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
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • Vibrational and/or electronic energy levels
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
  • Ion clustering data
  • 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

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
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

Enthalpy of vaporization

Antoine Equation Parameters

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

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Enthalpy of sublimation

Enthalpy of fusion

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

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)

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• GAS (200 mmHg DILUTED TO A TOTAL PRESSURE OF 600 mmHg WITH N2); DOW KBr FOREPRISM; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution
• LIQUID; Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

• gas

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

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

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, 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]

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]

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

Timmermans, 1911
Timmermans, J., Researches on the freezing point of organic liquid compounds, Bull. Soc. Chim. Belg., 1911, 25, 300. [all data]

Stephenson and Malanowski, 1987
Stephenson, Richard M.; Malanowski, Stanislaw, Handbook of the Thermodynamics of Organic Compounds, 1987, https://doi.org/10.1007/978-94-009-3173-2 . [all data]

Wren and Vikis, 1982
Wren, D.J.; Vikis, A.C., Vapour pressure of CH3I in the temperature range 176 to 227 K, The Journal of Chemical Thermodynamics, 1982, 14, 5, 435-437, https://doi.org/10.1016/0021-9614(82)90135-5 . [all data]

Boublík and Aim, 1972
Boublík, T.; Aim, K., Heats of vaporization of simple non-spherical molecule compounds, Collect. Czech. Chem. Commun., 1972, 37, 11, 3513-3521, https://doi.org/10.1135/cccc19723513 . [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]

Ewert, 1936
Ewert, M., Bull. Soc. Chim. Belg., 1936, 45, 493. [all data]

Thompson and Linnett, 1936
Thompson, H.W.; Linnett, J.W., The vapour pressures and association of some metallic and non-metallic alkyls, Trans. Faraday Soc., 1936, 32, 681-685. [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]

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]

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]

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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) 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]

Nichol and Ubbelohde, 1952
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]

Diogo, Simoni, et al., 1993
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Toscano, Seligson, et al., 1989
Toscano, P.J.; Seligson, A.L.; Curran, M.T.; Skrobutt, A.T.; Sonnenberger, D.C., Inorg. Chem., 1989, 28, 166; ibid. 1989. [all data]

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

Ingemann and Nibbering, 1985
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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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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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]

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

Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Henry's Law data, IR Spectrum, Mass spectrum (electron ionization), Vibrational and/or electronic energy levels, References

• Symbols used in this document:
  

  Cp,liquid	Constant pressure heat capacity of liquid
  T	Temperature
  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
  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
  ΔfusH	Enthalpy of fusion
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔrS°	Entropy of reaction at standard conditions
  ΔsubH	Enthalpy of sublimation
  ΔvapH	Enthalpy of vaporization

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