Methylene

• Formula: CH₂
• Molecular weight: 14.0266
• IUPAC Standard InChI: InChI=1S/CH2/h1H2 Copy

  
• IUPAC Standard InChIKey: HZVOZRGWRWCICA-UHFFFAOYSA-N Copy
• CAS Registry Number: 2465-56-7
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Isotopologues:
  • CD2
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• Information on this page:
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Reaction thermochemistry data
  • Ion clustering data
  • Vibrational and/or electronic energy levels
• Data at other public NIST sites:
  • Microwave spectra (on physics lab web site)
  • Electron-Impact Ionization Cross Sections (on physics web site)
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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)

Electron affinity determinations

Ionization energy determinations

De-protonation reactions

CH^- +  =

By formula: CH^- + H⁺ = CH₂

References

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]

Notes

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

• Symbols used in this document:
  

  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  ΔfH(+) ion,0K	Enthalpy of formation of positive ion at 0K
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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