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Leucine

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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
Deltacgas-853.26 ± 0.46kcal/molCcbWu, Zhu, et al., 1993 

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
Deltafliquid-155.10 ± 0.47kcal/molCcbWu, Zhu, et al., 1993ALS
Quantity Value Units Method Reference Comment
Deltafsolid-154.6kcal/molCcbHutchens, Cole, et al., 1963Heat of combustion is not reported; ALS
Deltafsolid-152.34 ± 0.22kcal/molCcbHuffman, Fox, et al., 1937Reanalyzed by Pedley, Naylor, et al., 1986, Original value = -153.49 kcal/mol; ALS
Quantity Value Units Method Reference Comment
Deltacsolid-853.72 ± 0.06kcal/molCcbTsuzuki and Hunt, 1957Reanalyzed by Cox and Pilcher, 1970, Original value = -853.08 ± 0.06 kcal/mol; ALS
Deltacsolid-856.01 ± 0.20kcal/molCcbHuffman, Fox, et al., 1937Reanalyzed by Pedley, Naylor, et al., 1986, Original value = -855.98 ± 0.20 kcal/mol; ALS
Deltacsolid-859.5kcal/molCcbFischer and Wrede, 1904Heat of combustion corrected for pressure; ALS
Deltacsolid-860.52kcal/molCcbLemoult, 1904ALS
Quantity Value Units Method Reference Comment
solid,1 bar50.619cal/mol*KN/AHutchens, Cole, et al., 1963DH

Constant pressure heat capacity of solid

Cp,solid (cal/mol*K) Temperature (K) Reference Comment
45.7298.Badelin, Kulikov, et al., 1990T = 298, 313, 333, 348 K.; DH
45.55298.Kulikov, Kozlov, et al., 1989T = 298 to 348 K.; DH
48.14298.15Spink and Wads, 1975DH
48.031298.15Hutchens, Cole, et al., 1963T = 11 to 310 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:
AC - William E. Acree, Jr., James S. Chickos
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
DH - Eugene S. Domalski and Elizabeth D. Hearing

Enthalpy of sublimation

DeltasubH (kcal/mol) Temperature (K) Method Reference Comment
35.5 ± 1.6401. - 517.TGALähde, Raula, et al., 2009AC
36.0 ± 0.2455.VSvec and Clyde, 1965ALS
36.0 ± 0.2455.MESvec and Clyde, 1965, 2Based on data from 446. - 464. K. See also Cox and Pilcher, 1970, 2 and Clyde and Svec, 1964.; AC

Enthalpy of phase transition

DeltaHtrs (kcal/mol) Temperature (K) Initial Phase Final Phase Reference Comment
0.0478352.crystaline, IIcrystaline, IGrunenberg, Bougeard, et al., 1984DH

Entropy of phase transition

DeltaStrs (cal/mol*K) Temperature (K) Initial Phase Final Phase Reference Comment
0.14352.crystaline, IIcrystaline, IGrunenberg, Bougeard, et al., 1984DH

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 by: John E. Bartmess

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

C6H12NO2- + Hydrogen cation = Leucine

By formula: C6H12NO2- + H+ = C6H13NO2

Quantity Value Units Method Reference Comment
Deltar339.1 ± 2.4kcal/molCIDCJones, Bernier, et al., 2007gas phase
Deltar339.0 ± 3.1kcal/molG+TSO'Hair, Bowie, et al., 1992gas phase
Quantity Value Units Method Reference Comment
Deltar332.2 ± 3.0kcal/molCIDCO'Hair, Bowie, et al., 1992gas phase

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:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Quantity Value Units Method Reference Comment
Proton affinity (review)218.6kcal/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity210.5kcal/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
8.51PEKlasinc, 1976LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C5H12N+9.9 ± 0.2?EIJunk and Svec, 1963RDSH

De-protonation reactions

C6H12NO2- + Hydrogen cation = Leucine

By formula: C6H12NO2- + H+ = C6H13NO2

Quantity Value Units Method Reference Comment
Deltar339.1 ± 2.4kcal/molCIDCJones, Bernier, et al., 2007gas phase; B
Deltar339.0 ± 3.1kcal/molG+TSO'Hair, Bowie, et al., 1992gas phase; B
Quantity Value Units Method Reference Comment
Deltar332.2 ± 3.0kcal/molCIDCO'Hair, Bowie, et al., 1992gas phase; B

IR 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: Coblentz Society, Inc.

Condensed Phase Spectrum

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IR spectrum
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Notice: Except where noted, spectra from this collection were measured on dispersive instruments, often in carefully selected solvents, and hence may differ in detail from measurements on FTIR instruments or in other chemical environments. More information on the manner in which spectra in this collection were collected can be found here.

Notice: Concentration information is not available for this spectrum and, therefore, molar absorptivity values cannot be derived.

Additional Data

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Owner COBLENTZ SOC.
Collection (C) 2018 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin SMITH KLINE & FRENCH LABS.
Source reference COBLENTZ NO. 05815
Date 1965/06/18
Name(s) leucine
State SOLID (MULL, KBr DISC)
INACTIVE KBr PLATES AROUND 300-200 CM-1
SPECTRAL CONTAMINATION DUE TO OIL AROUND 2900 CM-1
Instrument PERKIN-ELMER 521 (GRATING)
Instrument parameters ORDER CHANGES: 1999, 690 CM-1
Resolution 2
Sampling procedure TRANSMISSION
Data processing DIGITIZED BY COBLENTZ SOCIETY (BATCH I) FROM HARD COPY
Melting point 294 C, DECOMP.

This IR spectrum is from the Coblentz Society's evaluated infrared reference spectra collection.


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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Mass 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- 347
NIST MS number 228159

All mass spectra in this site (plus many more) are available from the NIST/EPA/NIH Mass Spectral Library. Please see the following for information about the library and its accompanying search program.


References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), NIST Free Links, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Wu, Zhu, et al., 1993
Wu, D.; Zhu, Y.; Gao, Z.; Qu, S., Determination of combustion heat of some amino acids, Wuhan Daxue Xuebao Ziran Kexueban, 1993, 78-82. [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]

Huffman, Fox, et al., 1937
Huffman, H.M.; Fox, S.W.; Ellis, E.L., Thermal data. VII. The heats of combustion of seven amino acids, J. Am. Chem. Soc., 1937, 59, 2144-21. [all data]

Pedley, Naylor, et al., 1986
Pedley, J.B.; Naylor, R.D.; Kirby, S.P., Thermochemical Data of Organic Compounds, Chapman and Hall, New York, 1986, 1-792. [all data]

Tsuzuki and Hunt, 1957
Tsuzuki, T.; Hunt, H., Heats of combustion. VI. The heats of combustion of some amino acids, J. Phys. Chem., 1957, 61, 1668. [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]

Fischer and Wrede, 1904
Fischer, E.; Wrede, F., Uber die Verbrennungswarme einiger organischer Verbindungen, Sitzungsber. Dtsch. Akad. Wiss. Berlin Kl. Math. Phys. Tech., 1904, 687-715. [all data]

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

Spink and Wads, 1975
Spink, C.H.; Wads, I., Thermochemistry of solutions of biochemical model compounds. 4. The partial molar heat capacities of some amino acids in aqueous solution, J. Chem. Thermodynam., 1975, 7, 561-572. [all data]

Lähde, Raula, et al., 2009
Lähde, Anna; Raula, Janne; Malm, Jari; Kauppinen, Esko I.; Karppinen, Maarit, Sublimation and vapour pressure estimation of l-leucine using thermogravimetric analysis, Thermochimica Acta, 2009, 482, 1-2, 17-20, https://doi.org/10.1016/j.tca.2008.10.009 . [all data]

Svec and Clyde, 1965
Svec, H.J.; Clyde, D.D., Vapor pressures of some «alpha»-amino acids, J. Chem. Eng. Data, 1965, 10, 151. [all data]

Svec and Clyde, 1965, 2
Svec, H.J.; Clyde, D.D., Vapor Pressures of Some «alpha»-Amino Acids., J. Chem. Eng. Data, 1965, 10, 2, 151-152, https://doi.org/10.1021/je60025a024 . [all data]

Cox and Pilcher, 1970, 2
Cox, J.D.; Pilcher, G., Thermochemistry of Organic and Organometallic Compounds, Academic Press Inc., London, 1970, 643. [all data]

Clyde and Svec, 1964
Clyde, D.D.; Svec, H., , U. S. Atomic Energy Comm. IS-790, 1964, 1. [all data]

Grunenberg, Bougeard, et al., 1984
Grunenberg, A.; Bougeard, D.; Schrader, B., DSC-investigations of 22 crystalline neutral aliphatic amino acids in the temperature range 233 to 423 K, Thermochim. Acta, 1984, 77, 59-66. [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]

O'Hair, Bowie, et al., 1992
O'Hair, R.J.; Bowie, J.H.; Gronert, S., Gas Phase Acidity of the alpha-Amino Acids, Int. J. Mass Spectrom. Ion Proc., 1992, 117, 23, https://doi.org/10.1016/0168-1176(92)80083-D . [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]

Klasinc, 1976
Klasinc, L., Application of photoelectron spectroscopy to biologically active molecules and their constituent parts, J. Electron Spectrosc. Relat. Phenom., 1976, 8, 161. [all data]

Junk and Svec, 1963
Junk, G.; Svec, H., The mass spectra of the «alpha»-amino acids, J. Am. Chem. Soc., 1963, 85, 839. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), NIST Free Links, References