Methane, dibromo-

• Formula: CH₂Br₂
• Molecular weight: 173.835
• IUPAC Standard InChI: InChI=1S/CH2Br2/c2-1-3/h1H2 Copy

  
• IUPAC Standard InChIKey: FJBFPHVGVWTDIP-UHFFFAOYSA-N Copy
• CAS Registry Number: 74-95-3
• 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.
• Other names: Dibromomethane; Methylene bromide; Methylene dibromide; CH2Br2; Rcra waste number U068; UN 2664
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• Information on this page:
  • Phase change data
  • Henry's Law data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Condensed phase thermochemistry data
  • Reaction thermochemistry data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • 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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Phase change 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 compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
    P = vapor pressure (atm)
    T = temperature (K)

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Henry's Law 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 compiled by: Rolf Sander

Henry's Law constant (water solution)

k_H(T) = k°_H exp(d(ln(k_H))/d(1/T) ((1/T) - 1/(298.15 K)))
k°_H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(k_H))/d(1/T) = Temperature dependence constant (K)

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
LL - Sharon G. Lias and Joel F. Liebman
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

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

CHBr₂^- +  =

By formula: CHBr₂^- + H⁺ = CH₂Br₂

References

Go To: Top, Phase change data, Henry's Law data, 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.

Timmermans, 1952
Timmermans, J., Freezing points of organic compounds. VVI New determinations., Bull. Soc. Chim. Belg., 1952, 61, 393. [all data]

Timmermans, 1921
Timmermans, J., The Freezing Points of Organic Substances IV. New Exp. Determinations, Bull. Soc. Chim. Belg., 1921, 30, 62. [all data]

Majer and Svoboda, 1985
Majer, V.; Svoboda, V., Enthalpies of Vaporization of Organic Compounds: A Critical Review and Data Compilation, Blackwell Scientific Publications, Oxford, 1985, 300. [all data]

Laynez and Wadso, 1972
Laynez, J.; Wadso, I., Enthalpies of vaporization of organic compounds. IX. Some halogen substituted hydrocarbons and esters, Acta Chem. Scand., 1972, 26, 3148. [all data]

Laynez, Wadsö, et al., 1972
Laynez, José; Wadsö, Ingemar; Haug, Arne; Songstad, J.; Pilotti, Åke, Enthalpies of Vaporization of Organic Compounds. IX. Some Halogen Substituted Hydrocarbons and Esters., Acta Chem. Scand., 1972, 26, 3148-3152, https://doi.org/10.3891/acta.chem.scand.26-3148 . [all data]

Kudchadker, Kudchadker, et al., 1979
Kudchadker, A.P.; Kudchadker, S.A.; Shukla, R.P.; Patnaik, P.R., Vapor pressures and boiling points of selected halomethanes, J. Phys. Chem. Ref. Data, 1979, 8, 2, 499, https://doi.org/10.1063/1.555600 . [all data]

Stull, 1947
Stull, Daniel R., Vapor Pressure of Pure Substances. Organic and Inorganic Compounds, Ind. Eng. Chem., 1947, 39, 4, 517-540, https://doi.org/10.1021/ie50448a022 . [all data]

Ma, Liao, et al., 1993
Ma, Z.-X.; Liao, C.-L.; Ng, C.Y.; Ma, N.G.; Li, W.-K., Adiabatic ionization energy and electron affinity of CH₂Br, J. Chem. Phys., 1993, 99, 6470. [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]

Watanabe, Nakayama, et al., 1962
Watanabe, K.; Nakayama, T.; Mottl, J., Ionization potentials of some molecules, J. Quant. Spectry. Radiative Transfer, 1962, 2, 369. [all data]

Von Niessen, Asbrink, et al., 1982
Von Niessen, W.; Asbrink, L.; Bieri, G., 30.4 nm He(II) Photoelectron spectra of organic molecules. Part VI. Halogeno-compounds (C,H,X: X = Cl, Br, I), J. Electron Spectrosc. Relat. Phenom., 1982, 26, 173. [all data]

Wittel and Bock, 1974
Wittel, K.; Bock, H., Photoelektronenspekten und molekuleigenschaften. XXVII. Chlor- und bromathylene- beispiele fur anderungen in π- und σ-Systemen, Chem. Ber., 1974, 107, 317. [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]

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]

DeCorpo, Bafus, et al., 1971
DeCorpo, J.J.; Bafus, D.A.; Franklin, J.L., Enthalpies of formation of the monohalomethyl radicals from mass spectrometric studies of the dihalomethanes, J. Chem. Thermodyn., 1971, 3, 125. [all data]

Franklin and Haney, 1970
Franklin, J.L.; Haney, M.A., Energy distribution in ionic decomposition processes, Recent Developments in Mass Spectroscopy, ed. K. Ogata and T. Hayakawa Baltimore Univ. Park Press, Baltimore, MD, 1970, 909. [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]

Holmes, Lossing, et al., 1988
Holmes, J.L.; Lossing, F.P.; McFarlane, R.A., Stabilization energy and positional effects in halogen-substituted alkyl ions., Int. J. Mass Spectrom. Ion Phys., 1988, 86, 209. [all data]

Born, Ingemann, et al., 2000
Born, M.; Ingemann, S.; Nibbering, N.M.M., Thermochemical properties of halogen-substituted methanes, methyl radicals, and carbenes in the gas phase, Int. J. Mass Spectrom., 2000, 194, 2-3, 103-113, https://doi.org/10.1016/S1387-3806(99)00125-6 . [all data]

Notes

Go To: Top, Phase change data, Henry's Law data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  IE (evaluated)	Recommended ionization energy
  Tboil	Boiling point
  Tfus	Fusion (melting) point
  d(ln(kH))/d(1/T)	Temperature dependence parameter for Henry's Law constant
  k°H	Henry's Law constant at 298.15K
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization
  ΔvapH°	Enthalpy of vaporization at standard conditions

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