Methane, iodo-
- Formula: CH3I
- Molecular weight: 141.9390
- IUPAC Standard InChIKey: INQOMBQAUSQDDS-UHFFFAOYSA-N
- 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:
- 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
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Gas phase thermochemistry data
Go To: Top, Condensed phase thermochemistry data, Phase change data, Vibrational and/or electronic energy levels, 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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
Quantity | Value | Units | Method | Reference | Comment |
---|---|---|---|---|---|
ΔfH°gas | 3.42 ± 0.34 | kcal/mol | Eqk | Golden, Walsh, et al., 1965 | Reanalyzed by Cox and Pilcher, 1970, Original value = 3.28 ± 0.16 kcal/mol |
ΔfH°gas | 3.50 ± 0.24 | kcal/mol | Eqk | Goy and Pritchard, 1965 | Reanalyzed by Cox and Pilcher, 1970, Original value = 3.40 ± 0.24 kcal/mol |
ΔfH°gas | 3.8 ± 0.3 | kcal/mol | Chyd | Carson, 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 |
---|---|---|---|---|---|
ΔfH°liquid | -3.3 ± 0.1 | kcal/mol | Ccr | Carson, Laye, et al., 1993 | ALS |
ΔfH°liquid | -2.9 ± 0.3 | kcal/mol | Chyd | Carson, Carter, et al., 1961 | ALS |
Quantity | Value | Units | Method | Reference | Comment |
ΔcH°liquid | -193.3 ± 0.07 | kcal/mol | Ccr | Carson, Laye, et al., 1993 | ALS |
Constant pressure heat capacity of liquid
Cp,liquid (cal/mol*K) | Temperature (K) | Reference | Comment |
---|---|---|---|
19.78 | 298.15 | Carson, Laye, et al., 1993 | DH |
19.6 | 298.15 | Shehatta, 1993 | DH |
19.78 | 298.2 | Low and Moelwyn-Hughes, 1962 | T = 293 to 308 K.; DH |
19.76 | 300. | Harrison and Moelwyn-Hughes, 1957 | T = 243 to 303 K.; DH |
35.40 | 298. | Kurbatov, 1948 | T = -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 |
---|---|---|---|---|---|
Tboil | 315.7 ± 0.2 | K | AVG | N/A | Average of 7 values; Individual data points |
Quantity | Value | Units | Method | Reference | Comment |
Tfus | 206.7 | K | N/A | Timmermans, 1952 | Uncertainty assigned by TRC = 0.5 K; TRC |
Tfus | 208.1 | K | N/A | Timmermans, 1911 | Uncertainty assigned by TRC = 0.4 K; TRC |
Enthalpy of vaporization
ΔvapH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
7.27 | 243. | A | Stephenson and Malanowski, 1987 | Based on data from 228. to 337. K.; AC |
6.33 | 330. | A | Stephenson and Malanowski, 1987 | Based on data from 315. to 502. K.; AC |
7.43 | 217. | N/A | Wren and Vikis, 1982 | Based on data from 208. to 227. K.; AC |
6.98 | 274. | EB | Boublík and Aim, 1972 | Based on data from 259. to 314. K. See also Kudchadker, Kudchadker, et al., 1979.; AC |
7.27 | 233. | N/A | Stull, 1947 | Based on data from 218. to 315. K.; AC |
6.74 | 288. | N/A | Ewert, 1936 | Based on data from 273. to 307. K.; AC |
6.790 | 315.8 | V | Thompson and Linnett, 1936 | ALS |
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 315.6 | 4.1497 | 1177.78 | -32.058 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
315.6 to 521. | 4.14326 | 1223.831 | -20.179 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
273.3 to 307.6 | 5.13710 | 1755.986 | 26.111 | Thompson and Linnett, 1936 | Coefficents calculated by NIST from author's data. |
Enthalpy of sublimation
ΔsubH (kcal/mol) | Temperature (K) | Method | Reference | Comment |
---|---|---|---|---|
9.61 ± 0.1 | 191. | VG | Wren and Vikis, 1982 | Based on data from 176. to 227. K.; AC |
Enthalpy of fusion
ΔfusH (kcal/mol) | Temperature (K) | Reference | Comment |
---|---|---|---|
2.18 | 206.8 | Wren and Vikis, 1982 | AC |
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: C3ν Symmetry Number σ = 3
Sym. | No | Approximate | Selected Freq. | Infrared | Raman | Comments | ||||
---|---|---|---|---|---|---|---|---|---|---|
Species | type of mode | Value | Rating | Value | Phase | Value | Phase | |||
a1 | 1 | CH3 s-str | 2933 | E | 2969.8 M | gas | FR(2ν5) | |||
a1 | 1 | CH3 s-str | 2933 | E | 2861.0 M | gas | FR(2ν5) | |||
a1 | 2 | CH3 s-deform | 1252 | A | 1251.5 S | gas | ||||
a1 | 3 | CI str | 533 | A | 532.8 S | gas | ||||
e | 4 | CH3 d-str | 3060 | A | 3060.06 S | gas | ||||
e | 5 | CH3 d-deform | 1436 | C | 1435.5 M | gas | FR(ν3+ν6) | |||
e | 6 | CH3 rock | 882 | A | 882.4 M | gas | ||||
Source: Shimanouchi, 1972
Notes
S | Strong |
M | Medium |
FR | Fermi resonance with an overtone or a combination tone indicated in the parentheses. |
A | 0~1 cm-1 uncertainty |
C | 3~6 cm-1 uncertainty |
E | 15~30 cm-1 uncertainty |
References
Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, 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]
Shimanouchi, 1972
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, Vibrational and/or electronic energy levels, References
- Symbols used in this document:
Cp,liquid Constant pressure heat capacity of liquid Tboil Boiling point Tfus Fusion (melting) point 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 ΔsubH Enthalpy of sublimation ΔvapH Enthalpy of vaporization - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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