Ethynyl radical
- Formula: C2H
- Molecular weight: 25.0293
- IUPAC Standard InChIKey: XEHVFKKSDRMODV-UHFFFAOYSA-N
- CAS Registry Number: 2122-48-7
- Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
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Gas phase thermochemistry data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 114.00 | kcal/mol | Review | Chase, 1998 | Data last reviewed in March, 1967 |
ΔfH°gas | 133. ± 2. | kcal/mol | N/A | Tsang, 1996 | |
Quantity | Value | Units | Method | Reference | Comment |
S°gas,1 bar | 49.579 | cal/mol*K | Review | Chase, 1998 | Data last reviewed in March, 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 (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.
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Temperature (K) | 298. to 1200. | 1200. to 6000. |
---|---|---|
A | 7.984981 | 9.391062 |
B | 5.763220 | 3.183750 |
C | -1.577581 | -0.466626 |
D | 0.066662 | 0.020624 |
E | -0.062012 | 0.233796 |
F | 111.1690 | 110.9710 |
G | 57.24541 | 59.41561 |
H | 114.0000 | 114.0000 |
Reference | Chase, 1998 | Chase, 1998 |
Comment | Data last reviewed in March, 1967 | Data last reviewed in March, 1967 |
Reaction thermochemistry data
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Data compiled by: John E. Bartmess
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.
Individual Reactions
(C2H2- • 4294967295) + = C2H2-
By formula: (C2H2- • 4294967295C2H) + C2H = C2H2-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 78.5 ± 3.6 | kcal/mol | N/A | Ervin, Gronert, et al., 1990 | gas phase; Vinylidene neutral: ΔHf<=99±2 kcal, Kiefer, Sidhu, et al., 1989 |
ΔrH° | 44.6 ± 3.3 | kcal/mol | Ther | Guo and Grabowski, 1990 | gas phase; Between PhF, Me3P |
Ion clustering data
Go To: Top, Gas phase thermochemistry data, Reaction 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 by: John E. Bartmess
Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.
Clustering reactions
(C2H2- • 4294967295) + = C2H2-
By formula: (C2H2- • 4294967295C2H) + C2H = C2H2-
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 78.5 ± 3.6 | kcal/mol | N/A | Ervin, Gronert, et al., 1990 | gas phase; Vinylidene neutral: ΔHf<=99±2 kcal, Kiefer, Sidhu, et al., 1989 |
ΔrH° | 44.6 ± 3.3 | kcal/mol | Ther | Guo and Grabowski, 1990 | gas phase; Between PhF, Me3P |
References
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Ion clustering 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]
Tsang, 1996
Tsang, W.,
Heats of Formation of Organic Free Radicals by Kinetic Methods
in Energetics of Organic Free Radicals, Martinho Simoes, J.A.; Greenberg, A.; Liebman, J.F., eds., Blackie Academic and Professional, London, 1996, 22-58. [all data]
Ervin, Gronert, et al., 1990
Ervin, K.M.; Gronert, S.; Barlow, S.E.; Gilles, M.K.; Harrison, A.G.; Bierbaum, V.M.; DePuy, C.H.; Lin, W.C.,
Bonds Strengths of Ethylene and Acetylene,
J. Am. Chem. Soc., 1990, 112, 15, 5750, https://doi.org/10.1021/ja00171a013
. [all data]
Kiefer, Sidhu, et al., 1989
Kiefer, J.H.; Sidhu, S.S.; Kumaran, S.S.; Irdan, E.A.,
RRKM Model of C2H4 Dissociation: Heat of Formation of Vinylidene,
Chem. Phys. Lett., 1989, 159, 1, 32, https://doi.org/10.1016/S0009-2614(89)87448-2
. [all data]
Guo and Grabowski, 1990
Guo, Y.; Grabowski, J.J.,
Gas Phase Ion Chemistry of the Vinylidene Radical Anion and the Acidity of the Vinyl Radical,
Int. J. Mass Spectrom. Ion Proc., 1990, 97, 3, 253, https://doi.org/10.1016/0168-1176(90)85003-K
. [all data]
Notes
Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Ion clustering 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 ΔrH° Enthalpy of reaction at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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