Selected ATcT [1, 2] enthalpy of formation based on version 1.176 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.172 to include species related to Criegee intermediates that are involved in several ongoing studies[4].

Cyclopentane

Formula: CH2(CH2CH2CH2CH2) (l)

CAS RN: 287-92-3

ATcT ID: 287-92-3*590

SMILES: C1CCCC1

InChI: InChI=1S/C5H10/c1-2-4-5-3-1/h1-5H2

InChIKey: RGSFGYAAUTVSQA-UHFFFAOYSA-N

Hills Formula: C5H10

2D Image:

Aliases: CH2(CH2CH2CH2CH2); Cyclopentane; cyc-C5H10; Pentamethylene; Exxsol HP 95; H&N; Marukazol FH; NSC 60213; Zeonsolv HP; UN 1146

Relative Molecular Mass: 70.1329 ± 0.0041

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
	-104.65	± 0.38	kJ/mol

Top contributors to the provenance of Δ_fH° of CH2(CH2CH2CH2CH2) (l)

The 20 contributors listed below account only for 70.8% of the provenance of Δ_fH° of CH2(CH2CH2CH2CH2) (l).
A total of 109 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
32.5	3959.4	CH2(CH2CH2CH2CH2) (l) + 15/2 O2 (g) → 5 CO2 (g) + 5 H2O (l)	Δ_rH°(298.15 K) = -786.84 ± 0.14 kcal/mol	Kaarsemaker 1952, as quoted by Cox 1970
13.3	3959.1	CH2(CH2CH2CH2CH2) (l) + 15/2 O2 (g) → 5 CO2 (g) + 5 H2O (l)	Δ_rH°(298.15 K) = -3290.85 ± 0.72 (×1.269) kJ/mol	Johnson 1946
7.0	3959.3	CH2(CH2CH2CH2CH2) (l) + 15/2 O2 (g) → 5 CO2 (g) + 5 H2O (l)	Δ_rH°(298.15 K) = -786.61 ± 0.30 kcal/mol	Spitzer 1947
4.0	3969.1	CH2(CHCHCHCH) (g) + 2 H2 (g) → CH2(CH2CH2CH2CH2) (g)	Δ_rH°(355.15 K) = -50.907 ± 0.200 kcal/mol	Kistiakowsky 1936
1.8	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
1.2	3964.2	CH2(CH2CHCHCH2) (l) + 7 O2 (g) → 5 CO2 (g) + 4 H2O (l)	Δ_rH°(298.15 K) = -744.54 ± 0.14 (×4.861) kcal/mol	Labbauf 1961
1.1	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
0.9	3964.1	CH2(CH2CHCHCH2) (l) + 7 O2 (g) → 5 CO2 (g) + 4 H2O (l)	Δ_rH°(298.15 K) = -744.45 ± 0.17 (×4.555) kcal/mol	Prosen 1944c, Labbauf 1961, Epstein 1949
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
0.7	7046.2	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
0.7	4035.5	CH2(CH2CH2CH2CH2CH2) (g) + CH3CH2CH2CH2CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH2CH2CH3 (g)	Δ_rH°(0 K) = 5.53 ± 0.85 kcal/mol	Ruscic W1RO
0.7	8471.5	CH3CH(CH2CH2CH2CH2) (g) + CH3CH2CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH(CH3)3 (g)	Δ_rH°(0 K) = 0.30 ± 0.85 kcal/mol	Ruscic W1RO
0.6	4035.1	CH2(CH2CH2CH2CH2CH2) (g) + CH3CH2CH2CH2CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH2CH2CH3 (g)	Δ_rH°(0 K) = 5.97 ± 0.90 kcal/mol	Ruscic G3X
0.6	4035.2	CH2(CH2CH2CH2CH2CH2) (g) + CH3CH2CH2CH2CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH2CH2CH3 (g)	Δ_rH°(0 K) = 5.96 ± 0.90 kcal/mol	Ruscic G4
0.6	4035.4	CH2(CH2CH2CH2CH2CH2) (g) + CH3CH2CH2CH2CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH3CH2CH2CH2CH2CH3 (g)	Δ_rH°(0 K) = 5.76 ± 0.90 kcal/mol	Ruscic CBS-n
0.6	8471.2	CH3CH(CH2CH2CH2CH2) (g) + CH3CH2CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH(CH3)3 (g)	Δ_rH°(0 K) = 0.49 ± 0.90 kcal/mol	Ruscic G4
0.6	8471.4	CH3CH(CH2CH2CH2CH2) (g) + CH3CH2CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH(CH3)3 (g)	Δ_rH°(0 K) = 0.45 ± 0.90 kcal/mol	Ruscic CBS-n
0.6	8471.1	CH3CH(CH2CH2CH2CH2) (g) + CH3CH2CH3 (g) → CH2(CH2CH2CH2CH2) (g) + CH(CH3)3 (g)	Δ_rH°(0 K) = 0.43 ± 0.90 kcal/mol	Ruscic G3X
0.6	3966.6	CH2(CHCHCHCH) (g) → 5 C (g) + 6 H (g)	Δ_rH°(0 K) = 1123.70 ± 0.50 kcal/mol	Karton 2017
0.6	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

Top 10 species with enthalpies of formation correlated to the Δ_fH° of CH2(CH2CH2CH2CH2) (l)

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
99.2	Cyclopentane	CH2(CH2CH2CH2CH2) (g)	-43.39	-75.96	± 0.38	kJ/mol	70.1329 ± 0.0041	287-92-3*0
83.5	Cyclopentene	CH2(CH2CHCHCH2) (g)	59.92	35.65	± 0.43	kJ/mol	68.1170 ± 0.0040	142-29-0*0
73.4	Cyclopentene	CH2(CH2CHCHCH2) (l)		7.37	± 0.48	kJ/mol	68.1170 ± 0.0040	142-29-0*590
66.5	Cyclopentadiene	CH2(CHCHCHCH) (l)		110.37	± 0.56	kJ/mol	66.1011 ± 0.0040	542-92-7*590
41.5	Cyclopentadiene	CH2(CHCHCHCH) (g)	151.87	134.75	± 0.49	kJ/mol	66.1011 ± 0.0040	542-92-7*0
28.7	Carbonic acid	C(O)(OH)2 (aq, undissoc)		-698.673	± 0.028	kJ/mol	62.0248 ± 0.0012	463-79-6*1000
25.1	Water	H2O (l)		-285.804	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*590
25.1	Water	H2O (l, eq.press.)		-285.806	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*589
25.1	Water	H2O (cr,l)	-286.276	-285.804	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*500
25.1	Water	H2O (cr, l, eq.press.)	-286.278	-285.806	± 0.022	kJ/mol	18.01528 ± 0.00033	7732-18-5*499

Most Influential reactions involving CH2(CH2CH2CH2CH2) (l)

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
0.989	3970.1	CH2(CHCHCHCH) (l) + 2 H2 (g) → CH2(CH2CH2CH2CH2) (l)	Δ_rH°(298.15 K) = -51.4 ± 0.1 kcal/mol	Roth 1980, Roth 1991
0.440	3958.1	CH2(CH2CH2CH2CH2) (l) → CH2(CH2CH2CH2CH2) (g)	Δ_rH°(298.15 K) = 28.72 ± 0.07 kJ/mol	Majer 1985
0.366	3959.4	CH2(CH2CH2CH2CH2) (l) + 15/2 O2 (g) → 5 CO2 (g) + 5 H2O (l)	Δ_rH°(298.15 K) = -786.84 ± 0.14 kcal/mol	Kaarsemaker 1952, as quoted by Cox 1970
0.308	3958.3	CH2(CH2CH2CH2CH2) (l) → CH2(CH2CH2CH2CH2) (g)	Δ_rH°(298.15 K) = 6.86 ± 0.02 kcal/mol	Aston 1943, est unc
0.168	3958.2	CH2(CH2CH2CH2CH2) (l) → CH2(CH2CH2CH2CH2) (g)	Δ_rH°(298.15 K) = 6.83 ± 0.02 (×1.354) kcal/mol	McCullough 1959, note unc
0.150	3959.1	CH2(CH2CH2CH2CH2) (l) + 15/2 O2 (g) → 5 CO2 (g) + 5 H2O (l)	Δ_rH°(298.15 K) = -3290.85 ± 0.72 (×1.269) kJ/mol	Johnson 1946
0.079	3959.3	CH2(CH2CH2CH2CH2) (l) + 15/2 O2 (g) → 5 CO2 (g) + 5 H2O (l)	Δ_rH°(298.15 K) = -786.61 ± 0.30 kcal/mol	Spitzer 1947
0.077	3958.4	CH2(CH2CH2CH2CH2) (l) → CH2(CH2CH2CH2CH2) (g)	Δ_rH°(298.15 K) = 6.86 ± 0.04 kcal/mol	Prosen 1946
0.037	3965.1	CH2(CH2CHCHCH2) (l) + H2 (g) → CH2(CH2CH2CH2CH2) (l)	Δ_rH°(298.15 K) = -26.7 ± 0.4 kcal/mol	Roth 1980a, note unc
0.016	3965.2	CH2(CH2CHCHCH2) (l) + H2 (g) → CH2(CH2CH2CH2CH2) (l)	Δ_rH°(298.15 K) = -26.2 ± 0.6 kcal/mol	Rogers 1971, est unc
0.005	3965.3	CH2(CH2CHCHCH2) (l) + H2 (g) → CH2(CH2CH2CH2CH2) (l)	Δ_rH°(298.15 K) = -25.7 ± 0.5 (×2.181) kcal/mol	Turner 1968a, Turner 1968, est unc

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. 1.176 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		T. L. Nguyen et al, ongoing studies (2024)
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.