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CH2=C

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Gas phase ion energetics data

Go To: Top, Vibrational and/or electronic energy levels, NIST Free Links, 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: «DELTA»Hf<=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

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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: Marilyn E. Jacox

State:   ?


 Energy 
 (cm-1
 Med.   Transition   «lambda»min 
 (nm) 
 «lambda»max 
 (nm) 
 References

Tx = 72795 gas Laufer, 1980
Laufer, 1983
Fahr and Laufer, 1985

State:   ?


 Energy 
 (cm-1
 Med.   Transition   «lambda»min 
 (nm) 
 «lambda»max 
 (nm) 
 References

To = 63873 gas Laufer, 1980
Laufer, 1983
Fahr and Laufer, 1985

State:   b


 Energy 
 (cm-1
 Med.   Transition   «lambda»min 
 (nm) 
 «lambda»max 
 (nm) 
 References

To = 22200 ± 160 gas Ervin, Ho, et al., 1989

State:   a


 Energy 
 (cm-1
 Med.   Transition   «lambda»min 
 (nm) 
 «lambda»max 
 (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, NIST Free Links, 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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