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
  The 3d structure may be viewed using Java or Javascript.
• 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
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Phase change data
  • Henry's Law data
  • Ion clustering 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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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

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
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
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

 +  = ( • )

By formula: I^- + CH₃I = (I^- • CH₃I)

C₆H₇N⁺ +  = (C₆H₇N⁺ • )

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

Free energy of reaction

 +  = ( • )

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

 +  =  + 

By formula: HI + CH₃I = CH₄ + I₂

C₁₂H₁₆Nb (cr) + 2 (cr) = C₁₀H₁₀I₂Nb (cr) + 2 (l)

By formula: C₁₂H₁₆Nb (cr) + 2I₂ (cr) = C₁₀H₁₀I₂Nb (cr) + 2CH₃I (l)

C₁₄H₂₂CoN₅O₄ (solution) +  (solution) = C₁₃H₁₉CoIN₅O₄ (solution) +  (solution)

By formula: C₁₄H₂₂CoN₅O₄ (solution) + I₂ (solution) = C₁₃H₁₉CoIN₅O₄ (solution) + CH₃I (solution)

CH₃I₂^- + 2 = C₂H₆I₃^-

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

 (cr) +  (solution) = CH₃IMg (solution)

By formula: Mg (cr) + CH₃I (solution) = CH₃IMg (solution)

CH₂I^- +  =

By formula: CH₂I^- + H⁺ = CH₃I

 (l) + 2 (cr) = 2 (l) +  (cr)

By formula: C₂H₆Hg (l) + 2I₂ (cr) = 2CH₃I (l) + HgI₂ (cr)

 (l) + 3 (cr) = GaI₃ (cr) + 3 (l)

By formula: C₃H₉Ga (l) + 3I₂ (cr) = GaI₃ (cr) + 3CH₃I (l)

 (l) + 2 (cr) = CH₃GaI₂ (cr) + 2 (l)

By formula: C₃H₉Ga (l) + 2I₂ (cr) = CH₃GaI₂ (cr) + 2CH₃I (l)

C₁₆H₃₄P₂Ru (solution) +  (solution) = C₁₆H₃₃IP₂Ru (solution) +  (solution)

By formula: C₁₆H₃₄P₂Ru (solution) + CH₃I (solution) = C₁₆H₃₃IP₂Ru (solution) + CH₄ (solution)

C₂₂H₃₆Zr (solution) + 2 (solution) = C₂₀H₃₀I₂Zr (solution) + 2 (solution)

By formula: C₂₂H₃₆Zr (solution) + 2I₂ (solution) = C₂₀H₃₀I₂Zr (solution) + 2CH₃I (solution)

C₈H₅MoNaO₃ (solution) +  (l) = C₉H₈MoO₃ (solution) +  (cr)

By formula: C₈H₅MoNaO₃ (solution) + CH₃I (l) = C₉H₈MoO₃ (solution) + INa (cr)

C₁₂H₁₆Zr (solution) + 2 (solution) = C₁₀H₁₀I₂Zr (solution) + 2 (solution)

By formula: C₁₂H₁₆Zr (solution) + 2I₂ (solution) = C₁₀H₁₀I₂Zr (solution) + 2CH₃I (solution)

C₂₂H₃₆Hf (solution) + 2 (solution) = C₂₀H₃₀HfI₂ (solution) + 2 (solution)

By formula: C₂₂H₃₆Hf (solution) + 2I₂ (solution) = C₂₀H₃₀HfI₂ (solution) + 2CH₃I (solution)

 + 2 = 2 + 

By formula: H₂ + 2CH₃I = 2CH₄ + I₂

 +  = 2

By formula: CH₄ + CH₂I₂ = 2CH₃I

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

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

CH₂I^- +  =

By formula: CH₂I^- + H⁺ = CH₃I

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry 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.

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]

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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]

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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]

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

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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]

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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]

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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]

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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]

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Nichol, R.J.; Ubbelohde, A.R., A thermochemical evaluation of bond strengths in some carbon compounds. part II. Bond strengths based on the reaction CH₃I + HI = CH₄ + I₂, J. Am. Chem. Soc., 1952, 415-421. [all data]

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Diogo, H.P.; Simoni, J.A.; Minas da Piedade, M.E.; Dias, A.R.; Martinho Simões, J.A., J. Am. Chem. Soc., 1993, 115, 2764. [all data]

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Toscano, P.J.; Seligson, A.L.; Curran, M.T.; Skrobutt, A.T.; Sonnenberger, D.C., Inorg. Chem., 1989, 28, 166; ibid. 1989. [all data]

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Carson, A.S.; Skinner, H.A., Nature, 1950, 165, 484. [all data]

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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]

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Hartley, K.; Pritchard, H.O.; Skinner, H.A., Thermochemistry of metallic alkyls. III.?mercury dimethyl and mercury methyl halides, Trans. Faraday Soc., 1950, 46, 1019, https://doi.org/10.1039/tf9504601019 . [all data]

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Pedley, J.B.; Rylance, J., Computer Analysed Thermochemical Data: Organic and Organometallic Compounds, University of Sussex, Brigton, 1977. [all data]

Cox and Pilcher, 1970, 2
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds in Academic Press, New York, 1970. [all data]

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Fowell, P.A.; Mortimer, C.T., J. Chem. Soc., 1958, 3734.. [all data]

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Luo, L.; Li, C.; Cucullu, M.E.; Nolan, S.P., Organometallics, 1995, 14, 1333. [all data]

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Nolan, S.P.; López de la Vega, R.; Hoff, C.D., J. Organometal. Chem., 1986, 315, 187. [all data]

Furuyama, Golden, et al., 1968
Furuyama, S.; Golden, D.M.; Benson, S.W., The thermochemistry of the gas-phase equilibrium 2CH₃I = CH₄ + CH₂i₂. The heat of formation of CH₂I₂, J. Phys. Chem., 1968, 72, 4713-4715. [all data]

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]

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Kim, J.; Kelley, J.A.; Ayotte, P.; Nielsen, S.B.; Weddle, G.H.; Johnson, M.A., Preparation and photoelectron spectrum of the CH3I- anion: Rare gas cluster mediated synthesis of an ion-radical complex, J. Am. Soc. Mass Spectrom., 1999, 10, 9, 810-814, https://doi.org/10.1016/S1044-0305(99)00057-4 . [all data]

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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]

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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]

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Lias, S.G.; Ausloos, P.J., eIonization energies of organic compounds by equilibrium measurements, J. Am. Chem. Soc., 1978, 100, 6027. [all data]

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Mintz, D.M.; Baer, T., Kinetic energy release distributions for the dissociation of internal energy selected CH₃I⁺ and CD₃I⁺ ions, J. Chem. Phys., 1976, 65, 2407. [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]

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Boschi, R.A.A.; Salahub, D.R., The high resolution photoelectron spectra of some iodoalkanes, iodocycloalkanes, iodoalkenes, and fluoroiodohydrocarbons, Can. J. Chem., 1974, 52, 1217. [all data]

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Nicholson, A.J.C., Determination of bond dissociation energies from photoionization efficiency curves in Recent Developments in Mass Spectrometroscopy, ed. K Ogata and T. Hayakawa, Univ. Park Press, Baltimore, MD, 1970, 745. [all data]

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Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, References

• Symbols used in this document:
  

  AE	Appearance energy
  Cp,liquid	Constant pressure heat capacity of liquid
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  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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