Methane, bromo-

• Formula: CH₃Br
• Molecular weight: 94.939
• IUPAC Standard InChI: InChI=1S/CH3Br/c1-2/h1H3 Copy

  
• IUPAC Standard InChIKey: GZUXJHMPEANEGY-UHFFFAOYSA-N Copy
• CAS Registry Number: 74-83-9
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
  The 3d structure may be viewed using Java or Javascript.
• Isotopologues:
  • bromo(2H3)methane
• Other names: Bromomethane; Curafume; Embafume; Halon 1001; Haltox; Iscobrome; Methyl bromide; Monobromomethane; Terabol; CH3Br; Bercema; Brom-methan; Brom-O-gas; Brom-O-gaz; Bromometano; Bromure de methyle; Bromuro di metile; Broommethaan; Celfume; Dawson 100; Detia gas ex-M; Dowfume mc-2; Dowfume mc-33; Dowfume mc-2 soil fumigant; Edco; Fumigant-1; Kayafume; MBX; MeBr; Metafume; Methogas; Methylbromid; Metylu bromek; Pestmaster; Profume; R 40B1; Rcra waste number U029; Terr-O-gas 67; Terr-O-gas 100; UN 1062; Zytox; Brom-O-sol; Methybrom
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• Information on this page:
  • Gas phase ion energetics data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • UV/Visible spectrum
  • Vibrational and/or electronic energy levels
  • Gas Chromatography
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
  • X-ray Photoelectron Spectroscopy Database, version 5.0
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Gas phase ion energetics data

Go To: Top, Ion clustering data, Mass spectrum (electron ionization), References, Notes

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:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
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 CH₃Br⁺ (ion structure unspecified)

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

CH₂Br^- +  =

By formula: CH₂Br^- + H⁺ = CH₃Br

Ion clustering data

Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), References, Notes

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

Data compiled as indicated in comments:
B - John E. Bartmess
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

 +  = ( • )

By formula: Br^- + CH₃Br = (Br^- • CH₃Br)

 +  = ( • )

By formula: CH₃⁺ + CH₃Br = (CH₃⁺ • CH₃Br)

CH₆N⁺ +  = (CH₆N⁺ • )

By formula: CH₆N⁺ + CH₃Br = (CH₆N⁺ • CH₃Br)

 +  = ( • )

By formula: Cl^- + CH₃Br = (Cl^- • CH₃Br)

 +  = ( • )

By formula: I^- + CH₃Br = (I^- • CH₃Br)

Mass spectrum (electron ionization)

Go To: Top, Gas phase ion energetics data, Ion clustering 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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Notes

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

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Baig, Connerade, et al., 1982
Baig, M.A.; Connerade, J.P.; Hormes, J., Autoionisation resonances in the 4p(Π) spectrum of methyl bromide, J. Phys. B:, 1982, 15, 5. [all data]

Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Holmes, Fingas, et al., 1981
Holmes, J.L.; Fingas, M.; Lossing, F.P., Towards a general scheme for estimating the heats of formation of organic ions in the gas phase. Part I. Odd-electron cations, Can. J. Chem., 1981, 59, 80. [all data]

Kaposi, Riedel, et al., 1976
Kaposi, O.; Riedel, M.; Vass-Balthazar, K.; Sanchez, G.R.; Lelik, L., Mass-spectrometric determination of thermochemical data of CHBr₃ and CBr₄ by study of their electron impact and heterogeneous pyrolytic decompositions, Acta Chim. Acad. Sci. Hung., 1976, 89, 221. [all data]

Tsai, Baer, et al., 1975
Tsai, B.P.; Baer, T.; Werner, A.S.; Lin, S.F., A photoelectron-photoion coincidence study of the ionization and fragment appearance potentials of bromo- and iodomethanes, J. Phys. Chem., 1975, 79, 570. [all data]

Kaposi, Riedel, et al., 1975
Kaposi, O.; Riedel, M.; Sanchez, G.R., Mass-spectrometric study of electron-impact and heterogeneous pyrolytic decomposition of methyl bromide, Acta Chim. Acad. Sci. Hung., 1975, 85, 361. [all data]

Hochmann, Templet, et al., 1975
Hochmann, P.; Templet, P.H.; Wang, H.-t.; McGlynn, S.P., Molecular Rydberg transitions. I. Low-energy Rydberg transitions in methyl halides, J. Chem. Phys., 1975, 62, 2588. [all data]

Ragle, Stenhouse, et al., 1970
Ragle, J.L.; Stenhouse, I.A.; Frost, D.C.; McDowell, C.A., Valence-shell ionization potentials of halomethanes by photoelectron spectroscopy. I. CH₃Cl, CH₃Br, CH₃I. Vibrational frequencies and vibronic interaction in CH₃Br⁺ and CH₃Cl⁺, J. Chem. Phys., 1970, 53, 178. [all data]

Potts, Lempka, et al., 1970
Potts, A.W.; Lempka, H.J.; Streets, D.G.; Price, W.C., Photoelectron spectra of the halides of elements in groups III, IV, V and VI, Phil. Trans. Roy. Soc. (London), 1970, A268, 59. [all data]

Hashmall and Heilbronner, 1970
Hashmall, J.A.; Heilbronner, E., n-Ionization potentials of alkyl bromides, Angew. Chem. Intern. Ed., 1970, 9, 305. [all data]

Krauss, Walker, et al., 1968
Krauss, M.; Walker, J.A.; Dibeler, V.H., Mass spectrometric study of photoionization. X. Hydrogen chloride and methyl halides, J. Res. NBS, 1968, 72A, 281. [all data]

Nicholson, 1965
Nicholson, A.J.C., Photoionization-efficiency curves. II. False and genuine structure, J. Chem. Phys., 1965, 43, 1171. [all data]

Watanabe, 1957
Watanabe, K., Ionization potentials of some molecules, J. Chem. Phys., 1957, 26, 542. [all data]

Frost and McDowell, 1957
Frost, D.C.; McDowell, C.A., Studies of the ionization of molecules by electron impact. II. Excited states of the molecular ions of methane and the methyl halides, Proc. Roy. Soc. (London), 1957, A241, 194. [all data]

Price, 1936
Price, W.C., The far ultraviolet absorption spectra and ionization potentials of the alkyl halides. Part I, J. Chem. Phys., 1936, 4, 539. [all data]

Andrews, Dyke, et al., 1984
Andrews, L.; Dyke, J.M.; Jonathan, N.; Keddar, N.; orris, A., The first bands in the photoelectron spectra of the CH₂Br, CD₂Br, CHBr₂, and CH₂I free radicals, J. Phys. Chem., 1984, 88, 1950. [all data]

Utsunomiya, Kobayashi, et al., 1980
Utsunomiya, C.; Kobayashi, T.; Nagakura, S., Photoelectron angular distribution measurements for some aliphatic alcohols, amines, halides, Bull. Chem. Soc. Jpn., 1980, 53, 1216. [all data]

Uehara, Saito, et al., 1973
Uehara, Y.; Saito, N.; Yonezawa, T., Ionization potentials of trifluoromethyl and methyl halides by photoelectron spectroscopy and calculations by extended Hucket and CNDO/2 methods, Chem. Lett., 1973, 495. [all data]

Dixon, Murrell, et al., 1971
Dixon, R.N.; Murrell, J.N.; Narayan, B., The photoelectron spectra of the halomethanes, Mol. Phys., 1971, 20, 611. [all data]

Tsuda, Melton, et al., 1964
Tsuda, S.; Melton, C.E.; Hamill, W.H., Ionization- efficiency curves for molecular and fragment ions from methane and the methyl halides, J. Chem. Phys., 1964, 41, 689. [all data]

Reed and Snedden, 1956
Reed, R.I.; Snedden, W., Studies in electron impact methods. Part 6.-The formation of the methine and carbon ions, J. Chem. Soc. Faraday Trans., 1956, 55, 876. [all data]

Tsuda and Hamill, 1964
Tsuda, S.; Hamill, W.H., Structure in ionization efficiency curves near threshold from alkanes and alkyl halides, J. Chem. Phys., 1964, 41, 2713. [all data]

Martin, Lampe, et al., 1966
Martin, R.H.; Lampe, F.W.; Taft, R.W., An electron-impact study of ionization and dissociation in methoxy- and halogen- substituted methanes, J. Am. Chem. Soc., 1966, 88, 1353. [all data]

Traeger and McLoughlin, 1981
Traeger, J.C.; McLoughlin, R.G., Absolute heats of formation for gas phase cations, J. Am. Chem. Soc., 1981, 103, 3647. [all data]

Williams and Hamill, 1968
Williams, J.M.; Hamill, W.H., Ionization potentials of molecules and free radicals and appearance potentials by electron impact in the mass spectrometer, J. Chem. Phys., 1968, 49, 4467. [all data]

Hierl, Henchman, et al., 1992
Hierl, P.M.; Henchman, M.J.; Paulson, J.F., Threshold Energies for the Reactions HO- + MeX - MeOH + X- measured by Tandem Mass Spectrometry: Acidities of MeCl and MeBr, Int. J. Mass Spectrom. Ion Proc., 1992, 117, 475, https://doi.org/10.1016/0168-1176(92)80109-E . [all data]

Ingemann and Nibbering, 1985
Ingemann, S.; Nibbering, N.M.M., Gas phase chemistry of alpha-thio carbanions, Can. J. Chem., 1985, 62, 2273. [all data]

Rogers, Simpson, et al., 2010
Rogers, N.J.; Simpson, M.J.; Tuckett, R.P.; Dunn, K.F.; Latimer, C.J., Vacuum-UV negative photoion spectroscopy of CH3F, CH3Cl and CH3Br, Phys. Chem. Chem. Phys., 2010, 12, 36, 10971-10980, https://doi.org/10.1039/c0cp00234h . [all data]

Ingemann and Nibbering, 1985, 2
Ingemann, S.; Nibbering, N.M.M., Gas-phase acidity of CH₃X [X = P(CH₃)₂, SCH₃, F, Cl, Br, I] compounds, J. Chem. Soc. Perkin Trans. 2, 1985, 837. [all data]

Li, Ross, et al., 1996
Li, C.; Ross, P.; Szulejko, J.; McMahon, T.B., High-Pressure Mass Spectrometric Investigations of the Potential Energy Surfaces of Gas-Phase Sn2 Reactions., J. Am. Chem. Soc., 1996, 118, 39, 9360, https://doi.org/10.1021/ja960565o . [all data]

Dougherty and Roberts, 1974
Dougherty, R.C.; Roberts, J.D., SN₂ reactions in the gas phase. Nucleophilicity effects, Org. Mass Spectrom., 1974, 8, 81. [all data]

McMahon, Heinis, et al., 1988
McMahon, T.; Heinis, T.; Nicol, G.; Hovey, J.K.; Kebarle, P., Methyl Cation Affinities, J. Am. Chem. Soc., 1988, 110, 23, 7591, https://doi.org/10.1021/ja00231a002 . [all data]

Foster, Williamson, et al., 1974
Foster, M.S.; Williamson, A.D.; Beauchamp, J.L., Photoionization mass spectrometry of trans-azomethane, Int. J. Mass Spectrom. Ion Phys., 1974, 15, 429. [all data]

Meot-Ner, 1984
Meot-Ner, (Mautner)M., The Ionic Hydrogen Bond and Ion Solvation. 1. -NH+ O-, -NH+ N- and -OH+ O- Bonds. Correlations with Proton Affinity. Deviations Due to Structural Effects, J. Am. Chem. Soc., 1984, 106, 5, 1257, https://doi.org/10.1021/ja00317a015 . [all data]

Riveros, Breda, et al., 1973
Riveros, J.M.; Breda, A.C.; Blair, L.K., Formation and relative stability of chloride ion clusters in the gas phase by ICR spectroscopy, J. Am. Chem. Soc., 1973, 95, 4066. [all data]

Larson and McMahon, 1984
Larson, J.W.; McMahon, T.B., Fluoride and chloride affinities of main group oxides, fluorides, oxofluorides, and alkyls. Quantitative scales of lewis acidities from ion cyclotron resonance halide-exchange equilibria, J. Phys. Chem., 1984, 88, 1083. [all data]

Van Duzor, Wei, et al., 2010
Van Duzor, M.; Wei, J.; Mbaiwa, F.; Mabbs, R., I-center dot CH3X (X=Cl, Br, I) photodetachment: The effect of electron-molecule interactions in cluster anion photodetachment spectra and angular distributions, J. Chem. Phys., 2010, 133, 14, 144303, https://doi.org/10.1063/1.3487739 . [all data]

Cyr, Bishea, et al., 1992
Cyr, D.M.; Bishea, G.A.; Scarton, M.G.; Johnson, M.A., Observation of Charge-Transfer Excited States in the I-.CH3I, I-.CH3Br, and I-.CH2Br2 S(N)2 Reaction Intermediates Using Photofragmentation, J. Chem. Phys., 1992, 97, 8, 5911, https://doi.org/10.1063/1.463752 . [all data]

Notes

Go To: Top, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions

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