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
View 3d structure (requires JavaScript / HTML 5) - 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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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 (kJ/mol) | Temperature (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 30.4 | 243. | A | Stephenson and Malanowski, 1987 | Based on data from 228. to 337. K.; AC |
| 26.5 | 330. | A | Stephenson and Malanowski, 1987 | Based on data from 315. to 502. K.; AC |
| 31.1 | 217. | N/A | Wren and Vikis, 1982 | Based on data from 208. to 227. K.; AC |
| 29.2 | 274. | EB | Boublík and Aim, 1972 | Based on data from 259. to 314. K. See also Kudchadker, Kudchadker, et al., 1979.; AC |
| 30.4 | 233. | N/A | Stull, 1947 | Based on data from 218. to 315. K.; AC |
| 28.2 | 288. | N/A | Ewert, 1936 | Based on data from 273. to 307. K.; AC |
| 28.41 | 315.8 | V | Thompson and Linnett, 1936 | ALS |
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 315.6 | 4.1554 | 1177.78 | -32.058 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
| 315.6 to 521. | 4.14897 | 1223.831 | -20.179 | Stull, 1947 | Coefficents calculated by NIST from author's data. |
| 273.3 to 307.6 | 5.14281 | 1755.986 | 26.111 | Thompson and Linnett, 1936 | Coefficents calculated by NIST from author's data. |
Enthalpy of sublimation
| ΔsubH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 40.2 ± 0.4 | 191. | VG | Wren and Vikis, 1982 | Based on data from 176. to 227. K.; AC |
Enthalpy of fusion
| ΔfusH (kJ/mol) | Temperature (K) | Reference | Comment |
|---|---|---|---|
| 9.12 | 206.8 | Wren and Vikis, 1982 | AC |
Ion clustering 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
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
By formula: CH3I2- + 2CH3I = C2H6I3-
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 29.3 ± 0.84 | kJ/mol | TDAs | Hiraoka, Fujita, et al., 1905 | gas phase; B |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 4.35 ± 0.84 | kJ/mol | TDAs | Hiraoka, Fujita, et al., 1905 | gas phase; B |
By formula: C6H7N+ + CH3I = (C6H7N+ • CH3I)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 41. | kJ/mol | PHPMS | Meot-Ner (Mautner) and El-Shall, 1986 | gas phase; Entropy change calculated or estimated; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 75. | J/mol*K | N/A | Meot-Ner (Mautner) and El-Shall, 1986 | gas phase; Entropy change calculated or estimated; M |
Free energy of reaction
| ΔrG° (kJ/mol) | T (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 18. | 299. | PHPMS | Meot-Ner (Mautner) and El-Shall, 1986 | gas phase; Entropy change calculated or estimated; M |
By formula: Cl- + CH3I = (Cl- • CH3I)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 41.0 ± 0.84 | kJ/mol | TDAs | Dougherty and Roberts, 1974 | gas phase; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 31. | J/mol*K | HPMS | Dougherty and Roberts, 1974 | gas phase; Entropy change is questionable; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 29. ± 5.4 | kJ/mol | TDAs | Dougherty and Roberts, 1974 | gas phase; B |
By formula: I- + CH3I = (I- • CH3I)
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔrH° | 35.7 ± 0.84 | kJ/mol | N/A | Van Duzor, Wei, et al., 2010 | gas phase; B |
| ΔrH° | 32.6 ± 0.84 | kJ/mol | TDAs | Hiraoka, Fujita, et al., 1905 | gas phase; B |
| ΔrH° | 35.1 ± 2.1 | kJ/mol | N/A | Arnold, Neumark, et al., 1995 | gas phase; ZEKE data, shift relative to bare I-; B |
| ΔrH° | 34.7 ± 2.1 | kJ/mol | PDis | Cyr, Bishea, et al., 1992 | gas phase; B |
| ΔrH° | 38. ± 8.4 | kJ/mol | TDAs | Dougherty and Roberts, 1974 | gas phase; B,M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrS° | 68.6 | J/mol*K | HPMS | Dougherty and Roberts, 1974 | gas phase; M |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔrG° | 11.4 ± 0.84 | kJ/mol | TDAs | Hiraoka, Fujita, et al., 1905 | gas phase; B |
| ΔrG° | 17.2 ± 1.3 | kJ/mol | TDAs | Dougherty and Roberts, 1974 | gas phase; B |
References
Go To: Top, Phase change data, Ion clustering data, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
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]
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, Phase change data, Ion clustering data, References
- Symbols used in this document:
T Temperature Tboil Boiling point Tfus Fusion (melting) point 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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