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Ethynyl radical

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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
Deltafgas476.98kJ/molReviewChase, 1998Data last reviewed in March, 1967
Deltafgas556. ± 8.kJ/molN/ATsang, 1996 
Quantity Value Units Method Reference Comment
gas,1 bar207.44J/mol*KReviewChase, 1998Data 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 (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. - 1200.1200. - 6000.
A 33.4091639.29220
B 24.1133113.32081
C -6.600595-1.952364
D 0.2789120.086290
E -0.2594590.978203
F 465.1311464.3027
G 239.5148248.5949
H 476.9760476.9760
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in March, 1967 Data last reviewed in March, 1967

Reaction thermochemistry 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 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- bullet 4294967295Ethynyl radical) + Ethynyl radical = C2H2-

By formula: (C2H2- bullet 4294967295C2H) + C2H = C2H2-

Quantity Value Units Method Reference Comment
Deltar328. ± 15.kJ/molN/AErvin, Gronert, et al., 1990gas phase; Vinylidene neutral: «DELTA»Hf<=99±2 kcal, Kiefer, Sidhu, et al., 1989
Deltar187. ± 14.kJ/molTherGuo and Grabowski, 1990gas phase; Between PhF, Me3P

References

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry 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, References