Alanine - The NIST WebBook

Alanine

• Formula: C3H7NO2
• Molecular weight: 89.0932
• IUPAC Standard InChI: InChI=1S/C3H7NO2/c1-2(4)3(5)6/h2H,4H2,1H3,(H,5,6)/t2-/m1/s1 Copy
• IUPAC Standard InChIKey: QNAYBMKLOCPYGJ-UWTATZPHSA-N Copy
• CAS Registry Number: 56-41-7
• 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)
• Stereoisomers:
  • dl-Alanine
  • D-Alanine
  • 2-aminopropanoic acid
• Other names: L-Alanine; Alanine, L-; α-Alanine; α-Aminopropionic acid; (S)-Alanine; L-α-Alanine; L-α-Aminopropionic acid; L-(+)-Alanine; L-2-Aminopropanoic acid; L-2-Aminopropionic acid; Propanoic acid, 2-amino-; Propanoic acid, 2-amino-, (S)-; L-CH3CH(NH2)COOH; (S)-2-Aminopropanoic acid; 2-Aminopropanoic acid; 2-Aminopropionic acid; Ala; Ritalanine; NSC 206315; 2-Aminopropanoic acid, L-
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Condensed phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Mass spectrum (electron ionization)
  • UV/Visible spectrum
  • References
  • Notes
• Other data available:
  • Gas phase ion energetics data
  • Ion clustering data
• Options:
  • Switch to SI units

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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
ΔfH°gas	-99.1 ± 1.0	kcal/mol	Ccr	Ngauv, Sabbah, et al., 1977

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°solid	-134. ± 0.41	kcal/mol	Ccb	Contineanu and Marchidan, 1984	ALS
ΔfH°solid	-133.72	kcal/mol	Ccr	Ngauv, Sabbah, et al., 1977	ALS
ΔfH°solid	-134.5	kcal/mol	Ccb	Hutchens, Cole, et al., 1963	Heat of combustion is not reported; ALS
Quantity	Value	Units	Method	Reference	Comment
ΔcH°solid	-387.4 ± 0.41	kcal/mol	Ccb	Contineanu and Marchidan, 1984	ALS
ΔcH°solid	-387.54 ± 0.11	kcal/mol	Ccr	Ngauv, Sabbah, et al., 1977	ALS
ΔcH°solid	-376.9 ± 0.5	kcal/mol	Ccb	Tsuzuki, Harper, et al., 1958	ALS
ΔcH°solid	-390.56	kcal/mol	Ccb	Lemoult, 1904	ALS
Quantity	Value	Units	Method	Reference	Comment
S°solid,1 bar	30.882	cal/mol*K	N/A	Hutchens, Cole, et al., 1960	DH
S°solid,1 bar	28.39	cal/mol*K	N/A	Daurel, Delhaes, et al., 1975	DH

Constant pressure heat capacity of solid

Cp,solid (cal/mol*K)	Temperature (K)	Reference	Comment
27.5	298.	Badelin, Kulikov, et al., 1990	T = 298, 313, 333, 348 K.; DH
27.53	298.	Kulikov, Kozlov, et al., 1989	T = 298 to 348 K.; DH
29.221	298.15	Hutchens, Cole, et al., 1960	T = 11 to 305 K.; 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: 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°	34.6 ± 1.0	kcal/mol	C	Ngauv, Sabbah, et al., 1977	ALS
ΔsubH°	34.6 ± 1.0	kcal/mol	N/A	Nguon Ngauv, Sabbah, et al., 1977	AC

Enthalpy of sublimation

ΔsubH (kcal/mol)	Temperature (K)	Method	Reference	Comment
31.7 ± 0.2	414.	TE,ME	de Kruif, Voogd, et al., 1979	AC
31.64 ± 0.31	433.	C	Nguon Ngauv, Sabbah, et al., 1977	Based on data from 413. to 450. K.; AC
33.0 ± 0.2	455.	V	Svec and Clyde, 1965	ALS

Reaction 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: B - John E. Bartmess RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

C3H6NO2- + =

By formula: C3H6NO2- + H+ = C3H7NO2

Quantity	Value	Units	Method	Reference	Comment
ΔrH°	341.8 ± 1.9	kcal/mol	CIDC	Jones, Bernier, et al., 2007	gas phase; B
ΔrH°	340.7 ± 2.1	kcal/mol	G+TS	Locke and McIver, 1983	gas phase; B
Quantity	Value	Units	Method	Reference	Comment
ΔrG°	334.8 ± 2.0	kcal/mol	H-TS	Jones, Bernier, et al., 2007	gas phase; B
ΔrG°	333.7 ± 2.0	kcal/mol	IMRE	Locke and McIver, 1983	gas phase; B

+ = ( • )

By formula: Na+ + C3H7NO2 = (Na+ • C3H7NO2)

Quantity	Value	Units	Method	Reference	Comment
ΔrH°	40.4 ± 3.0	kcal/mol	IMRE	Gapeev and Dunbar, 2003	Anchor glycine=38.5+-2.0; RCD
ΔrH°	39.9	kcal/mol	CIDC	Kish, Ohanessian, et al., 2003	Anchor alanine=39.89; RCD

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

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Owner	NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.
Origin	Japan AIST/NIMC Database- Spectrum MS-NW- 301
NIST MS number	228084

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UV/Visible spectrum

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Mass spectrum (electron ionization), 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: Victor Talrose, Alexander N. Yermakov, Alexy A. Usov, Antonina A. Goncharova, Axlexander N. Leskin, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

Notice: This spectrum may be better viewed with a Javascript and HTML 5 enabled browser.

For Zoom

1.) Enter the desired X axis range (e.g., 100, 200)

2.) Check here for automatic Y scaling

3.) Press here to zoom

• Plot
• Help / Software credits

Help

The interactive spectrum display requires a browser with JavaScript and HTML 5 canvas support.

Select a region with data to zoom. Select a region with no data or click the mouse on the plot to revert to the orginal display.

Credits

The following components were used in generating the plot:

• jQuery
• jQuery UI
• Flot
• Plugins for Flot:
  • Resize (distributed with Flot)
  • Selection (distributed with Flot)
  • Axis labels
  • Labels ( Modified by NIST for use in this application)

Additonal code used was developed at NIST: jcamp-dx.js and jcamp-plot.js.

Use or mention of technologies or programs in this web site is not intended to imply recommendation or endorsement by the National Institute of Standards and Technology, nor is it intended to imply that these items are necessarily the best available for the purpose.

Additional Data

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Source	Abu-Eittah, et al., 1988
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. 17326
Instrument	unknown
Melting point	300 dec.

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry 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.

Ngauv, Sabbah, et al., 1977 Ngauv, S.N.; Sabbah, R.; Laffitte, M., Thermodynamique de composes azotes. III. Etude thermochimique de la glycine et de la l-α-alanine, Thermochim. Acta, 1977, 20, 371-380. [all data]

Contineanu and Marchidan, 1984 Contineanu, I.; Marchidan, D.I., The enthalpies of combustion and formation of D-alanine, L-alanine, DL-alanine, and β-alanine, Rev. Roum. Chim., 1984, 29, 43-48. [all data]

Hutchens, Cole, et al., 1963 Hutchens, J.O.; Cole, A.G.; Stout, J.W., Heat capacities from 11 to 305°K., entropies, and free energies of formation of L-valine, L-isoleucine, and L-leucine, J. Phys. Chem., 1963, 67, 1128-1130. [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]

Lemoult, 1904 Lemoult, M.P., Remarques sur une serie recenie de determinations calorimetriques, Compt. Rend., 1904, 663-635. [all data]

Hutchens, Cole, et al., 1960 Hutchens, J.O.; Cole, A.G.; Stout, J.W., Heat capacities from 11 to 305K. and entropies of L-alanine and glycine, J. Am. Chem. Soc., 1960, 82, 4813-4815. [all data]

Daurel, Delhaes, et al., 1975 Daurel, M.; Delhaes, P.; Dupart, E., Variations thermiques, entre 1 et 300K, de la chaleur specifique de la L-alanine, tri(L-alanine) et de la poly(L-alanine), Biopolymers, 1975, 14, 801-823. [all data]

Badelin, Kulikov, et al., 1990 Badelin, V.G.; Kulikov, O.V.; Batagin, V.S.; Udzig, E.; Zielenkiewicz, A.; Zielenkiewicz, W.; Krestov, G.A., Physico-chemical properties of peptides and their solutions, Thermochim. Acta, 1990, 169, 81-93. [all data]

Kulikov, Kozlov, et al., 1989 Kulikov, O.V.; Kozlov, V.A.; Malenkina, L.I.; Badelin, V.G., Heat capacities of amino acids and peptides and excess characteristics ot their aqueous solutions, Sbornik Nauch. Trud., Termodin. Rast. neelect., Ivanovo, Inst. nevod. rast., 1989, Akad. [all data]

Nguon Ngauv, Sabbah, et al., 1977 Nguon Ngauv, Song; Sabbah, Raphael; Laffitie, Marc, Thermodynamique de composes azotes III. Etude Thermochimique de la glycine et de la l-α-alanine, Thermochimica Acta, 1977, 20, 3, 371-380, https://doi.org/10.1016/0040-6031(77)85091-0 . [all data]

de Kruif, Voogd, et al., 1979 de Kruif, C.G.; Voogd, J.; Offringa, J.C.A., Enthalpies of sublimation and vapour pressures of 14 amino acids and peptides, The Journal of Chemical Thermodynamics, 1979, 11, 7, 651-656, https://doi.org/10.1016/0021-9614(79)90030-2 . [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]

Jones, Bernier, et al., 2007 Jones, C.M.; Bernier, M.; Carson, E.; Colyer, K.E.; Metz, R.; Pawlow, A.; Wischow, E.D.; Webb, I.; Andriole, E.J.; Poutsma, J.C., Gas-phase Acities of the 20 Protein Amino Acids, Int. J. Mass Spectrom., 2007, 267, 1-3, 54-62, https://doi.org/10.1016/j.ijms.2007.02.018 . [all data]

Locke and McIver, 1983 Locke, M.J.; McIver, R.T., Jr., Effect of Solvation on the Acid/Base Properties of Glycine, J. Am. Chem. Soc., 1983, 105, 4226. [all data]

Gapeev and Dunbar, 2003 Gapeev, A.; Dunbar, R.C., Na+ Affinities of Gas-Phase Amino Acids by Ligand Exchange Equilibrium, Int. J. Mass Spectrom., 2003, 228, 2-3, 825, https://doi.org/10.1016/S1387-3806(03)00242-2 . [all data]

Kish, Ohanessian, et al., 2003 Kish, M.M.; Ohanessian, G.; Wesdemiotis, C., The Na+ affinities of a-amino acids: side-chain substituent effects, Int. J. Mass Spectrom., 2003, 227, 3, 509, https://doi.org/10.1016/S1387-3806(03)00082-4 . [all data]

Abu-Eittah, et al., 1988 Abu-Eittah, R., et al., Bull. Chem. Soc. Japan., 1988, 61, 2609. [all data]

Notes

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

• Symbols used in this document:

  Cp,solid	Constant pressure heat capacity of solid
  S°solid,1 bar	Entropy of solid at standard conditions (1 bar)
  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
  ΔrG°	Free energy of reaction at standard conditions
  ΔrH°	Enthalpy of reaction 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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