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].

Allene

Formula: CH2CCH2 (g)

CAS RN: 463-49-0

ATcT ID: 463-49-0*0

SMILES: C=C=C

InChI: InChI=1S/C3H4/c1-3-2/h1-2H2

InChIKey: IYABWNGZIDDRAK-UHFFFAOYSA-N

Hills Formula: C3H4

2D Image:

Aliases: CH2CCH2; Allene; Propadiene; 1,2-Propadiene; Bis(methylene)methane; Dimethylenemethane; sym-Allylene; H2CCCH2; CH2=C=CH2; UN 2200

Relative Molecular Mass: 40.0639 ± 0.0024

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
197.47	190.01	± 0.22	kJ/mol

3D Image of CH2CCH2 (g)

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Top contributors to the provenance of Δ_fH° of CH2CCH2 (g)

The 20 contributors listed below account only for 41.8% of the provenance of Δ_fH° of CH2CCH2 (g).
A total of 641 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
10.3	3472.2	CH3CCH (g) → CH2CCH2 (g)	Δ_rG°(521.5 K) = 1.580 ± 0.062 kcal/mol	Cordes 1959, 3rd Law
3.3	3469.1	CH2CCH2 (g) + 2 H2 (g) → CH3CH2CH3 (g)	Δ_rH°(355.15 K) = -71.295 ± 0.20 (×1.091) kcal/mol	Kistiakowsky 1936
3.1	3471.15	CH2CCH2 (g) + CH4 (g) → 2 CH2CH2 (g)	Δ_rH°(0 K) = -8.78 ± 0.8 kJ/mol	Ferguson 2013, est unc
2.9	3470.11	CH2CCH2 (g) + CH3CH3 (g) → CH3CHCH2 (g) + CH2CH2 (g)	Δ_rH°(0 K) = -8.02 ± 0.20 kcal/mol	Karton 2009b, Karton 2011
1.9	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
1.8	3465.3	CH2CCH2 (g) → 3 C (g) + 4 H (g)	Δ_rH°(0 K) = 669.37 ± 0.30 kcal/mol	Karton 2009b, Karton 2011
1.8	3465.4	CH2CCH2 (g) → 3 C (g) + 4 H (g)	Δ_rH°(0 K) = 669.33 ± 0.30 kcal/mol	Karton 2008
1.8	3465.5	CH2CCH2 (g) → 3 C (g) + 4 H (g)	Δ_rH°(0 K) = 669.3 ± 0.3 kcal/mol	Bakowies 2020
1.8	3471.11	CH2CCH2 (g) + CH4 (g) → 2 CH2CH2 (g)	Δ_rH°(0 K) = -2.24 ± 0.25 kcal/mol	Karton 2009b, Karton 2011
1.7	3459.1	CH3CCH (g) + 4 O2 (g) → 3 CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -463.131 ± 0.204 kcal/mol	Wagman 1945, Wagman 1945a
1.4	3470.13	CH2CCH2 (g) + CH3CH3 (g) → CH3CHCH2 (g) + CH2CH2 (g)	Δ_rH°(0 K) = -32.08 ± 0.8 (×1.509) kJ/mol	Ferguson 2013, est unc
1.3	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	3470.10	CH2CCH2 (g) + CH3CH3 (g) → CH3CHCH2 (g) + CH2CH2 (g)	Δ_rH°(0 K) = -7.89 ± 0.30 kcal/mol	Karton 2011
1.2	3471.13	CH2CCH2 (g) + CH4 (g) → 2 CH2CH2 (g)	Δ_rH°(0 K) = -2.38 ± 0.3 kcal/mol	Wheeler 2007
1.1	2268.11	CO (g) → C (g) + O (g)	Δ_rH°(0 K) = 1071.92 ± 0.10 kJ/mol	Thorpe 2021
1.0	3474.10	CH3CCH (g) → CH2CCH2 (g)	Δ_rH°(0 K) = 4.19 ± 0.8 kJ/mol	Ferguson 2013, est unc
0.9	3461.14	CH3CCH (g) + CH3CH3 (g) → CH3CH2CH3 (g) + HCCH (g)	Δ_rH°(0 K) = 21.92 ± 0.8 kJ/mol	Ferguson 2013, est unc
0.8	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	2529.1	CH2CH2 (g) + 3 O2 (g) → 2 CO2 (g) + 2 H2O (cr,l)	Δ_rH°(298.15 K) = -1411.18 ± 0.30 kJ/mol	Rossini 1937
0.7	3462.13	CH3CCH (g) + CH2CH2 (g) → CH3CHCH2 (g) + HCCH (g)	Δ_rH°(0 K) = 10.57 ± 0.8 kJ/mol	Ferguson 2013, est unc

Top 10 species with enthalpies of formation correlated to the Δ_fH° of CH2CCH2 (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
99.8	Allene cation	[CH2CCH2]+ (g)	1132.26	1125.11	± 0.22	kJ/mol	40.0633 ± 0.0024	65812-77-3*0
65.0	Propyne	CH3CCH (g)	192.70	185.55	± 0.20	kJ/mol	40.0639 ± 0.0024	74-99-7*0
39.1	Ethylene	CH2CH2 (g)	60.89	52.38	± 0.11	kJ/mol	28.0532 ± 0.0016	74-85-1*0
39.1	Ethylene cation	[CH2CH2]+ (g)	1075.21	1067.99	± 0.11	kJ/mol	28.0526 ± 0.0016	34470-02-5*0
36.9	Carbon cation	C+ (g)	1797.834	1803.432	± 0.039	kJ/mol	12.01015 ± 0.00080	14067-05-1*0
36.9	Carbon	C (g, triplet)	711.381	716.866	± 0.039	kJ/mol	12.01070 ± 0.00080	7440-44-0*1
36.9	Carbon	C (g)	711.381	716.866	± 0.039	kJ/mol	12.01070 ± 0.00080	7440-44-0*0
36.9	Carbon	C (g, quintuplet)	1114.944	1120.091	± 0.039	kJ/mol	12.01070 ± 0.00080	7440-44-0*3
36.9	Carbon	C (g, singlet)	833.312	838.459	± 0.039	kJ/mol	12.01070 ± 0.00080	7440-44-0*2
36.9	Carbon dication	[C]+2 (g)	4150.451	4155.597	± 0.039	kJ/mol	12.00960 ± 0.00080	16092-61-8*0

Most Influential reactions involving CH2CCH2 (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
0.995	3466.1	CH2CCH2 (g) → [CH2CCH2]+ (g)	Δ_rH°(0 K) = 78142.92 ± 1.00 cm-1	Schulenburg 2009, Schulenburg 2010, note unc
0.444	3472.2	CH3CCH (g) → CH2CCH2 (g)	Δ_rG°(521.5 K) = 1.580 ± 0.062 kcal/mol	Cordes 1959, 3rd Law
0.255	9053.6	CH2CCCCH2 (g) + CH2CCH2 (g) → 2 CH2CCCH2 (g)	Δ_rH°(0 K) = 6.45 ± 2.00 kJ/mol	Klippenstein 2017
0.223	6858.9	OCCCO (g) + 2 CH2CH2 (g) → 2 CH2CO (g) + CH2CCH2 (g)	Δ_rH°(0 K) = 78.36 ± 2.00 kJ/mol	Klippenstein 2017
0.173	8448.4	CH2CCHCl (g) + CH2CH2 (g) → CH2CCH2 (g) + CH2CHCl (g)	Δ_rH°(0 K) = -3.82 ± 0.9 kcal/mol	Ruscic W1RO
0.173	9048.6	HCCCHCCH2 (g) + CH2CCH (g) → CHCCHCCH (g) + CH2CCH2 (g)	Δ_rH°(0 K) = -21.40 ± 2.00 kJ/mol	Klippenstein 2017
0.164	3852.6	CH3CCCH2 (g) + CH2CCH2 (g) → CH2CCCH2 (g) + CH3CCH2 (g)	Δ_rH°(0 K) = 75.20 ± 2.00 kJ/mol	Klippenstein 2017
0.142	3485.9	CH2CCH2 (g) → CH2(CHCH) (g)	Δ_rH°(0 K) = 22.59 ± 0.25 kcal/mol	Karton 2008
0.140	8448.2	CH2CCHCl (g) + CH2CH2 (g) → CH2CCH2 (g) + CH2CHCl (g)	Δ_rH°(0 K) = -3.51 ± 1.0 kcal/mol	Ruscic G4
0.132	9102.5	CH2CCCHCH3 (g) + CH2CCH2 (g) → CH2CCCH2 (g) + CH3CHCCH2 (g)	Δ_rH°(0 K) = 1.17 ± 0.85 kcal/mol	Ruscic W1RO
0.120	8480.5	OCC(CHCHCHCH) (g) + CH2CCH2 (g) → CH2CCO (g) + CH2C(CHCHCHCH) (g)	Δ_rH°(0 K) = 11.69 ± 0.85 kcal/mol	Ruscic W1RO
0.118	9102.1	CH2CCCHCH3 (g) + CH2CCH2 (g) → CH2CCCH2 (g) + CH3CHCCH2 (g)	Δ_rH°(0 K) = 1.20 ± 0.90 kcal/mol	Ruscic G3X
0.118	9102.4	CH2CCCHCH3 (g) + CH2CCH2 (g) → CH2CCCH2 (g) + CH3CHCCH2 (g)	Δ_rH°(0 K) = 1.08 ± 0.90 kcal/mol	Ruscic CBS-n
0.118	9102.2	CH2CCCHCH3 (g) + CH2CCH2 (g) → CH2CCCH2 (g) + CH3CHCCH2 (g)	Δ_rH°(0 K) = 1.16 ± 0.90 kcal/mol	Ruscic G4
0.117	7822.5	2 CH2CCO (g) → CH2CCH2 (g) + OCCCO (g)	Δ_rH°(0 K) = -38.91 ± 0.85 kcal/mol	Ruscic W1RO
0.116	8448.1	CH2CCHCl (g) + CH2CH2 (g) → CH2CCH2 (g) + CH2CHCl (g)	Δ_rH°(0 K) = -3.60 ± 1.1 kcal/mol	Ruscic G3X
0.107	8480.2	OCC(CHCHCHCH) (g) + CH2CCH2 (g) → CH2CCO (g) + CH2C(CHCHCHCH) (g)	Δ_rH°(0 K) = 11.66 ± 0.90 kcal/mol	Ruscic G4
0.107	8480.1	OCC(CHCHCHCH) (g) + CH2CCH2 (g) → CH2CCO (g) + CH2C(CHCHCHCH) (g)	Δ_rH°(0 K) = 11.77 ± 0.90 kcal/mol	Ruscic G3X
0.107	8480.4	OCC(CHCHCHCH) (g) + CH2CCH2 (g) → CH2CCO (g) + CH2C(CHCHCHCH) (g)	Δ_rH°(0 K) = 12.14 ± 0.90 kcal/mol	Ruscic CBS-n
0.106	3887.6	CH3CHCCH2 (g) + CH2CCH (g) → CH3CHCCH (g) + CH2CCH2 (g)	Δ_rH°(0 K) = -3.90 ± 2.00 kJ/mol	Klippenstein 2017

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.