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 ion energetics data
  • Ion clustering data
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Henry's Law data
  • IR Spectrum
  • 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 ion energetics data

Go To: Top, Ion clustering data, Mass spectrum (electron ionization), References, Notes

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

Ion clustering data

Go To: Top, Gas phase ion energetics data, Mass spectrum (electron ionization), References, Notes

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)

Mass spectrum (electron ionization)

Go To: Top, Gas phase ion energetics data, Ion clustering data, References, Notes

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

References

Go To: Top, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Notes

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

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]

Kim, Kelley, et al., 1999
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]

Moutinho, Aten, et al., 1974
Moutinho, A.M.C.; Aten, J.A.; Los, J., Chemi-ionization in alkali-methylhalogen collisions, Chem. Phys., 1974, 5, 84. [all data]

Holmes and Lossing, 1991
Holmes, J.L.; Lossing, F.P., Ionization energies of homologous organic compounds and correlation with molecular size, Org. Mass Spectrom., 1991, 26, 537. [all data]

Carlson, Gerard, et al., 1988
Carlson, T.A.; Gerard, P.; Pullen, B.P.; Grimm, F.A., Autoionization from the ione-pair orbitals of molecules containing iodine, J. Chem. Phys., 1988, 89, 1464. [all data]

Baig, Connerade, et al., 1982
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]

Kimura, Katsumata, et al., 1981
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]

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

Mintz and Baer, 1976
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]

Hochmann, Templet, et al., 1975
Hochmann, P.; Templet, P.H.; Wang, H.-t.; McGlynn, S.P., Molecular Rydberg transitions. I. Low-energy Rydberg transitions in methyl halides, J. Chem. Phys., 1975, 62, 2588. [all data]

Boschi and Salahub, 1974
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]

Johnstone and Mellon, 1972
Johnstone, R.A.W.; Mellon, F.A., Electron-impact ionization and appearance potentials, J. Chem. Soc. Faraday Trans. 2, 1972, 68, 1209. [all data]

Boschi and Salahub, 1972
Boschi, R.A.; Salahub, D.R., The far ultra-violet spectra of some 1-iodoalkanes, Mol. Phys., 1972, 24, 289. [all data]

Brogli and Heilbronner, 1971
Brogli, F.; Heilbronner, E., The competition between spin orbit coupling and conjugation in alkyl halides and its repercussion on their photoelectron spectra, Helv. Chim. Acta, 1971, 54, 1423. [all data]

Ragle, Stenhouse, et al., 1970
Ragle, J.L.; Stenhouse, I.A.; Frost, D.C.; McDowell, C.A., Valence-shell ionization potentials of halomethanes by photoelectron spectroscopy. I. CH₃Cl, CH₃Br, CH₃I. Vibrational frequencies and vibronic interaction in CH₃Br⁺ and CH₃Cl⁺, J. Chem. Phys., 1970, 53, 178. [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]

Baer, Peatman, et al., 1969
Baer, T.; Peatman, W.B.; Schlag, E.W., Photoionization resonance studies with a steradiancy analyzer. II.The photoionization of CH₃I, Chem. Phys. Lett., 1969, 4, 243. [all data]

Price, 1936
Price, W.C., The far ultraviolet absorption spectra and ionization potentials of the alkyl halides. Part I, J. Chem. Phys., 1936, 4, 539. [all data]

Utsunomiya, Kobayashi, et al., 1980
Utsunomiya, C.; Kobayashi, T.; Nagakura, S., Photoelectron angular distribution measurements for some aliphatic alcohols, amines, halides, Bull. Chem. Soc. Jpn., 1980, 53, 1216. [all data]

Dromey and Peel, 1974
Dromey, R.G.; Peel, J.B., Photoelectron spectroscopic correlation of the molecular orbitals of the alkanes and alkyl iodides, J. Mol. Struct., 1974, 23, 53. [all data]

Uehara, Saito, et al., 1973
Uehara, Y.; Saito, N.; Yonezawa, T., Ionization potentials of trifluoromethyl and methyl halides by photoelectron spectroscopy and calculations by extended Hucket and CNDO/2 methods, Chem. Lett., 1973, 495. [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]

Tsuda and Hamill, 1964
Tsuda, S.; Hamill, W.H., Structure in ionization efficiency curves near threshold from alkanes and alkyl halides, J. Chem. Phys., 1964, 41, 2713. [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]

Martin, Lampe, et al., 1966
Martin, R.H.; Lampe, F.W.; Taft, R.W., An electron-impact study of ionization and dissociation in methoxy- and halogen- substituted methanes, J. Am. Chem. Soc., 1966, 88, 1353. [all data]

Traeger and McLoughlin, 1981
Traeger, J.C.; McLoughlin, R.G., Absolute heats of formation for gas phase cations, J. Am. Chem. Soc., 1981, 103, 3647. [all data]

Nicholson, 1970
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]

Lossing and Semeluk, 1970
Lossing, F.P.; Semeluk, G.P., Free radicals by mass spectrometry. XLII.Ionization potentials and ionic heats of formation for C₁-C₄ alkyl radicals, Can. J. Chem., 1970, 48, 955. [all data]

Tsuda, Melton, et al., 1964
Tsuda, S.; Melton, C.E.; Hamill, W.H., Ionization- efficiency curves for molecular and fragment ions from methane and the methyl halides, J. Chem. Phys., 1964, 41, 689. [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]

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]

Notes

Go To: Top, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), References

• Symbols used in this document:
  

  AE	Appearance energy
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  T	Temperature
  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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