158-23-7*0
Azido radical		452.24	449.65	± 0.58	kJ/mol	42.02022 ± 0.00021	12596-60-0*0
Trinitrogen cation		1519.39	1516.86	± 0.87	kJ/mol	42.01967 ± 0.00021	12185-03-4*0
Oxonitrate anion		87.91	87.94	± 0.12	kJ/mol	30.00669 ± 0.00031	14967-78-3*0
Carbon monoxide cation		1238.307	1241.586	± 0.026	kJ/mol	28.00955 ± 0.00085	12144-04-6*0
Nitrosyl ion		984.485	984.479	± 0.065	kJ/mol	30.00559 ± 0.00031	14452-93-8*0
Nitroxyl		71.34	64.73	± 0.85	kJ/mol	32.02202 ± 0.00034	13408-29-2*0
Hydrazoic acid		297.92	291.62	± 0.48	kJ/mol	43.02816 ± 0.00022	7782-79-8*0
Ethonium		874.54	858.27	± 0.61	kJ/mol	31.0764 ± 0.0017	24669-33-8*1
Acetylium		667.18	660.02	± 0.65	kJ/mol	43.0441 ± 0.0016	15762-07-9*0
Hydroxymethylene		112.40	108.63	± 0.33	kJ/mol	30.02598 ± 0.00087	19710-56-6*1
Carbonic acid		-602.78	-612.96	± 0.79	kJ/mol	62.0248 ± 0.0012	463-79-6*1
1-Butene		20.88	-0.08	± 0.38	kJ/mol	56.1063 ± 0.0032	106-98-9*0
n-Hexane		-130.06	-166.93	± 0.34	kJ/mol	86.1754 ± 0.0049	110-54-3*0
1-Hydroxyethylium		609.14	594.72	± 0.39	kJ/mol	45.0600 ± 0.0017	18682-96-7*1
Ethoxy		5.41	-9.02	± 0.52	kJ/mol	45.0605 ± 0.0017	2154-50-9*52
Dicarbon monoxide		376.30	380.34	± 0.97	kJ/mol	40.0208 ± 0.0016	12071-23-7*1
Formic acid		-354.76	-362.00	± 0.38	kJ/mol	46.0254 ± 0.0010	64-18-6*2
Formyloxidanyl		-124.76	-126.43	± 0.55	kJ/mol	45.0174 ± 0.0010	16499-21-1*1
Formate		-462.11	-465.75	± 0.55	kJ/mol	45.0180 ± 0.0010	71-47-6*0
Chlorodifluoromethane		-476.5	-482.6	± 1.2	kJ/mol	86.4681 ± 0.0012	75-45-6*0
Fluoromethylene		148.26	148.54	± 0.44	kJ/mol	32.01704 ± 0.00080	13453-52-6*2
Fluoroformyl		-176.70	-176.12	± 0.38	kJ/mol	47.00850 ± 0.00085	1871-24-5*0
Benzaldehyde		-19.16	-36.96	± 0.92	kJ/mol	106.1219 ± 0.0056	100-52-7*0
Chlorobenzene		67.13	52.18	± 0.61	kJ/mol	112.5566 ± 0.0049	108-90-7*0
Hydrogen chloride			-166.994	± 0.023	kJ/mol	36.46064 ± 0.00090	7647-01-0*800
Bromonium		925.4	914.7	± 1.2	kJ/mol	81.9193 ± 0.0010	36658-54-5*0
Hydrogen peroxide cation		896.87	889.88	± 0.57	kJ/mol	34.01413 ± 0.00062	12325-10-9*1
Amide		114.88	112.00	± 0.33	kJ/mol	16.02317 ± 0.00016	17655-31-1*0
Hydrazine		111.84	97.68	± 0.49	kJ/mol	32.04524 ± 0.00031	302-01-2*0
Fluoronium		774.42	771.47	± 0.85	kJ/mol	21.01373 ± 0.00014	12206-67-6*0
Methanide		146.05	142.61	± 0.91	kJ/mol	15.03507 ± 0.00083	15194-58-8*0
Trioxidane		-81.43	-90.27	± 0.70	kJ/mol	50.01408 ± 0.00091	14699-99-1*1
Ethylidene		361.45	354.45	± 0.82	kJ/mol	28.0532 ± 0.0016	4218-50-2*1
Peroxyformic acid		-279.8	-289.1	± 1.1	kJ/mol	62.0248 ± 0.0012	107-32-4*1
1-Methylethenyl		262.90	252.56	± 0.71	kJ/mol	41.0718 ± 0.0024	15552-77-9*0
Isobutene		3.92	-17.15	± 0.44	kJ/mol	56.1063 ± 0.0032	115-11-7*0
trans-2-Butene		9.26	-11.30	± 0.41	kJ/mol	56.1063 ± 0.0032	624-64-6*0
cis-2-Butene	$C/C=C\C$	13.95	-7.32	± 0.42	kJ/mol	56.1063 ± 0.0032	590-18-1*0
1,3-Butadiene		125.05	110.57	± 0.42	kJ/mol	54.0904 ± 0.0032	106-99-0*0
Cyclopentane		-45.01	-77.58	± 0.44	kJ/mol	70.1329 ± 0.0041	287-92-3*0
1,3-Cyclopentadiene		149.88	132.76	± 0.76	kJ/mol	66.1011 ± 0.0040	542-92-7*0
1-Hydroxyethyl		-40.65	-54.12	± 0.86	kJ/mol	45.0605 ± 0.0017	2348-46-1*2
Protonated oxirane		725.29	709.12	± 0.64	kJ/mol	45.0600 ± 0.0017	38607-31-70
Oxoethenyl		176.85	177.97	± 0.60	kJ/mol	41.0287 ± 0.0016	51095-15-9*0
Methanediol		-379.05	-393.25	± 0.95	kJ/mol	48.0413 ± 0.0010	463-57-0*1
Acetyl chloride		-232.68	-241.55	± 0.33	kJ/mol	78.4973 ± 0.0019	75-36-5*0
Methyl formate		-344.75	-357.80	± 0.58	kJ/mol	60.0520 ± 0.0017	107-31-3*1
Trioxidanide		-121.0	-124.0	± 1.4	kJ/mol	49.00669 ± 0.00090	89965-38-8*2
Difluorodichloromethane		-490.69	-495.46	± 0.97	kJ/mol	120.9129 ± 0.0020	75-71-8*0
Fluorodichloromethane		-278.9	-284.2	± 1.2	kJ/mol	102.9224 ± 0.0020	75-43-4*0
Trifluoromethylium		409.00	405.93	± 0.51	kJ/mol	69.00536 ± 0.00080	18851-76-8*0
Methyl nitrite		-55.46	-67.24	± 0.46	kJ/mol	61.0401 ± 0.0010	624-91-9*2
Dichlorine monoxide		79.76	77.95	± 0.36	kJ/mol	86.9048 ± 0.0018	7791-21-1*0
Chlorine peroxide		134.51	131.28	± 0.56	kJ/mol	102.9042 ± 0.0019	12292-23-8*0
Iodoxyl radical		127.0	125.0	± 1.1	kJ/mol	142.90387 ± 0.00030	14696-98-1*0
Dinitrogen cation		1503.311	1503.312	± 0.0011	kJ/mol	28.01293 ± 0.00014	13966-04-6*0
Carbon dioxide cation		936.092	936.927	± 0.017	kJ/mol	44.00895 ± 0.00100	12181-61-2*0
Nitrogen sesquioxide		90.72	86.15	± 0.15	kJ/mol	76.01168 ± 0.00091	10544-73-7*0
Ammonium		643.05	631.74	± 0.21	kJ/mol	18.03795 ± 0.00029	14798-03-9*0
Chloronium		881.29	878.19	± 0.97	kJ/mol	37.46803 ± 0.00091	36658-55-6*0
Ammonium			-133.077	± 0.056	kJ/mol	18.03795 ± 0.00029	14798-03-9*800
Hydrazyl		235.28	224.62	± 0.83	kJ/mol	31.03730 ± 0.00025	13598-46-4*0
Dioxygen difluoride		33.66	29.93	± 0.50	kJ/mol	69.99561 ± 0.00060	7783-44-0*0
Ethylidene		373.93	366.70	± 0.86	kJ/mol	28.0532 ± 0.0016	4218-50-2*2
Hydrogen isocyanide cation		1352.7	1352.7	± 1.2	kJ/mol	27.02483 ± 0.00081	74158-11-5*0
Propargylenide		434.6	437.1	± 1.1	kJ/mol	38.0485 ± 0.0024	82906-05-6*1
2-Hydroxyethyl		-10.04	-22.67	± 0.85	kJ/mol	45.0605 ± 0.0017	4422-54-2*2
Dimethyl ether		-166.50	-184.01	± 0.44	kJ/mol	46.0684 ± 0.0017	115-10-6*0
Methanediol		-368.51	-381.66	± 0.99	kJ/mol	48.0413 ± 0.0010	463-57-0*2
Dichloride		-230.4	-229.3	± 1.4	kJ/mol	70.9059 ± 0.0018	12595-89-0*0
Chlorine dioxide		101.03	98.56	± 0.30	kJ/mol	67.4515 ± 0.0011	10049-04-4*0
Hydroperoxonium		738.17	727.91	± 0.98	kJ/mol	35.02207 ± 0.00064	70850-26-9*1
Formyl fluoride		-378.72	-382.31	± 0.33	kJ/mol	48.01644 ± 0.00086	1493-02-3*0
Nitric acid			-206.63	± 0.18	kJ/mol	63.01288 ± 0.00091	7697-37-2*800
Hydrogen fluoride			-321.06	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*818
Oxoammoniumyl		1092.62	1089.69	± 0.67	kJ/mol	31.01353 ± 0.00032	63559-87-5*0
Difluoride		-290.8	-290.0	± 1.4	kJ/mol	37.9973550 ± 0.0000010	12184-85-9*0
Peroxynitrous acid		7.67	0.59	± 0.40	kJ/mol	63.01288 ± 0.00091	14691-52-2*1
Vinylidene		411.29	412.20	± 0.33	kJ/mol	26.0373 ± 0.0016	2143-69-3*0
Ethylidyne		508.58	504.88	± 0.87	kJ/mol	27.0452 ± 0.0016	67624-57-1*0
Ethylidyne		640.6	636.1	± 1.2	kJ/mol	27.0452 ± 0.0016	67624-57-1*2
Iminomethyl cation		953.3	949.3	± 1.5	kJ/mol	28.03277 ± 0.00082	196216-36-1*0
Chlorine superoxide		103.82	102.73	± 0.37	kJ/mol	67.4515 ± 0.0011	17376-09-9*0
Water dimer		-491.082	-499.121	± 0.053	kJ/mol	36.03056 ± 0.00066	25655-83-8*0
iso-Propylium		822.88	805.62	± 0.26	kJ/mol	43.0871 ± 0.0024	19252-53-0*0
Trioxidane		-72.03	-80.52	± 0.81	kJ/mol	50.01408 ± 0.00091	14699-99-1*2
1-Propenyl		277.98	267.19	± 0.79	kJ/mol	41.0718 ± 0.0024	6067-68-1*2
1-Propynyl		529.00	526.64	± 0.81	kJ/mol	39.0559 ± 0.0024	89342-91-6*0
Propargylenide		437.0	439.5	± 1.1	kJ/mol	38.0485 ± 0.0024	82906-05-6*2
2-Propyn-1-ylium-1-ylidene		1598.0	1602.9	± 1.3	kJ/mol	37.0395 ± 0.0024	75104-46-0*0
2-Butyne		158.96	146.00	± 0.59	kJ/mol	54.0904 ± 0.0032	503-17-3*0
1-Butyne		179.36	165.77	± 0.67	kJ/mol	54.0904 ± 0.0032	107-00-6*0
iso-Pentane		-119.22	-153.27	± 0.44	kJ/mol	72.1488 ± 0.0041	78-78-4*0
Chlorine fluoride		-55.612	-55.707	± 0.055	kJ/mol	54.45110 ± 0.00090	7790-89-8*0
2-Hydroxyethyl		-5.1	-17.5	± 1.2	kJ/mol	45.0605 ± 0.0017	4422-54-2*3
Vinoxy		22.46	15.62	± 0.77	kJ/mol	43.0446 ± 0.0016	6912-06-7*0
Acetyl anion		-43.8	-49.4	± 1.3	kJ/mol	43.0452 ± 0.0016	78944-68-0*0
Ketene		182.5	177.5	± 1.1	kJ/mol	42.0367 ± 0.0016	463-51-4*1
Formic acid		-371.12	-378.42	± 0.22	kJ/mol	46.0254 ± 0.0010	64-18-6*0
Hydroxyformyl		-174.04	-177.07	± 0.51	kJ/mol	45.0174 ± 0.0010	2564-86-5*2
Hydroxyformyl anion		-319.36	-322.13	± 0.58	kJ/mol	45.0180 ± 0.0010	78944-70-4*2
Fluorotrichloromethane		-286.9	-290.1	± 1.2	kJ/mol	137.3672 ± 0.0028	75-69-4*0
Bromotrichloromethane		-33.82	-42.97	± 0.71	kJ/mol	198.2728 ± 0.0030	75-62-7*0
Difluoromethylene		-193.99	-193.51	± 0.38	kJ/mol	50.00751 ± 0.00080	2154-59-8*0
Fluoromethylene		210.12	210.45	± 0.68	kJ/mol	32.01704 ± 0.00080	13453-52-6*1
Hexafluoroethane		-1334.5	-1342.8	± 1.5	kJ/mol	138.0118 ± 0.0016	76-16-4*0
1,1-Difluoroethane		-489.09	-502.81	± 0.65	kJ/mol	66.0500 ± 0.0016	75-37-6*0
2-Hydrotrioxy		300.9	295.2	± 1.1	kJ/mol	49.00614 ± 0.00090	12500-78-60
1,1-Difluoroethene		-343.72	-350.78	± 0.85	kJ/mol	64.0341 ± 0.0016	75-38-7*0
Tricarbon dioxide		-96.2	-94.1	± 1.2	kJ/mol	68.0309 ± 0.0025	504-64-3*0
Iodobenzene		177.6	161.6	± 1.0	kJ/mol	204.0084 ± 0.0048	591-50-4*0
Iodine monobromide		49.717	40.770	± 0.067	kJ/mol	206.8085 ± 0.0010	7789-33-5*0
Nitrosyl nitrite		92.6	87.5	± 1.2	kJ/mol	76.01168 ± 0.00091	122413-35-8*1
Nitroxyl		79.38	74.13	± 0.19	kJ/mol	62.00494 ± 0.00090	12033-49-7*0
Isodiazene		307.99	300.93	± 0.75	kJ/mol	30.02936 ± 0.00020	28647-38-3*0
Nitryl hydride		-37.2	-44.2	± 1.5	kJ/mol	47.01348 ± 0.00061	90266-90-3*0
Carbon atom cation		1797.854	1803.452	± 0.050	kJ/mol	12.01015 ± 0.00080	14067-05-1*0
Methyliumyl		1393.09	1393.95	± 0.13	kJ/mol	14.02603 ± 0.00081	15091-72-2*0
Oxygen atom		436.666	438.523	± 0.0021	kJ/mol	15.99940 ± 0.00030	17778-80-2*2
Methyliumylidene		1619.758	1623.102	± 0.057	kJ/mol	13.01809 ± 0.00080	24361-82-8*0
Methylidyne anion		475.47	478.79	± 0.91	kJ/mol	13.01919 ± 0.00080	28604-54-8*0
Ozonide		-58.48	-60.83	± 0.21	kJ/mol	47.99875 ± 0.00090	12596-80-4*0
(E)-Iminomethyl		275.92	272.30	± 0.84	kJ/mol	28.03332 ± 0.00082	54980-10-8*0
Nitrilomethylium		1778.3	1781.8	± 1.2	kJ/mol	26.01689 ± 0.00080	12539-57-0*0
Fluoroacetylene		104.73	105.45	± 0.41	kJ/mol	44.0277 ± 0.0016	2713-09-9*0
Chloroacetylene		228.3	229.2	± 1.1	kJ/mol	60.4820 ± 0.0018	593-63-5*0
Methanol cation		857.08	846.75	± 0.33	kJ/mol	32.04131 ± 0.00090	12538-91-9*0
Methyloxonium		589.9	575.7	± 1.2	kJ/mol	33.04925 ± 0.00092	17836-08-7*0
Hydroxyde			-230.012	± 0.029	kJ/mol	17.00789 ± 0.00031	14280-30-9*800
Oxidanylium		1293.189	1293.218	± 0.035	kJ/mol	17.00679 ± 0.00031	12259-29-9*0
Carbonic acid		-596.93	-607.04	± 0.85	kJ/mol	62.0248 ± 0.0012	463-79-6*2
Carbonic acid		-561.70	-570.55	± 0.98	kJ/mol	62.0248 ± 0.0012	463-79-6*3
1,2-Propadienyl anion		265.85	262.65	± 0.72	kJ/mol	39.0565 ± 0.0024	64066-06-4*0
1-Propynyl anion		265.06	261.59	± 0.81	kJ/mol	39.0565 ± 0.0024	36147-87-2*0
Bromine monochloride		21.880	14.437	± 0.060	kJ/mol	115.3567 ± 0.0013	13863-41-7*0
neo-Pentane		-134.64	-167.52	± 0.41	kJ/mol	72.1488 ± 0.0041	463-82-1*0
Cyclohexane		-83.59	-123.15	± 0.36	kJ/mol	84.1595 ± 0.0049	110-82-7*0
2-Hydroxyethylium		1019.6	1006.8	± 1.6	kJ/mol	45.0600 ± 0.0017	38607-31-7*3
Vinyl alcohol		-112.55	-123.86	± 0.84	kJ/mol	44.0526 ± 0.0017	557-75-5*1
Ethynol		94.9	92.8	± 1.3	kJ/mol	42.0367 ± 0.0016	32038-79-2*0
Hydroxyformyl anion		-313.53	-315.48	± 0.59	kJ/mol	45.0180 ± 0.0010	78944-70-4*1
1-Propanol		-231.38	-255.22	± 0.26	kJ/mol	60.0950 ± 0.0025	71-23-8*0
2-Propanol		-248.77	-272.87	± 0.36	kJ/mol	60.0950 ± 0.0025	67-63-0*0
Acetic acid		-418.38	-432.50	± 0.54	kJ/mol	60.0520 ± 0.0017	64-19-7*1
Ethylene glycol		-369.80	-389.43	± 0.49	kJ/mol	62.0678 ± 0.0018	107-21-1*0
Fluorochloromethane		-256.4	-263.6	± 1.3	kJ/mol	68.4777 ± 0.0012	593-70-4*0
Chlorine atom cation		1370.806	1372.602	± 0.0011	kJ/mol	35.45215 ± 0.00090	24203-47-2*0
Trioxidanyl		25.31	23.33	± 0.13	kJ/mol	49.00614 ± 0.00090	12500-78-6*1
1,3-Butadiyne		458.57	460.30	± 0.86	kJ/mol	50.0587 ± 0.0032	460-12-8*0
Toluene		73.56	50.27	± 0.36	kJ/mol	92.1384 ± 0.0056	108-88-3*0
Fluorobenzene cation		788.69	774.00	± 0.83	kJ/mol	96.1018 ± 0.0048	34468-25-2*0
Nitromethyl		138.8	129.4	± 1.2	kJ/mol	60.0321 ± 0.0010	16787-85-2*0
Dinitrogen pentoxide		24.41	14.84	± 0.35	kJ/mol	108.0105 ± 0.0015	10102-03-1*0
Water anion		30.5	29.0	± 2.5	kJ/mol	18.01583 ± 0.00033	12259-30-2*100
Bromonium		1257.777	1251.714	± 0.056	kJ/mol	79.90345 ± 0.00100	22541-56-6*0
Peroxynitric acid		-42.6	-54.1	± 1.3	kJ/mol	79.0123 ± 0.0012	26404-66-0*0
Nitrosyl chloride		54.451	52.549	± 0.067	kJ/mol	65.45884 ± 0.00095	2696-92-6*0
Carbon dioxide		49.48	50.33	± 0.99	kJ/mol	44.00950 ± 0.00100	124-38-9*1
Methane cation		1150.84	1144.45	± 0.25	kJ/mol	16.04191 ± 0.00085	20741-88-2*0
Ethonium		874.54	858.30	± 0.61	kJ/mol	31.0764 ± 0.0017	24669-33-8*0
Vinyl anion		237.24	232.82	± 0.84	kJ/mol	27.0458 ± 0.0016	25012-81-1*0
Acetylene cation		1328.85	1328.18	± 0.14	kJ/mol	26.0367 ± 0.0016	25641-79-6*0
Bromide			-120.80	± 0.16	kJ/mol	79.90455 ± 0.00100	24959-67-9*800
1-Ethylium-1-ylidene		1329.6	1328.2	± 1.2	kJ/mol	27.0447 ± 0.0016	78949-84-5*0
Ethylidyne anion		456.8	452.7	± 1.4	kJ/mol	27.0458 ± 0.0016	117768-70-4*0
Vinylidene anion		364.15	363.97	± 0.62	kJ/mol	26.0378 ± 0.0016	66295-36-1*0
Iodide			-56.829	± 0.090	kJ/mol	126.905019 ± 0.000030	20461-54-5*800
Ethynylium		1687.59	1690.93	± 0.16	kJ/mol	25.0288 ± 0.0016	16456-59-0*0
Aminomethyl		159.40	148.51	± 0.58	kJ/mol	30.04920 ± 0.00085	10507-29-6*0
Methylamidogen anion		145.99	134.64	± 0.76	kJ/mol	30.04975 ± 0.00085	54448-39-4*0
Methyleneamidogen		242.22	238.56	± 0.85	kJ/mol	28.03332 ± 0.00082	15845-29-1*0
(Z)-Iminomethyl		294.5	291.0	± 1.2	kJ/mol	28.03332 ± 0.00082	54980-11-9*0
Methyloxoniumylidene		1062.43	1054.62	± 0.72	kJ/mol	31.03337 ± 0.00088	58157-09-8*0
Hydroxymethylene		130.86	127.11	± 0.34	kJ/mol	30.02598 ± 0.00087	19710-56-6*2
Hydroxymethylene cation		971.9	968.3	± 1.3	kJ/mol	30.02543 ± 0.00087	135395-06-1*1
Hydrogen difluoride cation		1173.5	1170.6	± 1.7	kJ/mol	39.004198 ± 0.000070	126950-54-70
Oxoniumyl ion		978.472	975.569	± 0.029	kJ/mol	18.01473 ± 0.00033	56583-62-1*0
Isoformyl		217.30	217.69	± 0.67	kJ/mol	29.01804 ± 0.00086	71080-92-7*0
Azide ion		193.63	190.05	± 0.89	kJ/mol	42.02077 ± 0.00021	14343-69-2*0
1-Propenyl		280.02	269.21	± 0.81	kJ/mol	41.0718 ± 0.0024	6067-68-1*1
Cyclopropene		292.54	283.82	± 0.54	kJ/mol	40.0639 ± 0.0024	2781-85-3*0
Cyclobutane		52.17	27.63	± 0.47	kJ/mol	56.1063 ± 0.0032	287-23-0*0
Dioxidenium		1110.87	1107.98	± 0.11	kJ/mol	33.00619 ± 0.00060	12207-52-2*0
n-Heptane		-145.65	-187.53	± 0.48	kJ/mol	100.2019 ± 0.0057	142-82-5*0
n-Octane		-161.43	-208.27	± 0.67	kJ/mol	114.2285 ± 0.0065	111-65-9*0
1-Hydroxyethylium		611.1	596.6	± 1.2	kJ/mol	45.0600 ± 0.0017	18682-96-7*2
1H-Triazirin-1-yl		585.9	584.1	± 2.0	kJ/mol	42.02022 ± 0.00021	912535-95-6*0
Vinyl alcohol		-108.10	-118.62	± 0.88	kJ/mol	44.0526 ± 0.0017	557-75-5*2
Vinyl alcohol cation		779.2	768.0	± 1.2	kJ/mol	44.0520 ± 0.0017	57239-63-1*2
Oxiranyl		172.8	164.5	± 1.4	kJ/mol	43.0446 ± 0.0016	31586-84-2*0
Oxiranylium		901.6	893.6	± 1.4	kJ/mol	43.0441 ± 0.0016	57789-76-1*2
C=O=C		653.3	657.6	± 2.2	kJ/mol	40.0208 ± 0.0016	12071-23-71
C=O=C		721.5	725.9	± 1.6	kJ/mol	40.0208 ± 0.0016	12071-23-72
Oxirene		272.81	272.12	± 0.98	kJ/mol	42.0367 ± 0.0016	157-18-6*2
Oxirene		388.7	384.5	± 2.6	kJ/mol	42.0367 ± 0.0016	157-18-6*11
Formic acid cation		721.86	714.77	± 0.26	kJ/mol	46.0248 ± 0.0010	50614-05-6*1
Dioxirane		9.41	1.74	± 0.54	kJ/mol	46.0254 ± 0.0010	157-26-6*0
Formyloxidanyl		-120.94	-124.29	± 0.55	kJ/mol	45.0174 ± 0.0010	16499-21-1*2
Isofulminic acid		170.91	169.45	± 0.49	kJ/mol	43.02478 ± 0.00086	51060-05-0*0
Trioxidanylium		1070.2	1063.9	± 1.3	kJ/mol	49.00559 ± 0.00090	74241-49-9*1
Methyl formate		-324.6	-337.1	± 1.6	kJ/mol	60.0520 ± 0.0017	107-31-3*2
Methyl iodide			-12.20	± 0.19	kJ/mol	141.93899 ± 0.00083	74-88-4*590
Difluoromethylene		43.20	43.92	± 0.38	kJ/mol	50.00751 ± 0.00080	2154-59-8*1
Difluoromethylene		-193.99	-193.51	± 0.38	kJ/mol	50.00751 ± 0.00080	2154-59-8*2
Ethyl iodide		-9.40	-39.26	± 0.49	kJ/mol	155.9656 ± 0.0016	75-03-6*500
Fluoro(fluorooxy)methylene		-135.8	-137.0	± 2.0	kJ/mol	66.00691 ± 0.00085	479587-30-9*2
Dibromophosgene		-97.98	-113.91	± 0.37	kJ/mol	187.8181 ± 0.0022	593-95-3*0
Fluoride			-334.51	± 0.17	kJ/mol	18.99895178 ± 0.00000050	16984-48-8*800
Benzene		50.72	49.17	± 0.25	kJ/mol	78.1118 ± 0.0048	71-43-2*500
Benzoyl fluoride		-288.0	-304.4	± 1.5	kJ/mol	124.1124 ± 0.0056	455-32-3*0
(E)-Diazene cation		1132.58	1125.67	± 0.67	kJ/mol	30.02881 ± 0.00020	59952-06-6*0
(E)-Diazene anion		269.3	262.4	± 1.7	kJ/mol	30.02991 ± 0.00020	59952-06-60
(Z)-Diazene	$[H]/N=N\[H]$	229.21	222.07	± 0.64	kJ/mol	30.02936 ± 0.00020	15626-42-3*0
Diazenyl		252.25	249.33	± 0.48	kJ/mol	29.02142 ± 0.00016	36882-13-0*0
Hydroxyaminiumyl		1160.6	1157.7	± 1.3	kJ/mol	31.01353 ± 0.00032	63559-88-6*0
Hydroxyamidogen		123.5	117.0	± 1.4	kJ/mol	32.02202 ± 0.00034	13940-32-4*2
Hydroxyaminylium		1020.2	1013.0	± 1.9	kJ/mol	32.02147 ± 0.00034	66097-71-0*1
Triiodide ion			-51.36	± 0.80	kJ/mol	380.713959 ± 0.000090	14900-04-0*800
Dioxyamidogen		240.4	233.7	± 1.8	kJ/mol	47.01348 ± 0.00061	71843-95-3*2
Peroxynitrous acid		-0.35	-7.40	± 0.53	kJ/mol	63.01288 ± 0.00091	14691-52-2*2
Dioxiranylidene		190.6	191.4	± 1.3	kJ/mol	44.00950 ± 0.00100	138832-57-2*0
Deuterium atom		219.804	221.717	± 0.000	kJ/mol	2.01410177800 ± 0.00000000040	16873-17-9*0
Hypoiodite		-102.5	-104.4	± 1.2	kJ/mol	142.90442 ± 0.00030	15065-65-3*0
Methylene anion		328.48	328.91	± 0.51	kJ/mol	14.02713 ± 0.00081	50928-07-9*0
Methylidyne		592.78	596.12	± 0.11	kJ/mol	13.01864 ± 0.00080	3315-37-5*1
Hydrogen fluoride			-321.15	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*821
Ethylidyne		508.58	504.88	± 0.87	kJ/mol	27.0452 ± 0.0016	67624-57-1*1
Trioxodinitrate anion		-104.4	-108.4	± 2.3	kJ/mol	76.01223 ± 0.00091	194856-62-7*100
Aminomethylium		763.9	752.0	± 1.8	kJ/mol	30.04865 ± 0.00085	488821-23-4*0
Methylamidogen		187.86	177.13	± 0.61	kJ/mol	30.04920 ± 0.00085	15622-51-2*0
Aminomethylene		246.6	238.8	± 1.6	kJ/mol	29.04126 ± 0.00083	35430-17-2*0
Methylimidogen		323.8	316.0	± 1.6	kJ/mol	29.04126 ± 0.00083	27770-42-9*0
Methyleneamidogen anion		193.1	189.3	± 1.1	kJ/mol	28.03387 ± 0.00082	28892-56-0*0
Aminomethylidyne		372.2	368.7	± 1.4	kJ/mol	28.03332 ± 0.00082	84654-89-7*0
Hydrogen isocyanide		191.79	192.18	± 0.47	kJ/mol	27.02538 ± 0.00081	6914-07-4*0
Cyanide		63.958	67.244	± 0.095	kJ/mol	26.01799 ± 0.00080	57-12-5*0
Methyleneoxonium		154.6	146.3	± 1.4	kJ/mol	32.04186 ± 0.00090	177788-17-9*0
Hydroxymethylene		219.0	216.1	± 1.1	kJ/mol	30.02598 ± 0.00087	19710-56-6*3
Hydroxymethylene anion		147.4	144.4	± 1.4	kJ/mol	30.02653 ± 0.00087	207914-87-2*1
Dinitrogen tetraoxide		20.15	10.86	± 0.14	kJ/mol	92.0111 ± 0.0012	10544-72-6*0
Hydroxymethyliumylidene		986.13	987.77	± 0.80	kJ/mol	29.01749 ± 0.00086	60528-75-8*0
Isoformyl anion		55.8	58.4	± 1.8	kJ/mol	29.01859 ± 0.00086	81747-63-9*1
Propylium		856.87	838.65	± 0.83	kJ/mol	43.0871 ± 0.0024	19252-52-9*0
Cyclopropyl		302.8	290.2	± 1.6	kJ/mol	41.0718 ± 0.0024	2417-82-5*0
Cycloprop-1-enyl		528.11	523.53	± 0.78	kJ/mol	39.0559 ± 0.0024	19528-44-0*0
Cycloprop-2-enyl		491.03	486.42	± 0.77	kJ/mol	39.0559 ± 0.0024	28933-84-8*0
Cyclopropenylidene		497.07	496.12	± 0.47	kJ/mol	38.0480 ± 0.0024	16165-40-5*0
2-Propynylidyne anion		539.97	544.82	± 0.84	kJ/mol	37.0406 ± 0.0024	82893-67-2*0
Cyclopropynyl		710.7	714.8	± 1.1	kJ/mol	37.0400 ± 0.0024	119178-99-3*0
n-Butyl		101.48	78.25	± 0.98	kJ/mol	57.1143 ± 0.0033	2492-36-6*0
Methylcyclopropane		47.5	24.3	± 1.3	kJ/mol	56.1063 ± 0.0032	594-11-6*0
Cyclobutene		176.79	159.74	± 0.93	kJ/mol	54.0904 ± 0.0032	822-35-5*0
Oxygen cation monohydrate		1153.2	1147.7	± 3.3	kJ/mol	34.01413 ± 0.00062	31748-17-10
Oxygen anion monohydrate		-239.1	-244.3	± 3.0	kJ/mol	34.01523 ± 0.00062	31748-17-1*0
Vinyl alcohol cation		787.30	776.18	± 0.99	kJ/mol	44.0520 ± 0.0017	57239-63-1*1
Vinoxy cation		1020.2	1013.2	± 1.6	kJ/mol	43.0441 ± 0.0016	35731-40-91
Vinoxide		-153.55	-160.60	± 0.77	kJ/mol	43.0452 ± 0.0016	35731-40-9*0
Acetic acid			-485.18	± 0.23	kJ/mol	60.0520 ± 0.0017	64-19-7*800
Ketene		-45.45	-48.57	± 0.13	kJ/mol	42.0367 ± 0.0016	463-51-4*2
COC vdW		589.8	598.5	± 1.8	kJ/mol	40.0208 ± 0.0016	12071-24-81
Oxirene		390.8	386.6	± 2.7	kJ/mol	42.0367 ± 0.0016	157-18-6*12
Methylperoxy anion		-89.79	-99.94	± 0.67	kJ/mol	47.0339 ± 0.0010	35683-44-4*0
Formyloxoniumylidene		1016.9	1013.5	± 1.3	kJ/mol	45.0169 ± 0.0010	54375-27-8*0
Dioxymethylene		363.6	361.2	± 2.6	kJ/mol	45.0174 ± 0.0010	438586-67-5*1
Trioxidaniumyl		927.1	917.8	± 1.3	kJ/mol	50.01353 ± 0.00091	161321-37-5*2
Cyanic acid		-12.21	-14.92	± 0.49	kJ/mol	43.02478 ± 0.00086	420-05-3*0
Fulminic acid		235.37	233.67	± 0.48	kJ/mol	43.02478 ± 0.00086	506-85-4*0
Isocyanate		-221.11	-221.33	± 0.54	kJ/mol	42.01739 ± 0.00086	71000-82-3*0
Nitrosomethylidyne		389.4	390.7	± 1.5	kJ/mol	42.01684 ± 0.00086	82267-15-0*0
Oxazirinyl		449.9	450.7	± 1.5	kJ/mol	42.01684 ± 0.00086	228850-18-8*0
Dimethylamine		5.91	-15.99	± 0.67	kJ/mol	45.0837 ± 0.0017	124-40-3*0
Trimethylamine		4.47	-24.08	± 0.63	kJ/mol	59.1103 ± 0.0025	75-50-3*0
Isocyanogen		410.7	413.1	± 1.6	kJ/mol	52.0349 ± 0.0016	83951-85-3*0
Diisocyanogen		610.1	613.0	± 1.7	kJ/mol	52.0349 ± 0.0016	78800-21-2*0
Fluorosyl ion		1342.62	1342.57	± 0.78	kJ/mol	34.99725 ± 0.00030	12763-67-6*0
Cyanoamidogen		324.7	322.3	± 1.7	kJ/mol	41.03212 ± 0.00082	12347-01-2*0
Oxywater		65.0	58.5	± 1.2	kJ/mol	34.01468 ± 0.00062	171363-09-0*0
Bromodichloromethane		-38.6	-50.3	± 1.3	kJ/mol	163.8280 ± 0.0022	75-27-4*0
Chlorous acid		25.67	20.61	± 0.67	kJ/mol	68.4594 ± 0.0011	13898-47-0*0
Difluorodibromomethane		-366.7	-384.4	± 1.4	kJ/mol	209.8155 ± 0.0022	75-61-6*0
Dichlorodibromomethane		19.6	3.9	± 1.5	kJ/mol	242.7241 ± 0.0028	594-18-3*0
Bromodifluoromethane		-410.92	-424.11	± 0.49	kJ/mol	130.9194 ± 0.0013	1511-62-2*0
1,2-Difluoroethane		-434.51	-447.94	± 0.86	kJ/mol	66.0500 ± 0.0016	624-72-6*0
2-Hydrotrioxy anion		27.6	21.9	± 1.2	kJ/mol	49.00669 ± 0.00090	89965-38-80
1,2-Difluoroacetylene		2.45	5.27	± 0.65	kJ/mol	62.0182 ± 0.0016	689-99-6*0
Fluoro(fluorooxy)methylene		-38.9	-40.4	± 1.9	kJ/mol	66.00691 ± 0.00085	479587-30-9*1
Chloroformyl		-21.93	-20.54	± 0.49	kJ/mol	63.4628 ± 0.0012	2602-42-8*0
Phenylium		1251.6	1239.4	± 3.3	kJ/mol	77.1034 ± 0.0048	17333-73-2*1
Chlorobenzene cation		942.47	928.55	± 0.61	kJ/mol	112.5561 ± 0.0049	55450-32-3*0
Chlorobenzene			11.22	± 0.59	kJ/mol	112.5566 ± 0.0049	108-90-7*500
Bromobenzene cation		994.7	973.3	± 1.3	kJ/mol	157.0074 ± 0.0049	55450-33-4*0
Iodobenzene		112.7	112.8	± 1.1	kJ/mol	204.0084 ± 0.0048	591-50-4*500
2-Hydrotrioxy cation		1297.8	1291.1	± 1.3	kJ/mol	49.00559 ± 0.00090	74241-49-90
Methyl nitrite		-55.46	-66.13	± 0.46	kJ/mol	61.0401 ± 0.0010	624-91-9*0
1,2-Dichloroethane		-118.24	-130.18	± 0.59	kJ/mol	98.9586 ± 0.0024	107-06-2*0
Carbon atom anion		589.624	594.771	± 0.050	kJ/mol	12.01125 ± 0.00080	14337-00-9*0
Chloride			-166.994	± 0.023	kJ/mol	35.45325 ± 0.00090	16887-00-6*800
Dioxymethylidyne		298.6	299.9	± 1.5	kJ/mol	44.00950 ± 0.00100	791121-04-5*0
Oxadiazirine		352.1	350.3	± 1.4	kJ/mol	44.01288 ± 0.00033	227934-45-4*0
2-Cyclopropyn-1-ylidene		899.2	906.1	± 1.5	kJ/mol	36.0321 ± 0.0024	102508-15-6*1
Propynylidyne cation		1948.3	1956.2	± 2.0	kJ/mol	36.0316 ± 0.0024	154702-35-9*0
Ethylene cation		1075.28	1068.07	± 0.13	kJ/mol	28.0526 ± 0.0016	34470-02-5*0
Bifluoride		-709.1	-713.0	± 1.8	kJ/mol	39.005295 ± 0.000070	18130-74-0*0
NON		544.7	541.5	± 1.5	kJ/mol	44.01288 ± 0.00033	227934-46-5*0
Iminomethyl anion		238.9	235.1	± 1.9	kJ/mol	28.03387 ± 0.00082	90623-30-6*1
Isoformyl anion		267.4	268.0	± 1.6	kJ/mol	29.01859 ± 0.00086	81747-63-9*2
2-Propynylium		1193.47	1190.66	± 0.38	kJ/mol	39.0554 ± 0.0024	21540-27-2*0
2-Cyclopropen-1-ylium-1-yl		1382.0	1381.0	± 1.2	kJ/mol	38.0474 ± 0.0024	85398-75-0*0
Propynylidene		597.6	599.3	± 1.2	kJ/mol	38.0480 ± 0.0024	67152-18-5*3
Propenediylidene		796.2	797.4	± 1.3	kJ/mol	38.0480 ± 0.0024	60731-11-5*0
Dioxygen anion		-43.38	-42.74	± 0.17	kJ/mol	31.99935 ± 0.00060	11062-77-4*0
Trifluoromethide		-637.7	-639.6	± 1.6	kJ/mol	69.00646 ± 0.00080	54128-17-5*0
Hydrogen fluoride			-321.07	± 0.17	kJ/mol	20.006343 ± 0.000070	7664-39-3*902
Cyclopentene		58.12	33.85	± 0.45	kJ/mol	68.1170 ± 0.0040	142-29-0*0
Ethyloxoniumyl		784.1	766.9	± 1.5	kJ/mol	46.0679 ± 0.0017	34480-55-2*0
1-Hydroxyethylium		609.14	594.72	± 0.39	kJ/mol	45.0600 ± 0.0017	18682-96-7*0
Acetaldehyde cation		832.02	822.04	± 0.29	kJ/mol	44.0520 ± 0.0017	36505-03-0*0
Oxiranylium		1233.7	1226.7	± 1.8	kJ/mol	43.0441 ± 0.0016	57789-76-1*1
Oxiranyl anion		121.4	113.3	± 1.6	kJ/mol	43.0452 ± 0.0016	72722-59-9*0
Dibromine monoxide		120.9	104.4	± 1.3	kJ/mol	175.8074 ± 0.0020	21308-80-5*0
Fluorochlorate		-255.99	-255.39	± 0.80	kJ/mol	54.45165 ± 0.00090	12272-56-9*0
Ethynol anion		-48.62	-47.37	± 0.87	kJ/mol	41.0293 ± 0.0016	64066-01-9*0
Dicarbon monoxide anion		153.8	157.5	± 1.2	kJ/mol	40.0213 ± 0.0016	87191-88-6*0
Dicarbon monoxide cation		1433.5	1438.5	± 1.8	kJ/mol	40.0203 ± 0.0016	12287-08-0*0
Hydroxyimidogen		217.45	214.57	± 0.87	kJ/mol	31.01408 ± 0.00032	35337-59-8*0
COC vdW		727.2	735.5	± 1.7	kJ/mol	40.0208 ± 0.0016	12071-24-82
C=O-C cation		1576.2	1583.3	± 2.3	kJ/mol	40.0203 ± 0.0016	83483-98-1*1
C=O=C anion		551.0	554.7	± 2.1	kJ/mol	40.0213 ± 0.0016	87191-88-60
Aminylium		1266.55	1264.47	± 0.12	kJ/mol	16.02207 ± 0.00016	15194-15-7*0
Formic acid cation		723.8	716.7	± 1.1	kJ/mol	46.0248 ± 0.0010	50614-05-6*2
Formic acid anion		-255.6	-261.8	± 1.7	kJ/mol	46.0259 ± 0.0010	19066-82-1*1
Nitrous acid		-71.37	-77.72	± 0.29	kJ/mol	47.01348 ± 0.00061	7782-77-6*2
Peroxyhypochlorous acid		3.86	-1.42	± 0.99	kJ/mol	68.4594 ± 0.0011	67952-07-2*0
OH-CO vdW complex		-80.30	-77.41	± 0.96	kJ/mol	45.0174 ± 0.0010	2564-85-4100
CO-HO vdW complex		-77.6	-73.6	± 1.8	kJ/mol	45.0174 ± 0.0010	2564-84-3100
H-CO2 vdW complex		-179.3	-178.3	± 2.2	kJ/mol	45.0174 ± 0.0010	2564-83-2100
Azidonitrene		692.0	687.4	± 1.4	kJ/mol	56.02696 ± 0.00028	147363-92-6*2
Isocyanic acid cation		1003.03	1000.37	± 0.51	kJ/mol	43.02423 ± 0.00086	444010-28-0*0
Isofulminic acid cation		1215.8	1213.0	± 1.3	kJ/mol	43.02423 ± 0.00086	114766-65-3*0
Acetic acid			-484.91	± 0.23	kJ/mol	60.0520 ± 0.0017	64-19-7*840
Acetyl chloride			-272.21	± 0.33	kJ/mol	78.4973 ± 0.0019	75-36-5*500
Chlorosyl ion		1150.69	1150.53	± 0.66	kJ/mol	51.45155 ± 0.00095	12301-79-0*0
(Formyloxy)methyl		-148.7	-156.8	± 1.5	kJ/mol	59.0440 ± 0.0017	3122-12-1*1
Glyoxal		-206.99	-212.63	± 0.52	kJ/mol	58.0361 ± 0.0017	107-22-2*1
Diazoethenylidene		657.0	659.6	± 3.0	kJ/mol	52.0349 ± 0.0016	130760-10-0*0
Isocyanomethylidyne		671.3	675.7	± 3.6	kJ/mol	38.0281 ± 0.0016	53590-27-5*0
Diazomethyl		472.8	470.2	± 2.0	kJ/mol	41.03212 ± 0.00082	20813-32-5*0
Isocyanoamidogen		492.7	490.7	± 2.0	kJ/mol	41.03212 ± 0.00082	947408-73-3*0
Tetrachloromethane		-109.53	-128.94	± 0.65	kJ/mol	153.8215 ± 0.0037	56-23-5*500
Dioxygenyl ion monohydrate		828.6	821.5	± 1.9	kJ/mol	50.01353 ± 0.00091	11083-61-7*0
Chloroform			-133.87	± 0.63	kJ/mol	119.3767 ± 0.0028	67-66-3*590