Methane, iodo-

• Formula: CH₃I
• Molecular weight: 141.9390
• IUPAC Standard InChI: InChI=1S/CH3I/c1-2/h1H3 Copy

  
• IUPAC Standard InChIKey: INQOMBQAUSQDDS-UHFFFAOYSA-N Copy
• CAS Registry Number: 74-88-4
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Isotopologues:
  • iodo(2H3)methane
• Other names: Iodomethane; Methyl iodide; CH3I; Halon 10001; Iodometano; Iodure de methyle; Jod-methan; Joodmethaan; Methyljodid; Methyljodide; Metylu jodek; Monoioduro di metile; Rcra waste number U138; UN 2644; Methyl iodine; Monoiodomethane; NSC 9366
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Ion clustering data
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • 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 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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Condensed phase 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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Constant pressure heat capacity of liquid

Ion clustering 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
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

CH₃I₂^- + 2 = C₂H₆I₃^-

By formula: CH₃I₂^- + 2CH₃I = C₂H₆I₃^-

C₆H₇N⁺ +  = (C₆H₇N⁺ • )

By formula: C₆H₇N⁺ + CH₃I = (C₆H₇N⁺ • CH₃I)

Free energy of reaction

 +  = ( • )

By formula: Cl^- + CH₃I = (Cl^- • CH₃I)

 +  = ( • )

By formula: I^- + CH₃I = (I^- • CH₃I)

Vibrational and/or electronic energy levels

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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: Takehiko Shimanouchi

Symmetry:   C_3ν     Symmetry Number σ = 3

Source: Shimanouchi, 1972

Notes

References

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

Golden, Walsh, et al., 1965
Golden, D.M.; Walsh, R.; Benson, S.W., The thermochemistry of the gas phase equilibrium I₂ + CH₄ «=» CH₃I + HI and the heat of formation of the methyl radical, J. Am. Chem. Soc., 1965, 87, 4053-4057. [all data]

Cox and Pilcher, 1970
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press, New York, 1970, 1-636. [all data]

Goy and Pritchard, 1965
Goy, C.A.; Pritchard, H.O., Kinetics and thermodynamics of the reaction between iodine and methane and the heat of formation of methyl iodide, J. Phys. Chem., 1965, 69, 3040-3041. [all data]

Carson, Carter, et al., 1961
Carson, A.S.; Carter, W.; Pedley, J.B., The thermochemistry of reductions caused by lithium aluminium hydride I. The C-I bond dissociation energy in CH₃I, Proc. Roy. Soc. London A, 1961, 260, 550-557. [all data]

Carson, Laye, et al., 1993
Carson, A.S.; Laye, P.G.; Pedley, J.B.; Welsby, A.M., The enthalpies of formation iodomethane, diiodomethane, triiodomethane, and tetraiodomethane by rotating combustion calorimetry, J. Chem. Thermodyn., 1993, 25, 261-269. [all data]

Shehatta, 1993
Shehatta, I., Heat capacity at constant pressure of some halogen compounds, Thermochim. Acta, 1993, 213, 1-10. [all data]

Low and Moelwyn-Hughes, 1962
Low, D.I.R.; Moelwyn-Hughes, E.A., The heat capacities of acetone, methyl iodide and mixtures thereof in the liquid state, Proc. Roy. Soc. (London), 1962, A267, 384-394. [all data]

Harrison and Moelwyn-Hughes, 1957
Harrison, D.; Moelwyn-Hughes, E.A., The heat capacities of certain liquids, Proc. Roy. Soc. (London), 1957, A239, 230-246. [all data]

Kurbatov, 1948
Kurbatov, V.Ya., Heat capacity of liquids. 2. Heat capacity and the temperature dependence of heat capacity from halogen derivatives of acylic hydrocarbons, Zh. Obshch. Kim., 1948, 18, 372-389. [all data]

Hiraoka, Fujita, et al., 1905
Hiraoka, K.; Fujita, K.; Ishida, M.; Ichikawa, T.; Okada, H.; Hiizumi, K.; Wada, A.; Takao, K.; Yamabe, S.; Tsuchida, N., Gas-phase Ion/Molecule Reactions in C5F8, J. Phys. Chem. A (2005), 1905, 109, 6, 1049-1056., https://doi.org/10.1021/jp040251k . [all data]

Meot-Ner (Mautner) and El-Shall, 1986
Meot-Ner (Mautner), M.; El-Shall, M.S., Ionic Charge Transfer Complexes. 1. Cationic Complexes with Delocalized and Partially Localized pi Systems, J. Am. Chem. Soc., 1986, 108, 15, 4386, https://doi.org/10.1021/ja00275a026 . [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]

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]

Arnold, Neumark, et al., 1995
Arnold, C.C.; Neumark, D.M.; Cyr, D.M.; Johnson, M.A., Negative ion zero electron kinetic energy spectroscopy of I-center dot CH3I, J. Phys. Chem., 1995, 99, 6, 1633, https://doi.org/10.1021/j100006a002 . [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]

Shimanouchi, 1972
Shimanouchi, T., Tables of Molecular Vibrational Frequencies Consolidated Volume I, National Bureau of Standards, 1972, 1-160. [all data]

Notes

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• Symbols used in this document:
  

  Cp,liquid	Constant pressure heat capacity of liquid
  T	Temperature
  ΔcH°liquid	Enthalpy of combustion of liquid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas at standard conditions
  ΔfH°liquid	Enthalpy of formation of liquid at standard conditions
  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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