Methane, dibromo-

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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

Quantity Value Units Method Reference Comment
Tboil370. ± 1.KAVGN/AAverage of 6 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus220.45KN/ATimmermans, 1952Uncertainty assigned by TRC = 0.5 K; TRC
Tfus220.63KN/ATimmermans, 1921Uncertainty assigned by TRC = 0.2 K; TRC
Quantity Value Units Method Reference Comment
Δvap8.850kcal/molN/AMajer and Svoboda, 1985 
Δvap8.836 ± 0.024kcal/molCLaynez and Wadso, 1972ALS
Δvap8.84 ± 0.02kcal/molA,ELaynez, Wadsö, et al., 1972AC

Enthalpy of vaporization

ΔvapH (kcal/mol) Temperature (K) Method Reference Comment
7.868370.1N/AMajer and Svoboda, 1985 
8.72288.CKudchadker, Kudchadker, et al., 1979Based on data from 273. to 373. K.; AC
9.03253.N/AStull, 1947Based on data from 238. to 371. K.; AC

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
238.1 to 371.84.511631546.096-28.977Stull, 1947Coefficents calculated by NIST from author's data.

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


Reaction thermochemistry 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:
B - John E. Bartmess
MS - José A. Martinho Simões

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

CHBr2- + Hydrogen cation = Methane, dibromo-

By formula: CHBr2- + H+ = CH2Br2

Quantity Value Units Method Reference Comment
Δr369.0 ± 3.1kcal/molG+TSBorn, Ingemann, et al., 2000gas phase; B
Quantity Value Units Method Reference Comment
Δr361.3 ± 3.0kcal/molIMRBBorn, Ingemann, et al., 2000gas phase; B

C14H21MnO2 (solution) + Methane, dibromo- (solution) = C8H7Br2MnO2 (solution) + Heptane (solution)

By formula: C14H21MnO2 (solution) + CH2Br2 (solution) = C8H7Br2MnO2 (solution) + C7H16 (solution)

Quantity Value Units Method Reference Comment
Δr-12.2 ± 1.2kcal/molPACYang and Yang, 1992solvent: Heptane; MS

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

Quantity Value Units Method Reference Comment
IE (evaluated)10.41 ± 0.13eVN/AN/AL

Ionization energy determinations

IE (eV) Method Reference Comment
10.24 ± 0.02PIMa, Liao, et al., 1993LL
10.5 ± 0.1EIKaposi, Riedel, et al., 1976LLK
10.52 ± 0.05PITsai, Baer, et al., 1975LLK
10.49 ± 0.02PIWatanabe, Nakayama, et al., 1962RDSH
10.6PEVon Niessen, Asbrink, et al., 1982Vertical value; LBLHLM
9.78PEWittel and Bock, 1974Vertical value; LLK
10.61PEDixon, Murrell, et al., 1971Vertical value; LLK
10.61PEPotts, Lempka, et al., 1970Vertical value; RDSH

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
Br+15.5 ± 0.1CH2BrEIDeCorpo, Bafus, et al., 1971LLK
Br+16.0CH2BrEIFranklin and Haney, 1970RDSH
HBr+18.2 ± 0.2?EIKaposi, Riedel, et al., 1976LLK
Br2+20.7 ± 0.5?EIKaposi, Riedel, et al., 1976LLK
C+22.7 ± 0.5?EIKaposi, Riedel, et al., 1976LLK
C+24.52 ± 0.05?EIReed and Snedden, 1956RDSH
CBr+19.6 ± 0.3?EIKaposi, Riedel, et al., 1976LLK
CBr2+15.6 ± 0.5?EIKaposi, Riedel, et al., 1976LLK
CH+22.0 ± 0.5?EIKaposi, Riedel, et al., 1976LLK
CH+21.55 ± 0.05?EIReed and Snedden, 1956RDSH
CHBr+16.0 ± 0.5?EIKaposi, Riedel, et al., 1976LLK
CH2+17.1 ± 0.3?EIKaposi, Riedel, et al., 1976LLK
CH2Br+11.27BrPIMa, Liao, et al., 1993LL
CH2Br+11.29BrEIHolmes, Lossing, et al., 1988LL
CH2Br+11.1 ± 0.2BrEIKaposi, Riedel, et al., 1976LLK
CH2Br+11.35 ± 0.02BrPITsai, Baer, et al., 1975LLK
CH2Br+10.93 ± 0.04BrEIReed and Snedden, 1956RDSH

De-protonation reactions

CHBr2- + Hydrogen cation = Methane, dibromo-

By formula: CHBr2- + H+ = CH2Br2

Quantity Value Units Method Reference Comment
Δr369.0 ± 3.1kcal/molG+TSBorn, Ingemann, et al., 2000gas phase; B
Quantity Value Units Method Reference Comment
Δr361.3 ± 3.0kcal/molIMRBBorn, Ingemann, et al., 2000gas phase; B

References

Go To: Top, Phase change data, Reaction thermochemistry 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]

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]

Yang and Yang, 1992
Yang, P.-F.; Yang, K.G., J. Am. Chem. Soc., 1992, 114, 6937. [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]


Notes

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