Selected ATcT [1, 2] enthalpy of formation based on version 1.156 of the Thermochemical Network [3]

This version of ATcT results[3] was generated by additional expansion of version 1.148 to include species relevant to a recent study of the oxidation of ethylene [4] as well as new measurements that led to refining the thermochemistry of CF and SiF and their cations [5].

1,2-Difluoroacetylene

Formula: FCCF (g)

CAS RN: 689-99-6

ATcT ID: 689-99-6*0

SMILES: FC#CF

InChI: InChI=1S/C2F2/c3-1-2-4

InChIKey: BWTZYYGAOGUPFQ-UHFFFAOYSA-N

Hills Formula: C2F2

2D Image:

Aliases: FCCF; 1,2-Difluoroacetylene; Difluoroacetylene; Difluoroethyne; 1,2-Difluoroethyne; Perfluoroethyne; Perfluoroacetylene; C2F2

Relative Molecular Mass: 62.0182 ± 0.0016

Δ_fH°(0 K)	Δ_fH°(298.15 K)	Uncertainty	Units
2.85	5.68	± 0.63	kJ/mol

3D Image of FCCF (g)

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

The 20 contributors listed below account only for 80.8% of the provenance of Δ_fH° of FCCF (g).
A total of 51 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
23.5	6570.12	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 376.20 ± 0.30 kcal/mol	Karton 2011
9.3	6588.12	HCCF (g) + CH3F (g) → FCCF (g) + CH4 (g)	Δ_rH°(0 K) = 14.03 ± 0.20 kcal/mol	Karton 2011
8.4	6570.15	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 376.21 ± 0.5 kcal/mol	Feller 2011, est unc
6.7	6570.11	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 376.01 ± 0.56 kcal/mol	Karton 2011
6.1	6587.12	HCCH (g) + CH3F (g) → HCCF (g) + CH4 (g)	Δ_rH°(0 K) = 8.81 ± 0.20 kcal/mol	Karton 2011
5.0	6585.12	HCCF (g) → 2 C (g) + H (g) + F (g)	Δ_rH°(0 K) = 385.07 ± 0.30 kcal/mol	Karton 2011
4.1	6588.11	HCCF (g) + CH3F (g) → FCCF (g) + CH4 (g)	Δ_rH°(0 K) = 14.05 ± 0.30 kcal/mol	Karton 2011
4.1	6570.16	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 1575.2 ± 3.0 kJ/mol	Klopper 2010a
2.7	6587.11	HCCH (g) + CH3F (g) → HCCF (g) + CH4 (g)	Δ_rH°(0 K) = 8.78 ± 0.30 kcal/mol	Karton 2011
1.4	6585.11	HCCF (g) → 2 C (g) + H (g) + F (g)	Δ_rH°(0 K) = 384.92 ± 0.56 kcal/mol	Karton 2011
1.2	6175.7	4 CH3F (g) → CF4 (g) + 3 CH4 (g)	Δ_rH°(0 K) = -218.8 ± 2.5 kJ/mol	Klopper 2010a, est unc
1.1	6570.10	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 375.99 ± 1.35 kcal/mol	Karton 2011
0.9	6570.8	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 376.98 ± 1.50 kcal/mol	Ruscic W1RO, Parthiban 2002
0.8	6585.14	HCCF (g) → 2 C (g) + H (g) + F (g)	Δ_rH°(0 K) = 1610.5 ± 3.0 kJ/mol	Klopper 2010a
0.8	6570.14	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 377.06 ± 1.6 kcal/mol	Haworth 2000, est unc
0.8	6570.13	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 376.240 ± 1.6 kcal/mol	Bauschlicher 2000
0.8	6570.4	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 375.85 ± 1.60 kcal/mol	Ruscic G4
0.7	6572.8	[FCCF]+ (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 118.76 ± 1.50 kcal/mol	Ruscic W1RO
0.7	6570.3	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 377.48 ± 1.72 kcal/mol	Ruscic G3X
0.6	6572.4	[FCCF]+ (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 118.37 ± 1.60 kcal/mol	Ruscic G4

Top 10 species with enthalpies of formation correlated to the Δ_fH° of FCCF (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
75.8	Fluoroacetylene	HCCF (g)	104.99	105.70	± 0.39	kJ/mol	44.0277 ± 0.0016	2713-09-9*0
45.0	1,2-Difluoroacetylene cation	[FCCF]+ (g)	1081.7	1084.5	± 1.3	kJ/mol	62.0177 ± 0.0016	268566-70-7*0
31.8	Fluoromethane	CH3F (g)	-227.45	-235.48	± 0.24	kJ/mol	34.03292 ± 0.00083	593-53-3*0
28.3	Difluorovinylidene	CCF2 (g)	129.4	130.6	± 2.2	kJ/mol	62.0182 ± 0.0016	41895-33-4*0
27.4	Difluorovinylidene anion	[CCF2]- (g)	-88.2	-87.1	± 2.3	kJ/mol	62.0188 ± 0.0016	107693-92-5*0
25.6	Difluorovinylidene cation	[CCF2]+ (g)	1181.5	1183.0	± 2.3	kJ/mol	62.0177 ± 0.0016	268566-71-8*0
19.1	Fluoroethynide	[CCF]- (g)	133.3	137.5	± 1.5	kJ/mol	43.0204 ± 0.0016	85905-56-2*0
17.5	Fluoroethynyl	CCF (g)	445.3	449.8	± 1.6	kJ/mol	43.0198 ± 0.0016	22533-50-2*0
16.5	Fluoromethane	CH3F (l)		-245.75	± 0.45	kJ/mol	34.03292 ± 0.00083	593-53-3*590
13.0	Carbon	C (g)	711.400	716.885	± 0.040	kJ/mol	12.01070 ± 0.00080	7440-44-0*0

Most Influential reactions involving FCCF (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
0.347	6586.12	HCCH (g) + FCCF (g) → 2 HCCF (g)	Δ_rH°(0 K) = -5.22 ± 0.20 kcal/mol	Karton 2011
0.343	6571.2	FCCF (g) → [FCCF]+ (g)	Δ_rH°(0 K) = 11.18 ± 0.02 eV	Bieri 1977a, est unc
0.343	6571.1	FCCF (g) → [FCCF]+ (g)	Δ_rH°(0 K) = 11.18 ± 0.02 eV	Bieri 1980, est unc
0.251	6588.12	HCCF (g) + CH3F (g) → FCCF (g) + CH4 (g)	Δ_rH°(0 K) = 14.03 ± 0.20 kcal/mol	Karton 2011
0.240	6570.12	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 376.20 ± 0.30 kcal/mol	Karton 2011
0.166	6579.5	CCF2 (g) → FCCF (g)	Δ_rH°(0 K) = -30.63 ± 1.2 kcal/mol	Ruscic W1RO
0.154	6586.11	HCCH (g) + FCCF (g) → 2 HCCF (g)	Δ_rH°(0 K) = -5.27 ± 0.30 kcal/mol	Karton 2011
0.142	6579.2	CCF2 (g) → FCCF (g)	Δ_rH°(0 K) = -29.37 ± 1.3 kcal/mol	Ruscic G4
0.142	6579.4	CCF2 (g) → FCCF (g)	Δ_rH°(0 K) = -30.19 ± 1.3 kcal/mol	Ruscic CBS-n
0.122	6579.1	CCF2 (g) → FCCF (g)	Δ_rH°(0 K) = -30.85 ± 1.4 kcal/mol	Ruscic G3X
0.111	6588.11	HCCF (g) + CH3F (g) → FCCF (g) + CH4 (g)	Δ_rH°(0 K) = 14.05 ± 0.30 kcal/mol	Karton 2011
0.093	6579.3	CCF2 (g) → FCCF (g)	Δ_rH°(0 K) = -31.17 ± 1.6 kcal/mol	Ruscic CBS-n
0.086	6570.15	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 376.21 ± 0.5 kcal/mol	Feller 2011, est unc
0.085	6571.10	FCCF (g) → [FCCF]+ (g)	Δ_rH°(0 K) = 11.198 ± 0.040 eV	Ruscic W1RO
0.069	6570.11	FCCF (g) → 2 C (g) + 2 F (g)	Δ_rH°(0 K) = 376.01 ± 0.56 kcal/mol	Karton 2011
0.060	6579.6	CCF2 (g) → FCCF (g)	Δ_rH°(0 K) = -29.1 ± 2 kcal/mol	Breidung 2001, est unc
0.059	6598.5	FCCF (g) → CCF (g) + F (g)	Δ_rH°(0 K) = 124.82 ± 1.50 kcal/mol	Ruscic W1RO
0.052	6598.2	FCCF (g) → CCF (g) + F (g)	Δ_rH°(0 K) = 122.75 ± 1.60 kcal/mol	Ruscic G4
0.052	6598.4	FCCF (g) → CCF (g) + F (g)	Δ_rH°(0 K) = 124.63 ± 1.60 kcal/mol	Ruscic CBS-n
0.045	6598.1	FCCF (g) → CCF (g) + F (g)	Δ_rH°(0 K) = 124.24 ± 1.72 kcal/mol	Ruscic G3X

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. 1.156 of the Thermochemical Network (2024); available at ATcT.anl.gov
4		N. A. Seifert, B. Ruscic, R. Sivaramakrishnan, and K. Prozument, The C2H4O Isomers in the Oxidation of Ethylene J. Mol. Spectrosc. 398, 111847/1-8 (2023) [DOI: 10.1016/j.jms.2023.111847]
5		U. Jacovella, B. Ruscic, N. L. Chen, H.-L. Le, S. Boyé-Péronne, S. Hartweg, M. Roy-Chowdhury, G. A. Garcia, J.-C. Loison, and B. Gans, Refining Thermochemical Properties of CF, SiF, and Their Cations by Combining Photoelectron Spectroscopy, Quantum Chemical Calculations, and the Active Thermochemical Tables Approach Phys. Chem. Chem. Phys. 25, 30838-30847 (2023) [DOI: 10.1039/D3CP04244H]
6		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]
7		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] and Ruscic and Bross[7]).
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.