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
Δfgas3.42 ± 0.34kcal/molEqkGolden, Walsh, et al., 1965Reanalyzed by Cox and Pilcher, 1970, Original value = 3.28 ± 0.16 kcal/mol
Δfgas3.50 ± 0.24kcal/molEqkGoy and Pritchard, 1965Reanalyzed by Cox and Pilcher, 1970, Original value = 3.40 ± 0.24 kcal/mol
Δfgas3.8 ± 0.3kcal/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-3.3 ± 0.1kcal/molCcrCarson, Laye, et al., 1993ALS
Δfliquid-2.9 ± 0.3kcal/molChydCarson, Carter, et al., 1961ALS
Quantity Value Units Method Reference Comment
Δcliquid-193.3 ± 0.07kcal/molCcrCarson, Laye, et al., 1993ALS

Constant pressure heat capacity of liquid

Cp,liquid (cal/mol*K) Temperature (K) Reference Comment
19.78298.15Carson, Laye, et al., 1993DH
19.6298.15Shehatta, 1993DH
19.78298.2Low and Moelwyn-Hughes, 1962T = 293 to 308 K.; DH
19.76300.Harrison and Moelwyn-Hughes, 1957T = 243 to 303 K.; DH
35.40298.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 (kcal/mol) Temperature (K) Method Reference Comment
7.27243.AStephenson and Malanowski, 1987Based on data from 228. to 337. K.; AC
6.33330.AStephenson and Malanowski, 1987Based on data from 315. to 502. K.; AC
7.43217.N/AWren and Vikis, 1982Based on data from 208. to 227. K.; AC
6.98274.EBBoublík and Aim, 1972Based on data from 259. to 314. K. See also Kudchadker, Kudchadker, et al., 1979.; AC
7.27233.N/AStull, 1947Based on data from 218. to 315. K.; AC
6.74288.N/AEwert, 1936Based on data from 273. to 307. K.; AC
6.790315.8VThompson and Linnett, 1936ALS

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
218. to 315.64.14971177.78-32.058Stull, 1947Coefficents calculated by NIST from author's data.
315.6 to 521.4.143261223.831-20.179Stull, 1947Coefficents calculated by NIST from author's data.
273.3 to 307.65.137101755.98626.111Thompson and Linnett, 1936Coefficents calculated by NIST from author's data.

Enthalpy of sublimation

ΔsubH (kcal/mol) Temperature (K) Method Reference Comment
9.61 ± 0.1191.VGWren and Vikis, 1982Based on data from 176. to 227. K.; AC

Enthalpy of fusion

ΔfusH (kcal/mol) Temperature (K) Reference Comment
2.18206.8Wren 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:


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)

kH(T) = H exp(d(ln(kH))/d(1/T) ((1/T) - 1/(298.15 K)))
H = Henry's law constant for solubility in water at 298.15 K (mol/(kg*bar))
d(ln(kH))/d(1/T) = Temperature dependence constant (K)

H (mol/(kg*bar)) d(ln(kH))/d(1/T) (K) Method Reference Comment
0.144300.MN/A 
0.35 QN/A missing citation give several references for the Henry's law constants but don't assign them to specific species.
0.193800.MN/A 
0.18 VN/A 
0.17 CN/A 

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

Quantity Value Units Method Reference Comment
IE (evaluated)9.54 ± 0.02eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)165.3kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity159.1kcal/molN/AHunter and Lias, 1998HL

Electron affinity determinations

EA (eV) Method Reference Comment
0.110 ± 0.020LPESKim, Kelley, et al., 1999B
0.30 ± 0.20NBIEMoutinho, Aten, et al., 1974Stated electron affinity is the Vertical Detachment Energy; B

Ionization energy determinations

IE (eV) Method Reference Comment
9.54 ± 0.05EIHolmes and Lossing, 1991LL
9.54PECarlson, Gerard, et al., 1988LL
10.86SBaig, Connerade, et al., 1982LBLHLM
9.54PEKimura, Katsumata, et al., 1981LLK
9.538EQLias and Ausloos, 1978LLK
9.54PIPECOMintz and Baer, 1976LLK
9.53 ± 0.01PITsai, Baer, et al., 1975LLK
9.538SHochmann, Templet, et al., 1975LLK
9.54PEBoschi and Salahub, 1974LLK
9.48 ± 0.03EIJohnstone and Mellon, 1972LLK
9.538SBoschi and Salahub, 1972LLK
9.52PEBrogli and Heilbronner, 1971LLK
10.14PEBrogli and Heilbronner, 1971LLK
9.50PERagle, Stenhouse, et al., 1970RDSH
9.54PEPotts, Lempka, et al., 1970RDSH
9.534 ± 0.005TEBaer, Peatman, et al., 1969RDSH
9.538 ± 0.003SPrice, 1936RDSH
9.53PEUtsunomiya, Kobayashi, et al., 1980Vertical value; LLK
9.9PEDromey and Peel, 1974Vertical value; LLK
9.51PEUehara, Saito, et al., 1973Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
CH+21.2 ± 0.2?EIReed and Snedden, 1956RDSH
CH2+14.6 ± 0.2HIEITsuda and Hamill, 1964RDSH
CH2I+12.78HEIHolmes, Lossing, et al., 1988LL
CH2I+12.08 ± 0.09HEIMartin, Lampe, et al., 1966RDSH
CH3+12.18IPITraeger and McLoughlin, 1981LLK
CH3+12.24 ± 0.01IPIPECOMintz and Baer, 1976LLK
CH3+12.25 ± 0.03IPITsai, Baer, et al., 1975LLK
CH3+12.07 ± 0.07IEIJohnstone and Mellon, 1972LLK
CH3+12.260 ± 0.013IPINicholson, 1970RDSH
CH3+12.22IEILossing and Semeluk, 1970RDSH
I+12.9 ± 0.05CH3EITsuda, Melton, et al., 1964RDSH

De-protonation reactions

CH2I- + Hydrogen cation = Methane, iodo-

By formula: CH2I- + H+ = CH3I

Quantity Value Units Method Reference Comment
Δr386.3 ± 4.9kcal/molG+TSIngemann and Nibbering, 1985gas phase; B
Quantity Value Units Method Reference Comment
Δr379.4 ± 4.8kcal/molIMRBIngemann and Nibbering, 1985gas phase; B

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law 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]

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]

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]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Henry's Law data, Gas phase ion energetics data, References