Methane, iodo-

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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

Quantity Value Units Method Reference Comment
Δfgas14.3 ± 1.4kJ/molEqkGolden, Walsh, et al., 1965Reanalyzed by Cox and Pilcher, 1970, Original value = 13.7 ± 0.67 kJ/mol
Δfgas14.6 ± 1.0kJ/molEqkGoy and Pritchard, 1965Reanalyzed by Cox and Pilcher, 1970, Original value = 14.2 ± 1.0 kJ/mol
Δfgas16. ± 1.kJ/molChydCarson, Carter, et al., 1961 

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

Quantity Value Units Method Reference Comment
Δfliquid-13.6 ± 0.5kJ/molCcrCarson, Laye, et al., 1993ALS
Δfliquid-12. ± 1.kJ/molChydCarson, Carter, et al., 1961ALS
Quantity Value Units Method Reference Comment
Δcliquid-808.6 ± 0.3kJ/molCcrCarson, Laye, et al., 1993ALS

Constant pressure heat capacity of liquid

Cp,liquid (J/mol*K) Temperature (K) Reference Comment
82.75298.15Carson, Laye, et al., 1993DH
82.0298.15Shehatta, 1993DH
82.76298.2Low and Moelwyn-Hughes, 1962T = 293 to 308 K.; DH
82.68300.Harrison and Moelwyn-Hughes, 1957T = 243 to 303 K.; DH
148.1298.Kurbatov, 1948T = -56 to 35°C. Mean Cp five temperatures.; DH

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

Quantity Value Units Method Reference Comment
Tboil315.7 ± 0.2KAVGN/AAverage of 7 values; Individual data points
Quantity Value Units Method Reference Comment
Tfus206.7KN/ATimmermans, 1952Uncertainty assigned by TRC = 0.5 K; TRC
Tfus208.1KN/ATimmermans, 1911Uncertainty assigned by TRC = 0.4 K; TRC

Enthalpy of vaporization

ΔvapH (kJ/mol) Temperature (K) Method Reference Comment
30.4243.AStephenson and Malanowski, 1987Based on data from 228. to 337. K.; AC
26.5330.AStephenson and Malanowski, 1987Based on data from 315. to 502. K.; AC
31.1217.N/AWren and Vikis, 1982Based on data from 208. to 227. K.; AC
29.2274.EBBoublík and Aim, 1972Based on data from 259. to 314. K. See also Kudchadker, Kudchadker, et al., 1979.; AC
30.4233.N/AStull, 1947Based on data from 218. to 315. K.; AC
28.2288.N/AEwert, 1936Based on data from 273. to 307. K.; AC
28.41315.8VThompson and Linnett, 1936ALS

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
218. to 315.64.15541177.78-32.058Stull, 1947Coefficents calculated by NIST from author's data.
315.6 to 521.4.148971223.831-20.179Stull, 1947Coefficents calculated by NIST from author's data.
273.3 to 307.65.142811755.98626.111Thompson and Linnett, 1936Coefficents calculated by NIST from author's data.

Enthalpy of sublimation

ΔsubH (kJ/mol) Temperature (K) Method Reference Comment
40.2 ± 0.4191.VGWren and Vikis, 1982Based on data from 176. to 227. K.; AC

Enthalpy of fusion

ΔfusH (kJ/mol) Temperature (K) Reference Comment
9.12206.8Wren and Vikis, 1982AC

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

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change 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 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

Iodide + Methane, iodo- = (Iodide • Methane, iodo-)

By formula: I- + CH3I = (I- • CH3I)

Quantity Value Units Method Reference Comment
Δr35.7 ± 0.84kJ/molN/AVan Duzor, Wei, et al., 2010gas phase; B
Δr32.6 ± 0.84kJ/molTDAsHiraoka, Fujita, et al., 1905gas phase; B
Δr35.1 ± 2.1kJ/molN/AArnold, Neumark, et al., 1995gas phase; ZEKE data, shift relative to bare I-; B
Δr34.7 ± 2.1kJ/molPDisCyr, Bishea, et al., 1992gas phase; B
Δr38. ± 8.4kJ/molTDAsDougherty and Roberts, 1974gas phase; B,M
Quantity Value Units Method Reference Comment
Δr68.6J/mol*KHPMSDougherty and Roberts, 1974gas phase; M
Quantity Value Units Method Reference Comment
Δr11.4 ± 0.84kJ/molTDAsHiraoka, Fujita, et al., 1905gas phase; B
Δr17.2 ± 1.3kJ/molTDAsDougherty and Roberts, 1974gas phase; B

C6H7N+ + Methane, iodo- = (C6H7N+ • Methane, iodo-)

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

Quantity Value Units Method Reference Comment
Δr41.kJ/molPHPMSMeot-Ner (Mautner) and El-Shall, 1986gas phase; Entropy change calculated or estimated; M
Quantity Value Units Method Reference Comment
Δr75.J/mol*KN/AMeot-Ner (Mautner) and El-Shall, 1986gas phase; Entropy change calculated or estimated; M

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
18.299.PHPMSMeot-Ner (Mautner) and El-Shall, 1986gas phase; Entropy change calculated or estimated; M

Chlorine anion + Methane, iodo- = (Chlorine anion • Methane, iodo-)

By formula: Cl- + CH3I = (Cl- • CH3I)

Quantity Value Units Method Reference Comment
Δr41.0 ± 0.84kJ/molTDAsDougherty and Roberts, 1974gas phase; B,M
Quantity Value Units Method Reference Comment
Δr31.J/mol*KHPMSDougherty and Roberts, 1974gas phase; Entropy change is questionable; M
Quantity Value Units Method Reference Comment
Δr29. ± 5.4kJ/molTDAsDougherty and Roberts, 1974gas phase; B

Hydrogen iodide + Methane, iodo- = Methane + Iodine

By formula: HI + CH3I = CH4 + I2

Quantity Value Units Method Reference Comment
Δr-52.55 ± 0.54kJ/molEqkGolden, Walsh, et al., 1965gas phase; ALS
Δr-53.0 ± 0.2kJ/molEqkGoy and Pritchard, 1965gas phase; ALS
Δr-46.2 ± 5.6kJ/molCmNichol and Ubbelohde, 1952gas phase; ALS

C12H16Nb (cr) + 2Iodine (cr) = C10H10I2Nb (cr) + 2Methane, iodo- (l)

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

Quantity Value Units Method Reference Comment
Δr-242.3 ± 2.4kJ/molRSCDiogo, Simoni, et al., 1993The difference between the enthalpies of formation of Nb(Cp)2(I)2 and Nb(Cp)2(Me)2 is calculated as -215.1 ± 2.6 kJ/mol; MS

C14H22CoN5O4 (solution) + Iodine (solution) = C13H19CoIN5O4 (solution) + Methane, iodo- (solution)

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

Quantity Value Units Method Reference Comment
Δr-92.9 ± 2.5kJ/molRSCToscano, Seligson, et al., 1989solvent: Bromoform; The enthalpy of solution of Co(py)(dmg)2(Me)(cr) was measured as 10.9 kJ/mol Toscano, Seligson, et al., 1989; MS

CH3I2- + 2Methane, iodo- = C2H6I3-

By formula: CH3I2- + 2CH3I = C2H6I3-

Quantity Value Units Method Reference Comment
Δr29.3 ± 0.84kJ/molTDAsHiraoka, Fujita, et al., 1905gas phase; B
Quantity Value Units Method Reference Comment
Δr4.35 ± 0.84kJ/molTDAsHiraoka, Fujita, et al., 1905gas phase; B

magnesium (cr) + Methane, iodo- (solution) = CH3IMg (solution)

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

Quantity Value Units Method Reference Comment
Δr-273.6 ± 0.8kJ/molRSCCarson and Skinner, 1950solvent: Diethyl ether; It was assumed that MeI(l) has a negligible solution enthalpy in ether; MS

CH2I- + Hydrogen cation = Methane, iodo-

By formula: CH2I- + H+ = CH3I

Quantity Value Units Method Reference Comment
Δr1616. ± 21.kJ/molG+TSIngemann and Nibbering, 1985gas phase; B
Quantity Value Units Method Reference Comment
Δr1587. ± 20.kJ/molIMRBIngemann and Nibbering, 1985gas phase; B

Mercury, dimethyl- (l) + 2Iodine (cr) = 2Methane, iodo- (l) + Mercury diiodide (cr)

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

Quantity Value Units Method Reference Comment
Δr-184.5 ± 0.8kJ/molRSCHartley, Pritchard, et al., 1950Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970, 2.; MS

Gallium trimethyl (l) + 3Iodine (cr) = GaI3 (cr) + 3Methane, iodo- (l)

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

Quantity Value Units Method Reference Comment
Δr-200.0 ± 8.4kJ/molRSCFowell and Mortimer, 1958Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970, 2.; MS

Gallium trimethyl (l) + 2Iodine (cr) = CH3GaI2 (cr) + 2Methane, iodo- (l)

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

Quantity Value Units Method Reference Comment
Δr-158.6 ± 4.2kJ/molRSCFowell and Mortimer, 1958Please also see Pedley and Rylance, 1977 and Cox and Pilcher, 1970, 2.; MS

C16H34P2Ru (solution) + Methane, iodo- (solution) = C16H33IP2Ru (solution) + Methane (solution)

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

Quantity Value Units Method Reference Comment
Δr-188.3 ± 2.9kJ/molRSCLuo, Li, et al., 1995solvent: Tetrahydrofuran; MS

C22H36Zr (solution) + 2Iodine (solution) = C20H30I2Zr (solution) + 2Methane, iodo- (solution)

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

Quantity Value Units Method Reference Comment
Δr-292.9 ± 2.5kJ/molRSCSchock and Marks, 1988solvent: Toluene; MS

C8H5MoNaO3 (solution) + Methane, iodo- (l) = C9H8MoO3 (solution) + Sodium iodide (cr)

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

Quantity Value Units Method Reference Comment
Δr-32.2 ± 1.3kJ/molRSCNolan, López de la Vega, et al., 1986solvent: Tetrahydrofuran; MS

C12H16Zr (solution) + 2Iodine (solution) = C10H10I2Zr (solution) + 2Methane, iodo- (solution)

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

Quantity Value Units Method Reference Comment
Δr-291.2 ± 2.5kJ/molRSCSchock and Marks, 1988solvent: Toluene; MS

C22H36Hf (solution) + 2Iodine (solution) = C20H30HfI2 (solution) + 2Methane, iodo- (solution)

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

Quantity Value Units Method Reference Comment
Δr-265.3 ± 3.3kJ/molRSCSchock and Marks, 1988solvent: Toluene; MS

Hydrogen + 2Methane, iodo- = 2Methane + Iodine

By formula: H2 + 2CH3I = 2CH4 + I2

Quantity Value Units Method Reference Comment
Δr-126. ± 3.kJ/molChydCarson, Carter, et al., 1961liquid phase; solvent: Ether; ALS

Methane + Methane, diiodo- = 2Methane, iodo-

By formula: CH4 + CH2I2 = 2CH3I

Quantity Value Units Method Reference Comment
Δr-20. ± 4.2kJ/molEqkFuruyama, Golden, et al., 1968gas phase; ALS

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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]

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]

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]

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]

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
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]

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]

Hartley, Pritchard, et al., 1950
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]

Pedley and Rylance, 1977
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]

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

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

Schock and Marks, 1988
Schock, L.E.; Marks, T.J., J. Am. Chem. Soc., 1988, 110, 7701. [all data]

Nolan, López de la Vega, et al., 1986
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]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, References