Methane, bromo-
- Formula: CH3Br
- Molecular weight: 94.939
- IUPAC Standard InChIKey: GZUXJHMPEANEGY-UHFFFAOYSA-N
- 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:
- 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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Gas phase ion energetics data
Go To: Top, Mass spectrum (electron ionization), Gas Chromatography, 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)
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
IE (evaluated) | 10.541 ± 0.003 | eV | N/A | N/A | L |
Quantity | Value | Units | Method | Reference | Comment |
Proton affinity (review) | 664.2 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Quantity | Value | Units | Method | Reference | Comment |
Gas basicity | 638.0 | kJ/mol | N/A | Hunter and Lias, 1998 | HL |
Ionization energy determinations
IE (eV) | Method | Reference | Comment |
---|---|---|---|
10.54 | S | Baig, Connerade, et al., 1982 | LBLHLM |
10.53 | PE | Kimura, Katsumata, et al., 1981 | LLK |
10.53 | EI | Holmes, Fingas, et al., 1981 | LLK |
10.5 ± 0.2 | EI | Kaposi, Riedel, et al., 1976 | LLK |
10.54 ± 0.01 | PI | Tsai, Baer, et al., 1975 | LLK |
10.5 ± 0.2 | EI | Kaposi, Riedel, et al., 1975 | LLK |
10.541 | S | Hochmann, Templet, et al., 1975 | LLK |
10.53 | PE | Ragle, Stenhouse, et al., 1970 | RDSH |
10.54 | PE | Potts, Lempka, et al., 1970 | RDSH |
10.53 ± 0.015 | PE | Hashmall and Heilbronner, 1970 | RDSH |
10.53 | PI | Krauss, Walker, et al., 1968 | RDSH |
10.528 ± 0.005 | PI | Nicholson, 1965 | RDSH |
10.53 ± 0.01 | PI | Watanabe, 1957 | RDSH |
10.53 ± 0.02 | EI | Frost and McDowell, 1957 | RDSH |
10.541 ± 0.003 | S | Price, 1936 | RDSH |
10.54 | PE | Andrews, Dyke, et al., 1984 | Vertical value; LBLHLM |
10.53 | PE | Utsunomiya, Kobayashi, et al., 1980 | Vertical value; LLK |
10.53 | PE | Uehara, Saito, et al., 1973 | Vertical value; LLK |
10.70 | PE | Dixon, Murrell, et al., 1971 | Vertical value; LLK |
Appearance energy determinations
De-protonation reactions
CH2Br- + =
By formula: CH2Br- + H+ = CH3Br
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔrH° | 1660. ± 10. | kJ/mol | Endo | Hierl, Henchman, et al., 1992 | gas phase; HO- + MeBr:6.0±2.3 kcal/mol endo. "Better than Ingemann and Nibbering, 19852" 2.0 kcal would not show barrier; B |
ΔrH° | 1650. ± 19. | kJ/mol | EIAE | Rogers, Simpson, et al., 2010 | gas phase; B |
ΔrH° | 1643. ± 13. | kJ/mol | G+TS | Ingemann and Nibbering, 1985, 2 | gas phase; B |
Quantity | Value | Units | Method | Reference | Comment |
ΔrG° | 1631. ± 14. | kJ/mol | H-TS | Hierl, Henchman, et al., 1992 | gas phase; HO- + MeBr:6.0±2.3 kcal/mol endo. "Better than Ingemann and Nibbering, 19852" 2.0 kcal would not show barrier; B |
ΔrG° | 1614. ± 13. | kJ/mol | IMRB | Ingemann and Nibbering, 1985, 2 | gas phase; B |
Mass spectrum (electron ionization)
Go To: Top, Gas phase ion energetics data, Gas Chromatography, 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
View image of digitized spectrum (can be printed in landscape orientation).
Due to licensing restrictions, this spectrum cannot be downloaded.
Owner | NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
---|---|
NIST MS number | 19630 |
Gas Chromatography
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 by: NIST Mass Spectrometry Data Center, William E. Wallace, director
Kovats' RI, non-polar column, isothermal
Column type | Active phase | Temperature (C) | I | Reference | Comment |
---|---|---|---|---|---|
Packed | Apiezon L | 130. | 429. | von Kováts, 1958 | Celite (40:60 Gewichtsverhaltnis) |
Packed | Apiezon L | 70. | 429. | von Kováts, 1958 | Celite (40:60 Gewichtsverhaltnis) |
Normal alkane RI, non-polar column, temperature ramp
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | BP-1 | 421. | Health Safety Executive, 2000 | 50. m/0.22 mm/0.75 μm, He, 5. K/min; Tstart: 50. C; Tend: 200. C |
Normal alkane RI, non-polar column, custom temperature program
Column type | Active phase | I | Reference | Comment |
---|---|---|---|---|
Capillary | SPB-1 | 414. | Flanagan, Streete, et al., 1997 | 60. m/0.53 mm/5. μm, He; Program: 40C(6min) => 5C/min => 80C => 10C/min => 200C |
Capillary | Polydimethyl siloxanes | 415. | Zenkevich and Chupalov, 1996 | Program: not specified |
Capillary | SPB-1 | 414. | Strete, Ruprah, et al., 1992 | 60. m/0.53 mm/5.0 μm, Helium; Program: 40 0C (6 min) 5 0C/min -> 80 0C 10 0C/min -> 200 0C |
Capillary | OV-1, SE-30, Methyl silicone, SP-2100, OV-101, DB-1, etc. | 420. | Waggott and Davies, 1984 | Hydrogen; Column length: 50. m; Column diameter: 0.32 mm; Program: not specified |
References
Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, 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]
von Kováts, 1958
von Kováts, E.,
206. Gas-chromatographische Charakterisierung organischer Verbindungen. Teil 1: Retentionsindices aliphatischer Halogenide, Alkohole, Aldehyde und Ketone,
Helv. Chim. Acta, 1958, 41, 7, 1915-1932, https://doi.org/10.1002/hlca.19580410703
. [all data]
Health Safety Executive, 2000
Health Safety Executive,
MDHS 96 Volatile organic compounds in air - Laboratory method using pumed solid sorbent tubes, solvent desorption and gas chromatography
in Methods for the Determination of Hazardous Substances (MDHS) guidance, Crown, Colegate, Norwich, 2000, 1-24, retrieved from http://www.hse.gov.uk/pubns/mdhs/pdfs/mdhs96.pdf. [all data]
Flanagan, Streete, et al., 1997
Flanagan, R.J.; Streete, P.J.; Ramsey, J.D.,
Volatile Substance Abuse, UNODC Technical Series, No 5, United Nations, Office on Drugs and Crime, Vienna International Centre, PO Box 500, A-1400 Vienna, Austria, 1997, 56, retrieved from http://www.odccp.org/pdf/technicalseries1997-01-011.pdf. [all data]
Zenkevich and Chupalov, 1996
Zenkevich, I.G.; Chupalov, A.A.,
New Possibilities of Chromato Mass Pectrometric Identification of Organic Compounds Using Increments of Gas Chromatographic Retention Indices of Molecular Structural Fragments,
Zh. Org. Khim. (Rus.), 1996, 32, 5, 656-666. [all data]
Strete, Ruprah, et al., 1992
Strete, P.J.; Ruprah, M.; Ramsey, J.D.; Flanagan, R.J.,
Detection and identification of volatile substances by headspace capillary gas chromatography to aid the diagnosis of acute poisoning,
Analyst, 1992, 117, 7, 1111-1127, https://doi.org/10.1039/an9921701111
. [all data]
Waggott and Davies, 1984
Waggott, A.; Davies, I.W.,
Identification of organic pollutants using linear temperature programmed retention indices (LTPRIs) - Part II, 1984, retrieved from http://dwi.defra.gov.uk/research/completed-research/reports/dwi0383.pdf. [all data]
Notes
Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), Gas Chromatography, 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 - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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