Ethyne, difluoro-
- Formula: C2F2
- Molecular weight: 62.0182
- IUPAC Standard InChIKey: BWTZYYGAOGUPFQ-UHFFFAOYSA-N
- CAS Registry Number: 689-99-6
- Chemical structure:
This structure is also available as a 2d Mol file - Other names: Acetylene, difluoro-; Difluoroacetylene; FC≡CF; Difluoroethyne; C2F2
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Gas phase thermochemistry data
Go To: Top, Gas phase ion energetics data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 20.92 | kJ/mol | Review | Chase, 1998 | Data last reviewed in December, 1967 |
ΔfH°gas | -190. ± 30. | kJ/mol | Eqk | Ehlert, 1969 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 244.06 | J/mol*K | Review | Chase, 1998 | Data last reviewed in December, 1967 |
Gas Phase Heat Capacity (Shomate Equation)
Cp° = A + B*t + C*t2 + D*t3 +
E/t2
H° − H°298.15= A*t + B*t2/2 +
C*t3/3 + D*t4/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t2/2 + D*t3/3 −
E/(2*t2) + G
Cp = heat capacity (J/mol*K)
H° = standard enthalpy (kJ/mol)
S° = standard entropy (J/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 298. to 1200. | 1200. to 6000. |
---|---|---|
A | 38.31795 | 85.46531 |
B | 89.70831 | 0.982972 |
C | -65.98963 | -0.192525 |
D | 17.89903 | 0.013000 |
E | -0.244157 | -6.812054 |
F | 5.236527 | -21.55835 |
G | 265.0840 | 323.6060 |
H | 20.92004 | 20.92004 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in December, 1967 | Data last reviewed in December, 1967 |
Gas phase ion energetics data
Go To: Top, Gas phase thermochemistry data, References, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled as indicated in comments:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
View reactions leading to C2F2+ (ion structure unspecified)
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
11.18 | PE | Bieri, Schmelzer, et al., 1980 | LLK |
11.18 | PE | Bieri, Heilbronner, et al., 1977 | LLK |
11.4 ± 0.5 | EI | Ehlert, 1969, 2 | RDSH |
References
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Chase, 1998
Chase, M.W., Jr.,
NIST-JANAF Themochemical Tables, Fourth Edition,
J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [all data]
Ehlert, 1969
Ehlert, T.C.,
Bonding in C1 and C2 fluroides,
J. Phys. Chem., 1969, 73, 949-953. [all data]
Bieri, Schmelzer, et al., 1980
Bieri, G.; Schmelzer, A.; Asbrink, L.; Jonsson, M.,
Fluorine and the fluoroderivatives of acetylene and diacetylene studied by 30.4 nm He(II) photoelectron spectroscopy,
Chem. Phys., 1980, 49, 213. [all data]
Bieri, Heilbronner, et al., 1977
Bieri, G.; Heilbronner, E.; Stadelmann, J.-P.; Vogt, J.; von Niessen, W.,
Electronic states of difluoroacetylene, difluorodiacetylene, and perfluoropentadiyne-1,3 radical cations. A photoelectron spectroscopic investigation,
J. Am. Chem. Soc., 1977, 99, 6832. [all data]
Ehlert, 1969, 2
Ehlert, T.C.,
Bonding in C1 and C2 fluorides,
J. Phys. Chem., 1969, 73, 949. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Gas phase ion energetics data, References
- Symbols used in this document:
S°gas,1 bar Entropy of gas at standard conditions (1 bar) ΔfH°gas Enthalpy of formation of gas at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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