Selected ATcT [1, 2] enthalpy of formation based on version 1.130 of the Thermochemical Network [3]

This version of ATcT results[4] was generated by additional expansion of version 1.128 [5,6] to include with the calculations provided in reference [4].

p-Benzyne

Formula: C6H4 (g, triplet)
CAS RN: 3355-34-8
ATcT ID: 3355-34-8*1
SMILES: c1c[c]cc[c]1
InChI: InChI=1S/C6H4/c1-2-4-6-5-3-1/h1-2,5-6H
InChIKey: AIESRBVWAFETPR-UHFFFAOYSA-N
Hills Formula: C6H4

2D Image:

c1c[c]cc[c]1
Aliases: C6H4; p-Benzyne; 1,4-Benzyne; p-Phenylene; 1,4-Phenylene; p-Didehydrobenzene; 1,4-Didehydrobenzene; 2,5-Cyclohexadiene-1,4-diylidene; p-C6H4
Relative Molecular Mass: 76.0960 ± 0.0048

   ΔfH°(0 K)   ΔfH°(298.15 K)UncertaintyUnits
603.5594.2± 1.2kJ/mol

3D Image of C6H4 (g, triplet)

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Top contributors to the provenance of ΔfH° of C6H4 (g, triplet)

The 20 contributors listed below account only for 66.9% of the provenance of ΔfH° of C6H4 (g, triplet).
A total of 60 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
15.26572.7 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1082.46 ± 0.70 kcal/molKarton 2009a
5.16579.1 C6H4 (g, singlet) → C6H4 (g, triplet) ΔrH°(0 K) = 0.165 ± 0.016 eVWenthold 1998
4.66575.1 [C6H4]- (g) → C6H4 (g, triplet) ΔrH°(0 K) = 1.430 ± 0.015 eVWenthold 1998
4.06572.6 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1082.27 ± 1.35 kcal/molKarton 2009a
3.56580.5 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.23 ± 0.9 kcal/molRuscic W1RO
3.36572.5 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1082.70 ± 1.50 kcal/molRuscic W1RO
2.96572.4 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1083.40 ± 1.60 kcal/molRuscic CBS-n
2.96572.2 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1082.50 ± 1.60 kcal/molRuscic G4
2.96580.4 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.70 ± 1.0 kcal/molRuscic CBS-n
2.96580.2 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.15 ± 1.0 kcal/molRuscic G4
2.56572.1 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1081.16 ± 1.72 kcal/molRuscic G3X
2.46580.1 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.08 ± 1.1 kcal/molRuscic G3X
2.16550.9 C6H4 (g, singlet) → HCCCCH (g) HCCH (g) ΔrH°(0 K) = 52.4 ± 0.5 kcal/molZhang 2007
2.06551.7 C6H6 (g) → C6H4 (g, singlet) H2 (g) ΔrH°(0 K) = 88.10 ± 0.6 kcal/molKarton 2009a
1.96571.6 C6H4 (g, singlet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1087.73 ± 0.70 (×1.915) kcal/molKarton 2009a
1.96571.5 C6H4 (g, singlet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1085.45 ± 1.35 kcal/molKarton 2009a
1.76580.3 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.47 ± 1.3 kcal/molRuscic CBS-n
1.56571.4 C6H4 (g, singlet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1085.44 ± 1.50 kcal/molRuscic W1RO
1.46588.4 [C6H4]- (g) → [C6H4]- (g) ΔrH°(0 K) = -11.49 ± 0.9 kcal/molRuscic W1RO
1.46571.2 C6H4 (g, singlet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1087.65 ± 1.60 kcal/molRuscic G4

Top 10 species with enthalpies of formation correlated to the ΔfH° of C6H4 (g, triplet)

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 Image    ΔfH°(0 K)    ΔfH°(298.15 K) Uncertainty Units Relative
Molecular
Mass
ATcT ID
71.0 p-BenzyneC6H4 (g, singlet)c1c[c]cc[c]1587.0577.5± 1.2kJ/mol76.0960 ±
0.0048
3355-34-8*2
71.0 p-BenzyneC6H4 (g)c1c[c]cc[c]1587.0577.6± 1.2kJ/mol76.0960 ±
0.0048
3355-34-8*0
70.9 p-Benzyne anion[C6H4]- (g)c1c[c]cc[c-]1465.0455.5± 1.3kJ/mol76.0965 ±
0.0048
219298-17-6*0
45.6 o-BenzyneC6H4 (g, triplet)C1=CC#CC=C1625.7616.3± 1.1kJ/mol76.0960 ±
0.0048
462-80-6*1
44.1 o-Benzyne anion[C6H4]- (g)C1=CC#CC=[CH-]1413.77404.66± 0.95kJ/mol76.0965 ±
0.0048
100569-88-8*0
43.6 o-BenzyneC6H4 (g)C1=CC#CC=C1468.16459.25± 0.86kJ/mol76.0960 ±
0.0048
462-80-6*0
43.6 o-BenzyneC6H4 (g, singlet)C1=CC#CC=C1468.16459.25± 0.86kJ/mol76.0960 ±
0.0048
462-80-6*2
38.0 m-BenzyneC6H4 (g, singlet)c1[c]ccc[c]1527.0518.5± 1.2kJ/mol76.0960 ±
0.0048
1828-89-3*2
38.0 m-BenzyneC6H4 (g)c1[c]ccc[c]1527.0518.5± 1.2kJ/mol76.0960 ±
0.0048
1828-89-3*0
36.9 m-Benzyne anion[C6H4]- (g)c1[c]ccc[c-]1444.2435.3± 1.3kJ/mol76.0965 ±
0.0048
249589-31-9*0

Most Influential reactions involving C6H4 (g, triplet)

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
0.4036575.1 [C6H4]- (g) → C6H4 (g, triplet) ΔrH°(0 K) = 1.430 ± 0.015 eVWenthold 1998
0.3386579.1 C6H4 (g, singlet) → C6H4 (g, triplet) ΔrH°(0 K) = 0.165 ± 0.016 eVWenthold 1998
0.1596572.7 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1082.46 ± 0.70 kcal/molKarton 2009a
0.0956580.5 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.23 ± 0.9 kcal/molRuscic W1RO
0.0776580.2 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.15 ± 1.0 kcal/molRuscic G4
0.0776580.4 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.70 ± 1.0 kcal/molRuscic CBS-n
0.0646580.1 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.08 ± 1.1 kcal/molRuscic G3X
0.0456580.3 C6H4 (g, triplet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.47 ± 1.3 kcal/molRuscic CBS-n
0.0426572.6 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1082.27 ± 1.35 kcal/molKarton 2009a
0.0346575.4 [C6H4]- (g) → C6H4 (g, triplet) ΔrH°(0 K) = 1.486 ± 0.050 (×1.022) eVRuscic W1RO
0.0346572.5 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1082.70 ± 1.50 kcal/molRuscic W1RO
0.0326579.5 C6H4 (g, singlet) → C6H4 (g, triplet) ΔrH°(0 K) = 3.17 ± 1.2 kcal/molKarton 2009a
0.0306579.4 C6H4 (g, singlet) → C6H4 (g, triplet) ΔrH°(0 K) = 958 ± 420 (×1.022) cm-1Ruscic W1RO
0.0306572.4 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1083.40 ± 1.60 kcal/molRuscic CBS-n
0.0306572.2 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1082.50 ± 1.60 kcal/molRuscic G4
0.0276579.2 C6H4 (g, singlet) → C6H4 (g, triplet) ΔrH°(0 K) = 1801 ± 450 cm-1Ruscic G4
0.0266572.1 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1081.16 ± 1.72 kcal/molRuscic G3X
0.0256579.6 C6H4 (g, singlet) → C6H4 (g, triplet) ΔrH°(0 K) = 5.27 ± 0.8 (×1.682) kcal/molKarton 2009a
0.0246575.2 [C6H4]- (g) → C6H4 (g, triplet) ΔrH°(0 K) = 1.437 ± 0.061 eVRuscic G4
0.0106572.3 C6H4 (g, triplet) → 6 C (g) + 4 H (g) ΔrH°(0 K) = 1079.77 ± 2.16 (×1.269) kcal/molRuscic 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 21st 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. 1.130 of the Thermochemical Network. Argonne National Laboratory, Lemont, Illinois 2023; available at ATcT.anl.gov
[DOI: 10.17038/CSE/1997229]
4   N. Genossar, P. B. Changala, B. Gans, J.-C. Loison, S. Hartweg, M.-A. Martin-Drumel, G. A. Garcia, J. F. Stanton, B. Ruscic, and J. H. Baraban
Ring-Opening Dynamics of the Cyclopropyl Radical and Cation: the Transition State Nature of the Cyclopropyl Cation
J. Am. Chem. Soc. 144, 18518-18525 (2022) [DOI: 10.1021/jacs.2c07740]
5   B. Ruscic and D. H. Bross
Active Thermochemical Tables: The Thermophysical and Thermochemical Properties of Methyl, CH3, and Methylene, CH2, Corrected for Nonrigid Rotor and Anharmonic Oscillator Effects.
Mol. Phys. e1969046 (2021) [DOI: 10.1080/00268976.2021.1969046]
6   J. H. Thorpe, J. L. Kilburn, D. Feller, P. B. Changala, D. H. Bross, B. Ruscic, and J. F. Stanton,
Elaborated Thermochemical Treatment of HF, CO, N2, and H2O: Insight into HEAT and Its Extensions
J. Chem. Phys. 155, 184109 (2021) [DOI: 10.1063/5.0069322]
7   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]
8   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 [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.