CH2=C

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Gas phase ion energetics data

Go To: Top, Vibrational and/or electronic energy levels, 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

View reactions leading to C2H2+ (ion structure unspecified)

Electron affinity determinations

EA (eV) Method Reference Comment
0.484 ± 0.010LPESGerardi, Breen, et al., 2010 
0.4466 ± 0.0016LPESErvin, Gronert, et al., 1990Vinylidene neutral: ΔHf<=99±2 kcal, Kiefer, Sidhu, et al., 1989
0.48 ± 0.21D-EAGuo and Grabowski, 1990Between PhF, Me3P
0.4900 ± 0.0060LPESErvin, Ho, et al., 1989neutral triplet state 47.6 kcal/mol up
0.470 ± 0.020LPESBurnett, Stevens, et al., 1983 
<0.42996IMRBLindinger, Albritton, et al., 1975 

Vibrational and/or electronic energy levels

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 by: Marilyn E. Jacox

State:   ?
 Energy 
 (cm-1) 		  Med.   Transition   λmin 
 (nm) 		  λmax 
 (nm) 		  References
Tx = 72795 gas Laufer, 1980
Laufer, 1983
Fahr and Laufer, 1985

State:   ?
 Energy 
 (cm-1) 		  Med.   Transition   λmin 
 (nm) 		  λmax 
 (nm) 		  References
To = 63873 gas Laufer, 1980
Laufer, 1983
Fahr and Laufer, 1985

State:   b
 Energy 
 (cm-1) 		  Med.   Transition   λmin 
 (nm) 		  λmax 
 (nm) 		  References
To = 22200 ± 160 gas Ervin, Ho, et al., 1989

State:   a
 Energy 
 (cm-1) 		  Med.   Transition   λmin 
 (nm) 		  λmax 
 (nm) 		  References
To = 16660 ± 50 gas Ervin, Ho, et al., 1989
Vib. 
sym. 		  No.   Approximate 
 type of mode 		  cm-1   Med.   Method   References
a1 1 CH2 s-stretch 2930 ± 10 gas PE Ervin, Ho, et al., 1989
2 C=C stretch 1530 ± 70 gas PE Ervin, Ho, et al., 1989
3 CH2 scissors 1375 ± 10 gas PE Ervin, Ho, et al., 1989

State:   X

Vib. 
sym. 		  No.   Approximate 
 type of mode 		  cm-1   Med.   Method   References
a1 1 CH2 s-stretch 3025 ± 30 gas PE Ervin, Ho, et al., 1989
2 C=C stretch 1635 ± 10 gas PE Burnett, Stevens, et al., 1983
Ervin, Ho, et al., 1989
3 CH2 scissors 1165 ± 10 gas PE Burnett, Stevens, et al., 1983
Ervin, Ho, et al., 1989

Additional references: Jacox, 1994, page 137; Fahr and Laufer, 1986

Notes

oEnergy separation between the v = 0 levels of the excited and electronic ground states.
xEnergy separation between the band maximum of the excited electronic state and the v = 0 level of the ground state.

References

Go To: Top, Gas phase ion energetics data, Vibrational and/or electronic energy levels, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Gerardi, Breen, et al., 2010
Gerardi, H.K.; Breen, K.J.; Guasco, T.L.; Weddle, G.H.; Gardenier, G.H.; Laaser, J.E.; Johnson, M.A., Survey of Ar-Tagged Predissociation and Vibrationally Mediated Photodetachment Spectroscopies of the Vinylidene Anion, C2H2-, J. Phys. Chem. A, 2010, 114, 3, 1592-1601, https://doi.org/10.1021/jp9095419 . [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]

Ervin, Ho, et al., 1989
Ervin, K.M.; Ho, J.; Linberger, W.C., A Study of the Singlet and Triplet States of Vinylidene by Photoelectron Spectroscopy of H2C=C-, D2C=C-, and HDC=C-. Vinylidene-Acetylene Isomerization, J. Chem. Phys., 1989, 91, 10, 5974, https://doi.org/10.1063/1.457415 . [all data]

Burnett, Stevens, et al., 1983
Burnett, S.M.; Stevens, A.E.; Feigerle, C.S.; Lineberger, W.C., Observation of X1A1 vinylidene by photoelectron spectroscopy of the C2H2- anion, Chem. Phys. Lett., 1983, 100, 124. [all data]

Lindinger, Albritton, et al., 1975
Lindinger, W.; Albritton, A.L.; Fehsenfeld, F.C.; Ferguson, E.E., Reactions of O- with N2, N2O, SO2, NH3, CH4, C2H4, and C2H2- with O2 from 300K to relative kinetic energies of 2 eV, J. Chem. Phys., 1975, 63, 3238. [all data]

Laufer, 1980
Laufer, A.H., An excited state of acetylene: Photochemical and spectroscopic evidence, J. Chem. Phys., 1980, 73, 1, 49, https://doi.org/10.1063/1.439846 . [all data]

Laufer, 1983
Laufer, A.H., Quenching of triplet vinylidene radicals by helium, Chem. Phys. Lett., 1983, 94, 2, 240, https://doi.org/10.1016/0009-2614(83)87583-6 . [all data]

Fahr and Laufer, 1985
Fahr, A.; Laufer, A.H., Photodissociation of vinyl chloride: formation and kinetics of vinylidene H2CC(3B2), J. Phys. Chem., 1985, 89, 13, 2906, https://doi.org/10.1021/j100259a039 . [all data]

Jacox, 1994
Jacox, M.E., Vibrational and electronic energy levels of polyatomic transient molecules, American Chemical Society, Washington, DC, 1994, 464. [all data]

Fahr and Laufer, 1986
Fahr, A.; Laufer, A.H., Collisional quenching of excited vinylidene (3B2) radicals, J. Phys. Chem., 1986, 90, 21, 5064, https://doi.org/10.1021/j100412a037 . [all data]

Notes

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