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 Copy

  
• IUPAC Standard InChIKey: FFEARJCKVFRZRR-SCSAIBSYSA-N Copy
• CAS Registry Number: 63-68-3
• Chemical structure:
  This structure is also available as a 2d Mol file
• Stereoisomers:
  • Methionine
  • D-Methionine
  • DL-Methionine
• 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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• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
• Data at other public NIST sites:
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Gas phase thermochemistry data

Go To: Top, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, 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

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

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

Enthalpy of sublimation

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

Data compiled as indicated in comments:
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

Appearance energy determinations

Mass spectrum (electron ionization)

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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: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

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.

Data compiled by: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, Mass spectrum (electron ionization), UV/Visible spectrum, 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]

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]

Cannington and Ham, 1983
Cannington, P.H.; Ham, N.S., He(I) and He(II) photoelectron spectra of glycine and related molecules, J. Electron Spectrosc. Relat. Phenom., 1983, 32, 139. [all data]

Svec and Junk, 1967
Svec, H.J.; Junk, G.A., Electron-impact studies of substituted alkanes, J. Am. Chem. Soc., 1967, 89, 790. [all data]

Akopyan and Loginov, 1967
Akopyan, M.E.; Loginov, Yy.V., Mass-spectrometric study of the phoionization of free α-aminoacids, High Energy Chem., 1967, 1, 83, In original 97. [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:
  

  AE	Appearance energy
  ΔcH°solid	Enthalpy of combustion of solid at standard conditions
  ΔfH°gas	Enthalpy of formation of gas 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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