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Gas phase ion energetics 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 evaluated as indicated in comments:
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
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 CH2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)10.396 ± 0.003eVN/AN/AL
Quantity Value Units Method Reference Comment
Deltaf(+) ion328. ± 3.kcal/molN/AN/A 
Quantity Value Units Method Reference Comment
DeltafH(+) ion,0K329. ± 3.kcal/molN/AN/A 

Electron affinity determinations

EA (eV) Method Reference Comment
0.6520 ± 0.0060LPESLeopold, Murray, et al., 1985Singlet-triplet splitting of CH2 = 9.0 kcal; B
<0.600 ± 0.030PDFeldman, Rackwitz, et al., 1977B
0.210 ± 0.015LPESEngelking, Corderman, et al., 1981Hot band problem; B
0.208 ± 0.031LPESZittel, Ellison, et al., 1976Hot band problem, singlet-triplet splitting = 19.5 kcal; B
>0.90 ± 0.40EIAEThynne and MacNiel, 1971From CH2=CH2; B

Ionization energy determinations

IE (eV) Method Reference Comment
10.35 ± 0.15EIReineke and Strein, 1976LLK
10.5 ± 0.2EINiehaus, 1967RDSH
10.396 ± 0.003SHerzberg, 1961RDSH

De-protonation reactions

CH- + Hydrogen cation = Methylene

By formula: CH- + H+ = CH2

Quantity Value Units Method Reference Comment
Deltar386.05 ± 0.44kcal/molD-EAKasdan, Herbst, et al., 1975gas phase; B
Quantity Value Units Method Reference Comment
Deltar379.29 ± 0.53kcal/molH-TSKasdan, Herbst, et al., 1975gas phase; B


Go To: Top, 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.

Leopold, Murray, et al., 1985
Leopold, D.G.; Murray, K.K.; Miller, A.E.S.; Lineberger, W.C., Methylene: A study of the X3B1 and the 1A1 states by photoelectron spectroscopy of CH2- and CD2-, J. Chem. Phys., 1985, 83, 4849. [all data]

Feldman, Rackwitz, et al., 1977
Feldman, D.; Rackwitz, R.; Kaiser, H.J.; Heincke, E., Photodetachment bei einigen neagtiven molekulionen: P2-, As2-, CH2-, CH3-, S3-, Z. Naturforsch. A:, 1977, 32, 600. [all data]

Engelking, Corderman, et al., 1981
Engelking, P.E.; Corderman, R.R.; Wenddoski, J.J.; Ellison, G.B.; O'Niel, V.S.; Lineberger, W.C., Laser photoelectron spectroscopy of CH2-, and the singlet-triplet splitting in methylene, J. Chem. Phys., 1981, 74, 5460. [all data]

Zittel, Ellison, et al., 1976
Zittel, P.F.; Ellison, G.B.; O'Neil, S.V.; Herbst, E.; Lineberger, W.C.; Reinhardt, W.P., Laser photoelectron spectrometry of CH2-. Singlet-triplet splitting and electron affinity of CH21, J. Am. Chem. Soc., 1976, 98, 3731. [all data]

Thynne and MacNiel, 1971
Thynne, J.C.J.; MacNiel, K.A.G., Negative ion formation by ethylene and 1,1-difluoroethylene, J. Phys. Chem., 1971, 75, 2584. [all data]

Reineke and Strein, 1976
Reineke, W.; Strein, K., Erzeugung eines methylenhaltigen Molekularstrahls durch Pyrolyse von Keten, Ber. Bunsen-Ges. Phys. Chem., 1976, 80, 343. [all data]

Niehaus, 1967
Niehaus, A., Anregung und Dissoziation von Molekulen beim Elektronenbeschuss. Messung der Bildungswahrscheinlichkeit fur neutrale Fragmente als Funktion der Elektronenenergie., Z. Naturforsch., 1967, 22a, 690. [all data]

Herzberg, 1961
Herzberg, G., The ionization potential of CH2, Can J. Phys., 1961, 39, 1511. [all data]

Kasdan, Herbst, et al., 1975
Kasdan, A.; Herbst, E.; Lineberger, W.C., Laser photoelectron spectrometry of CH2-, Chem. Phys. Lett., 1975, 31, 78. [all data]


Go To: Top, Gas phase ion energetics data, References