L-Methionine
- Formula: C5H11NO2S
- Molecular weight: 149.211
- IUPAC Standard InChI: InChI=1S/C5H11NO2S/c1-9-3-2-4(6)5(7)8/h4H,2-3,6H2,1H3,(H,7,8)/t4-/m1/s1
- IUPAC Standard InChIKey: FFEARJCKVFRZRR-SCSAIBSYSA-N
- CAS Registry Number: 63-68-3
- Chemical structure:
This structure is also available as a 2d Mol file - Stereoisomers:
- Other names: Methionine; Methionine, L-; γ-Methylthio-α-aminobutyric acid; Butanoic acid, 2-amino-4-(methylthio)-, (S)-; Cymethion; L-(-)-Methionine; Met; S-Methionine; 2-Amino-4-(methylthio)butyric acid; Butyric acid, 2-amino-4-(methylthio)-; L(-)-Amino-γ-methylthiobutyric acid; L-α-Amino-γ-methylmercaptobutyric acid; L-γ-Methylthio-α-aminobutyric acid; 2-Amino-4-methylthiobutanoic acid; Liquimeth; Acimethin; L-2-Amino-4-(methylthio)butyric acid; (S)-2-Amino-4-(methylthio)butanoic acid; h-Met-oh; L-Homocysteine, S-methyl-; NSC 22946; 2-Amino-4-methylthiobutanoic acid (S)-
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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 by: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔfH°solid | -577.5 ± 0.7 | kJ/mol | Ccr | Sabbah and Minadakis, 1981 | |
| Quantity | Value | Units | Method | Reference | Comment |
| ΔcH°solid | -3564.11 ± 0.61 | kJ/mol | Ccr | Sabbah and Minadakis, 1981 | |
| ΔcH°solid | -3176. ± 0.8 | kJ/mol | Ccb | Tsuzuki, Harper, et al., 1958 |
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:
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
AC - William E. Acree, Jr., James S. Chickos
| Quantity | Value | Units | Method | Reference | Comment |
|---|---|---|---|---|---|
| ΔsubH° | 164. ± 4. | kJ/mol | C | Sabbah and Minadakis, 1981 | ALS |
| ΔsubH° | 164. ± 4. | kJ/mol | C | Sabbah and Minadakis, 1981 | AC |
Enthalpy of sublimation
| ΔsubH (kJ/mol) | Temperature (K) | Method | Reference | Comment |
|---|---|---|---|---|
| 125. | 474. | A | Stephenson and Malanowski, 1987 | Based on data from 463. to 485. K.; AC |
| 125. ± 0.8 | 455. | V | Svec and Clyde, 1965 | ALS |
UV/Visible spectrum
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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Spectrum
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Additional Data
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| Source | Johnson, 1971 |
|---|---|
| Owner | INEP CP RAS, NIST OSRD Collection (C) 2007 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved. |
| Origin | INSTITUTE OF ENERGY PROBLEMS OF CHEMICAL PHYSICS, RAS |
| Source reference | RAS UV No. 19870 |
| Instrument | Unicam SP 500 |
| Boiling point | 283 dec. |
References
Go To: Top, Condensed phase thermochemistry data, Phase change data, UV/Visible spectrum, NIST Free Links, NIST Subscription Links, Notes
Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.
Sabbah and Minadakis, 1981
Sabbah, R.; Minadakis, C.,
Thermodynamique de substances soufrees. II. Etude thermochimique de la l-cysteine et de la l-methionine,
Thermochim. Acta, 1981, 43, 269-277. [all data]
Tsuzuki, Harper, et al., 1958
Tsuzuki, T.; Harper, D.O.; Hunt, H.,
Heats of combustion. VII. The heats of combustion of some amino acids,
J. Phys. Chem., 1958, 62, 1594-1595. [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]
Svec and Clyde, 1965
Svec, H.J.; Clyde, D.D.,
Vapor pressures of some α-amino acids,
J. Chem. Eng. Data, 1965, 10, 151. [all data]
Johnson, 1971
Johnson, E.A.,
UV atlas of organic compounds, 1971, 5, J2/4. [all data]
Notes
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- Symbols used in this document:
ΔcH°solid Enthalpy of combustion of solid at standard conditions ΔfH°solid Enthalpy of formation of solid at standard conditions ΔsubH Enthalpy of sublimation ΔsubH° Enthalpy of sublimation at standard conditions - Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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