Selected ATcT [1, 2] enthalpy of formation based on version 1.148 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.140 to include species relevant to a recent study of the role of atmospheric methanediol[4].

Indene cation

Formula: [C6H4(CHCHCH2)]+ (g)

CAS RN: 42949-13-3

ATcT ID: 42949-13-3*0

SMILES: c1ccc2c(c1)[CH2+]C=C2

InChI: InChI=1S/C9H8/c1-2-5-9-7-3-6-8(9)4-1/h1-6H,7H2/q+1

Hills Formula: C9H8+

2D Image:

Aliases: [C6H4(CHCHCH2)]+; Indene cation; Indene ion (1+); C6H4(CHCHCH2)+; InChiKey=GJODXRREDFRAMS-UHFFFAOYSA-N

Relative Molecular Mass: 116.1593 ± 0.0072

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
970.05	946.81	± 0.76	kJ/mol

3D Image of [C6H4(CHCHCH2)]+ (g)

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Top contributors to the provenance of Δ_fH° of [C6H4(CHCHCH2)]+ (g)

The 20 contributors listed below account only for 57.9% of the provenance of Δ_fH° of [C6H4(CHCHCH2)]+ (g).
A total of 56 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
14.2	6870.1	C6H4(CHCHCH2) (cr,l) + 11 O2 (g) → 9 CO2 (g) + 4 H2O (cr,l)	Δ_rH°(298.15 K) = -1146.12 ± 0.30 kcal/mol	Stull 1961
5.1	6871.2	C6H4(CHCHCH2) (cr,l) → C6H4(CHCHCH2) (g)	Δ_rH°(298.15 K) = 50.29 ± 1. kJ/mol	Verevkin 2011, est unc
2.9	6868.5	3 C6H4(CHCHCH2) (g) + CH4 (g) → 14/3 C6H6 (g)	Δ_rH°(0 K) = -4.91 ± 2.7 kcal/mol	Ruscic W1RO
2.9	6869.5	C6H4(CHCHCH2) (g) + 1/2 CH2CH2 (g) → 5/3 C6H6 (g)	Δ_rH°(0 K) = -11.57 ± 0.9 kcal/mol	Ruscic W1RO
2.4	6868.4	3 C6H4(CHCHCH2) (g) + CH4 (g) → 14/3 C6H6 (g)	Δ_rH°(0 K) = -2.55 ± 3.0 kcal/mol	Ruscic CBS-n
2.4	6868.2	3 C6H4(CHCHCH2) (g) + CH4 (g) → 14/3 C6H6 (g)	Δ_rH°(0 K) = -2.00 ± 3.0 kcal/mol	Ruscic G4
2.4	6869.2	C6H4(CHCHCH2) (g) + 1/2 CH2CH2 (g) → 5/3 C6H6 (g)	Δ_rH°(0 K) = -10.53 ± 1.0 kcal/mol	Ruscic G4
2.4	6869.4	C6H4(CHCHCH2) (g) + 1/2 CH2CH2 (g) → 5/3 C6H6 (g)	Δ_rH°(0 K) = -11.20 ± 1.0 kcal/mol	Ruscic CBS-n
2.3	6864.1	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 65721 ± 10 cm-1	Qin 2011, note unc2
2.3	6871.1	C6H4(CHCHCH2) (cr,l) → C6H4(CHCHCH2) (g)	Δ_rH°(298.15 K) = 50.64 ± 1.50 kJ/mol	Roux 2008, Roux 2008, Stull 1961
2.0	6868.1	3 C6H4(CHCHCH2) (g) + CH4 (g) → 14/3 C6H6 (g)	Δ_rH°(0 K) = -1.78 ± 3.3 kcal/mol	Ruscic G3X
1.9	6869.1	C6H4(CHCHCH2) (g) + 1/2 CH2CH2 (g) → 5/3 C6H6 (g)	Δ_rH°(0 K) = -10.44 ± 1.1 kcal/mol	Ruscic G3X
1.8	6867.5	C6H4(CHCHCH2) (g) + CH2CH2 (g) → C6H6 (g) + CH2(CHCHCHCH) (g)	Δ_rH°(0 K) = 1.18 ± 0.9 kcal/mol	Ruscic W1RO
1.8	6866.5	C6H4(CHCHCH2) (g) + CH2CHCHCH2 (g) → C6H5CHCH2 (g) + CH2(CHCHCHCH) (g)	Δ_rH°(0 K) = 2.46 ± 0.85 kcal/mol	Ruscic W1RO
1.8	3853.1	CH2(CHCHCHCH) (g) + 2 H2 (g) → CH2(CH2CH2CH2CH2) (g)	Δ_rH°(355.15 K) = -50.907 ± 0.200 kcal/mol	Kistiakowsky 1936
1.7	6856.2	C6H4(CH2CH2CH2) (cr,l) + 23/2 O2 (g) → 9 CO2 (g) + 5 H2O (cr,l)	Δ_rH°(298.15 K) = -1190.80 ± 0.33 kcal/mol	Good 1971a
1.7	6863.6	C6H4(CHCHCH2) (g) → 9 C (g) + 8 H (g)	Δ_rH°(0 K) = 7949.5 ± 5.2 kJ/mol	Karton 2021, Karton 2021
1.6	6866.1	C6H4(CHCHCH2) (g) + CH2CHCHCH2 (g) → C6H5CHCH2 (g) + CH2(CHCHCHCH) (g)	Δ_rH°(0 K) = 3.34 ± 0.90 kcal/mol	Ruscic G3X
1.6	6866.2	C6H4(CHCHCH2) (g) + CH2CHCHCH2 (g) → C6H5CHCH2 (g) + CH2(CHCHCHCH) (g)	Δ_rH°(0 K) = 3.29 ± 0.90 kcal/mol	Ruscic G4
1.6	6866.4	C6H4(CHCHCH2) (g) + CH2CHCHCH2 (g) → C6H5CHCH2 (g) + CH2(CHCHCHCH) (g)	Δ_rH°(0 K) = 3.49 ± 0.90 kcal/mol	Ruscic CBS-n

Top 10 species with enthalpies of formation correlated to the Δ_fH° of [C6H4(CHCHCH2)]+ (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
98.7	Indene	C6H4(CHCHCH2) (g)	183.88	159.98	± 0.75	kJ/mol	116.1598 ± 0.0072	95-13-6*0
59.3	Indene	C6H4(CHCHCH2) (cr,l)	117.30	110.01	± 0.86	kJ/mol	116.1598 ± 0.0072	95-13-6*500
31.3	Cyclopentadiene	CH2(CHCHCHCH) (g)	151.82	134.70	± 0.55	kJ/mol	66.1011 ± 0.0040	542-92-7*0
30.2	Indane	C6H4(CH2CH2CH2) (g)	90.94	59.91	± 0.76	kJ/mol	118.1757 ± 0.0072	496-11-7*0
28.6	Indane	C6H4(CH2CH2CH2) (cr,l)	25.47	11.00	± 0.76	kJ/mol	118.1757 ± 0.0072	496-11-7*500
25.8	Benzene cation	[C6H6]+ (g)	992.62	976.15	± 0.21	kJ/mol	78.1113 ± 0.0048	34504-50-2*0
25.8	Benzene	C6H6 (g)	100.72	83.21	± 0.21	kJ/mol	78.1118 ± 0.0048	71-43-2*0
25.8	Benzene	C6H6 (cr,l)	50.82	49.27	± 0.21	kJ/mol	78.1118 ± 0.0048	71-43-2*500
19.8	Norbornadiene	(CHCH)(CHCH2CH)(CHCH) (g)	268.08	242.64	± 0.94	kJ/mol	92.1384 ± 0.0056	121-46-0*0
18.0	Carbonic acid	C(O)(OH)2 (aq, undissoc)		-698.670	± 0.028	kJ/mol	62.0248 ± 0.0012	463-79-6*1000

Most Influential reactions involving [C6H4(CHCHCH2)]+ (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
0.966	6864.1	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 65721 ± 10 cm-1	Qin 2011, note unc2
0.014	6864.4	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 8.14 ± 0.01 eV	Dewar 1970
0.012	6864.2	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 65632 ± 20 (×4.458) cm-1	Kendler 1995, note unc2
0.003	6864.3	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 8.15 ± 0.02 eV	Gusten 1976
0.000	6864.10	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 8.171 ± 0.040 eV	Ruscic W1RO
0.000	6864.5	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 8.13 ± 0.05 eV	Eland 1968a
0.000	6864.7	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 8.176 ± 0.073 eV	Ruscic G4
0.000	6864.9	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 8.192 ± 0.075 eV	Ruscic CBS-n
0.000	6864.6	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 8.229 ± 0.093 eV	Ruscic G3X
0.000	6864.8	C6H4(CHCHCH2) (g) → [C6H4(CHCHCH2)]+ (g)	Δ_rH°(0 K) = 8.189 ± 0.099 eV	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. 1.148 of the Thermochemical Network (2023); available at ATcT.anl.gov
4		T. L. Nguyen, J. Peeters, J.-F. Müller, A. Perera, D. H. Bross, B. Ruscic, and J. F. Stanton, Methanediol from Cloud-Processed Formaldehyde is Only a Minor Source of Atmospheric Formic Acid Natl. Acad. Sci. 120, e2304650120/1-8 (2023) [DOI: 10.1073/pnas.2304650120]
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.