Selected ATcT [1, 2] enthalpy of formation based on version 1.172 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.156 to include species relevant to a study of photodissociation of formamide[4].

Cycloheptane

Formula: CH2(CH2CH2CH2CH2CH2CH2) (g)

CAS RN: 291-64-5

ATcT ID: 291-64-5*0

SMILES: C1CCCCCC1

InChI: InChI=1S/C7H14/c1-2-4-6-7-5-3-1/h1-7H2

InChIKey: DMEGYFMYUHOHGS-UHFFFAOYSA-N

Hills Formula: C7H14

2D Image:

Aliases: CH2(CH2CH2CH2CH2CH2CH2); Cycloheptane; Suberane; cyc-C7H14; UN 2241; NSC 5164

Relative Molecular Mass: 98.1861 ± 0.0057

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
-72.42	-117.92	± 0.52	kJ/mol

3D Image of CH2(CH2CH2CH2CH2CH2CH2) (g)

spin ON spin OFF

Top contributors to the provenance of Δ_fH° of CH2(CH2CH2CH2CH2CH2CH2) (g)

The 20 contributors listed below account only for 88.5% of the provenance of Δ_fH° of CH2(CH2CH2CH2CH2CH2CH2) (g).
A total of 24 contributors would be needed to account for 90% of the provenance.

Please note: The list is limited to 20 most important contributors or, if less, a number sufficient to account for 90% of the provenance. The Reference acts as a further link to the relevant references and notes for the measurement. The Measured Quantity is normaly given in the original units; in cases where we have reinterpreted the original measurement, the listed value may differ from that given by the authors. The quoted uncertainty is the a priori uncertainty used as input when constructing the initial Thermochemical Network, and corresponds either to the value proposed by the original authors or to our estimate; if an additional multiplier is given in parentheses immediately after the prior uncertainty, it corresponds to the factor by which the prior uncertainty needed to be multiplied during the ATcT analysis in order to make that particular measurement consistent with the prevailing knowledge contained in the Thermochemical Network.

Contribution (%)	TN ID	Reaction	Measured Quantity	Reference
47.9	7008.2	CH2(CH2CH2CH2CH2CH2CH2) (cr,l) + 21/2 O2 (g) → 7 CO2 (g) + 7 H2O (cr,l)	Δ_rH°(298.15 K) = -1099.09 ± 0.14 kcal/mol	Kaarsemaker 1952, as quoted by Cox 1970
7.1	7009.2	CH2(CH2CH2CH2CH2CH2CH2) (cr,l) → CH2(CH2CH2CH2CH2CH2CH2) (g)	Δ_rH°(298.15 K) = 9.21 ± 0.05 kcal/mol	Finke 1956
7.0	7008.3	CH2(CH2CH2CH2CH2CH2CH2) (cr,l) + 21/2 O2 (g) → 7 CO2 (g) + 7 H2O (cr,l)	Δ_rH°(298.15 K) = -4597.0 ± 0.8 (×1.915) kJ/mol	Kozina 1961, as quoted by NIST WebBook
5.8	7008.1	CH2(CH2CH2CH2CH2CH2CH2) (cr,l) + 21/2 O2 (g) → 7 CO2 (g) + 7 H2O (cr,l)	Δ_rH°(298.15 K) = -1099.08 ± 0.40 kcal/mol	Spitzer 1947
3.9	7026.1	CH2(CHCHCHCHCHCH) (g) + 3 H2 (g) → CH2(CH2CH2CH2CH2CH2CH2) (g)	Δ_rH°(355.15 K) = -72.862 ± 0.300 kcal/mol	Conn 1939
2.1	125.2	1/2 O2 (g) + H2 (g) → H2O (cr,l)	Δ_rH°(298.15 K) = -285.8261 ± 0.040 kJ/mol	Rossini 1939, Rossini 1931, Rossini 1931b, note H2Oa, Rossini 1930
1.3	7007.5	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.69 ± 0.85 kcal/mol	Ruscic W1RO
1.2	7009.1	CH2(CH2CH2CH2CH2CH2CH2) (cr,l) → CH2(CH2CH2CH2CH2CH2CH2) (g)	Δ_rH°(298.15 K) = 38.5 ± 0.5 kJ/mol	Anand 1975, as quoted by NIST WebBook, est unc
1.1	7007.2	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.03 ± 0.90 kcal/mol	Ruscic G4
1.1	7007.4	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.22 ± 0.90 kcal/mol	Ruscic CBS-n
1.1	7007.1	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.05 ± 0.90 kcal/mol	Ruscic G3X
1.0	2375.1	2 H2 (g) + C (graphite) → CH4 (g)	Δ_rG°(1165 K) = 37.521 ± 0.068 kJ/mol	Smith 1946, note COf, 3rd Law
1.0	7012.5	CH2(CHCHCH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CHCHCH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.05 ± 0.85 kcal/mol	Ruscic W1RO
0.9	2228.7	C (graphite) + O2 (g) → CO2 (g)	Δ_rH°(298.15 K) = -393.464 ± 0.024 kJ/mol	Hawtin 1966, note CO2e
0.9	7007.3	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.28 ± 1.0 kcal/mol	Ruscic CBS-n
0.9	7012.2	CH2(CHCHCH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CHCHCH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = 0.85 ± 0.90 kcal/mol	Ruscic G4
0.9	7012.4	CH2(CHCHCH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CHCHCH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = 0.80 ± 0.90 kcal/mol	Ruscic CBS-n
0.9	7012.1	CH2(CHCHCH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CHCHCH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = 0.77 ± 0.90 kcal/mol	Ruscic G3X
0.8	2373.7	CH4 (g) + 2 O2 (g) → CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -890.578 ± 0.078 kJ/mol	Schley 2010
0.7	7012.3	CH2(CHCHCH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CHCHCH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = 0.59 ± 1.0 kcal/mol	Ruscic CBS-n

Top 10 species with enthalpies of formation correlated to the Δ_fH° of CH2(CH2CH2CH2CH2CH2CH2) (g)

Please note: The correlation coefficients are obtained by renormalizing the off-diagonal elements of the covariance matrix by the corresponding variances.
The correlation coefficient is a number from -1 to 1, with 1 representing perfectly correlated species, -1 representing perfectly anti-correlated species, and 0 representing perfectly uncorrelated species.

Correlation Coefficent (%)	Species Name	Formula	Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units	Relative Molecular Mass	ATcT ID
93.0	Cycloheptane	CH2(CH2CH2CH2CH2CH2CH2) (cr,l)	-126.57	-156.46	± 0.50	kJ/mol	98.1861 ± 0.0057	291-64-5*500
66.7	1,3-Cycloheptadiene	CH2(CHCHCHCHCH2CH2) (g, c-c)	123.65	94.54	± 0.78	kJ/mol	94.1543 ± 0.0056	4054-38-0*1
64.0	Cycloheptene	CH2(CHCHCH2CH2CH2CH2) (g)	28.55	-8.68	± 0.74	kJ/mol	96.1702 ± 0.0057	628-92-2*0
30.3	Carbonic acid	C(O)(OH)2 (aq, undissoc)		-698.673	± 0.028	kJ/mol	62.0248 ± 0.0012	463-79-6*1000
30.2	Cycloheptatriene	CH2(CHCHCHCHCHCH) (g)	207.79	184.37	± 0.90	kJ/mol	92.1384 ± 0.0056	544-25-2*0
29.4	Cycloheptatriene	CH2(CHCHCHCHCHCH) (cr,l)	154.44	145.65	± 0.92	kJ/mol	92.1384 ± 0.0056	544-25-2*500
29.2	Cycloheptene	CH2(CHCHCH2CH2CH2CH2) (cr,l)	-25.1	-46.2	± 1.7	kJ/mol	96.1702 ± 0.0057	628-92-2*500
26.9	Water	H2O (cr,l)	-286.276	-285.804	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*500
26.9	Water	H2O (l)		-285.804	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*590
26.9	Oxonium	[H3O]+ (aq)		-285.804	± 0.022	kJ/mol	19.02267 ± 0.00037	13968-08-6*800

Most Influential reactions involving CH2(CH2CH2CH2CH2CH2CH2) (g)

Please note: The list, which is based on a hat (projection) matrix analysis, is limited to no more than 20 largest influences.

Influence Coefficient	TN ID	Reaction	Measured Quantity	Reference
0.839	7021.1	CH2(CHCHCHCHCH2CH2) (g, c-c) + 2 H2 (g) → CH2(CH2CH2CH2CH2CH2CH2) (g)	Δ_rH°(355.15 K) = -51.271 ± 0.150 kcal/mol	Conn 1939
0.828	7009.2	CH2(CH2CH2CH2CH2CH2CH2) (cr,l) → CH2(CH2CH2CH2CH2CH2CH2) (g)	Δ_rH°(298.15 K) = 9.21 ± 0.05 kcal/mol	Finke 1956
0.824	7011.1	CH2(CHCHCH2CH2CH2CH2) (g) + H2 (g) → CH2(CH2CH2CH2CH2CH2CH2) (g)	Δ_rH°(355.15 K) = -26.521 ± 0.150 kcal/mol	Conn 1939
0.501	7026.1	CH2(CHCHCHCHCHCH) (g) + 3 H2 (g) → CH2(CH2CH2CH2CH2CH2CH2) (g)	Δ_rH°(355.15 K) = -72.862 ± 0.300 kcal/mol	Conn 1939
0.145	7009.1	CH2(CH2CH2CH2CH2CH2CH2) (cr,l) → CH2(CH2CH2CH2CH2CH2CH2) (g)	Δ_rH°(298.15 K) = 38.5 ± 0.5 kJ/mol	Anand 1975, as quoted by NIST WebBook, est unc
0.026	7019.5	CH2(CHCHCHCHCH2CH2) (g, c-c) + CH3CH2CH2CH3 (g) → CH2(CH2CH2CH2CH2CH2CH2) (g) + CH2CHCHCH2 (g)	Δ_rH°(0 K) = 6.38 ± 0.9 kcal/mol	Ruscic W1RO
0.026	7007.5	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.69 ± 0.85 kcal/mol	Ruscic W1RO
0.023	7007.1	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.05 ± 0.90 kcal/mol	Ruscic G3X
0.023	7007.4	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.22 ± 0.90 kcal/mol	Ruscic CBS-n
0.023	7007.2	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.03 ± 0.90 kcal/mol	Ruscic G4
0.021	7019.2	CH2(CHCHCHCHCH2CH2) (g, c-c) + CH3CH2CH2CH3 (g) → CH2(CH2CH2CH2CH2CH2CH2) (g) + CH2CHCHCH2 (g)	Δ_rH°(0 K) = 6.04 ± 1.0 kcal/mol	Ruscic G4
0.021	7019.4	CH2(CHCHCHCHCH2CH2) (g, c-c) + CH3CH2CH2CH3 (g) → CH2(CH2CH2CH2CH2CH2CH2) (g) + CH2CHCHCH2 (g)	Δ_rH°(0 K) = 6.43 ± 1.0 kcal/mol	Ruscic CBS-n
0.019	7007.3	CH2(CH2CH2CH2CH2CH2CH2) (g) + CH3CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH3 (g)	Δ_rH°(0 K) = -0.28 ± 1.0 kcal/mol	Ruscic CBS-n
0.017	7019.1	CH2(CHCHCHCHCH2CH2) (g, c-c) + CH3CH2CH2CH3 (g) → CH2(CH2CH2CH2CH2CH2CH2) (g) + CH2CHCHCH2 (g)	Δ_rH°(0 K) = 6.13 ± 1.1 kcal/mol	Ruscic G3X
0.012	7019.3	CH2(CHCHCHCHCH2CH2) (g, c-c) + CH3CH2CH2CH3 (g) → CH2(CH2CH2CH2CH2CH2CH2) (g) + CH2CHCHCH2 (g)	Δ_rH°(0 K) = 6.31 ± 1.3 kcal/mol	Ruscic CBS-n

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 and D. H. Bross, Active Thermochemical Tables (ATcT) values based on ver. 1.172 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		K. L. Caster, N. A. Seifert, B. Ruscic, A. W. Jasper, and K. Prozument, Dynamics of HCN, NHC, and HNCO Formation in the 193 nm Photodissociation of Formamide J. Phys. Chem. A (in press) (2024) [DOI: 10.1021/acs.jpca.4c02232]
5		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]
6		B. Ruscic and D. H. Bross, Thermochemistry Computer Aided Chem. Eng. 45, 3-114 (2019) [DOI: 10.1016/B978-0-444-64087-1.00001-2]

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 [5] and Ruscic and Bross[6]).
Note that an uncertainty of ± 0.000 kJ/mol indicates that the estimated uncertainty is < ± 0.000₅ kJ/mol.

Website Functionality Credits

The reorganization of the website was developed and implemented by David H. Bross (ANL).
The find function is based on the complete Species Dictionary entries for the appropriate version of the ATcT TN.
The molecule images are rendered by Indigo-depict.
The XYZ renderings are based on Jmol: an open-source Java viewer for chemical structures in 3D. http://www.jmol.org/.

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.