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Azobenzene

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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
Deltafsolid374.kJ/molCcbLemoult, 1908 
Quantity Value Units Method Reference Comment
Deltacsolid-6452.kJ/molCcbWieland, Heymann, et al., 1934 
Deltacsolid-6468.1 ± 3.8kJ/molCcbSwietoslawski and Bobinska, 1929 
Deltacsolid-6525.8kJ/molCcbLemoult, 1908 

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:
BS - Robert L. Brown and Stephen E. Stein
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny, director
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
Tboil566.2KN/AAldrich Chemical Company Inc., 1990BS
Quantity Value Units Method Reference Comment
Tfus341.KN/ABergmann, Fischer, et al., 1953Uncertainty assigned by TRC = 3. K; TRC
Tfus340.KN/ASorum and Durand, 1952Uncertainty assigned by TRC = 1. K; TRC
Quantity Value Units Method Reference Comment
Deltasub93.84 ± 0.12kJ/molVCammenga, Behrens, et al., 1977Hfusion=22.7 kJ/mol; 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
376.7 - 566.5.091772671.499-41.23Stull, 1947Coefficents calculated by NIST from author's data.

Enthalpy of fusion

DeltafusH (kJ/mol) Temperature (K) Reference Comment
22.368340.5Cingolani and Berchiesi, 1974DH
22.389342.2Eykman, 1889DH

Entropy of fusion

DeltafusS (J/mol*K) Temperature (K) Reference Comment
65.59340.5Cingolani and Berchiesi, 1974DH
65.4342.2Eykman, 1889DH

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:


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: Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein

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

C12H10N2 = Azobenzene

By formula: C12H10N2 = C12H10N2

Quantity Value Units Method Reference Comment
Deltar-48.0 ± 1.5kJ/molCmCammenga, Behrens, et al., 1977solid 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 compiled as indicated in comments:
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

IE (eV) Method Reference Comment
8.5 ± 0.05EINatalis and Franklin, 1981LLK
8.4PEPetrachenko, Vovna, et al., 1993Vertical value; LL
8.4PEFurin, Petrachenko, et al., 1989Vertical value; LL
8.5PERao, 1975Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C6H5+11.9 ± 0.1C6H5+N2EINatalis and Franklin, 1981LLK
C6H5N2+9.8 ± 0.1C6H5EINatalis and Franklin, 1981LLK
C12H8+14.7 ± 0.05N2+2HEINatalis and Franklin, 1981LLK
C12H9+12.4 ± 0.1N2+HEINatalis and Franklin, 1981LLK
C12H10+11.6 ± 0.2N2EINatalis and Franklin, 1981LLK

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

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


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 NIST Mass Spectrometry Data Center, 1990.
NIST MS number 113361

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.


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, Eugeny B. Stern, Antonina A. Goncharova, Natalia A. Messineva, Natalia V. Trusova, Margarita V. Efimkina

Spectrum

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UVVis spectrum
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Additional Data

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Source den Hertog, Henkens, et al., 1952
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. 610
Instrument n.i.g.

Gas Chromatography

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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

Kovats' RI, non-polar column, isothermal

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Column type Active phase Temperature (C) I Reference Comment
PackedOV-101150.1591.Delley and Friedrich, 1977Gas Chrom Q (80-100 mesh)

Kovats' RI, non-polar column, custom temperature program

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Column type Active phase I Reference Comment
PackedSE-301556.Ramsey, Lee, et al., 1980He, Chromosorb G HP (80-100 mesh); Column length: 1.5 m; Program: not specified

Normal alkane RI, non-polar column, custom temperature program

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Column type Active phase I Reference Comment
CapillaryMethyl Silicone1566.Zenkevich, 1994Program: not specified
OtherMethyl Silicone1556.Ardrey and Moffat, 1981Program: not specified

References

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

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

Lemoult, 1908
Lemoult, M.P., Recherches theoriques et experimentales sur les chaleurs de combustion et de formation des composes organiques, Ann. Chim. Phys., 1908, 14, 289-310. [all data]

Wieland, Heymann, et al., 1934
Wieland, H.; Heymann, K.; Tsatsas, T.; Juchum, D.; Varvoglis, G.; Labriola, G.; Dobbelstein, O.; Boyd-Barrett, H.S., Uber das Auftreten freier Radikale bei chemischen Reaktionen. VIII, Ann., 1934, 514, 145-181. [all data]

Swietoslawski and Bobinska, 1929
Swietoslawski, M.W.; Bobinska, M.J., O cieple spalania kamfory, azobenzenu i hydrazobenzenu - Sur la chaleur de combustion du comphre, de l'hydrazobenzene, Rocz. Chem., 1929, 9, 723-730. [all data]

Aldrich Chemical Company Inc., 1990
Aldrich Chemical Company Inc., Catalog Handbook of Fine Chemicals, Aldrich Chemical Company, Inc., Milwaukee WI, 1990, 1. [all data]

Bergmann, Fischer, et al., 1953
Bergmann, E.D.; Fischer, E.; Jaffe, J.H., Exalted Distortion Polarizations of Some COlored Hydrocarbons, J. Am. Chem. Soc., 1953, 75, 3230-3. [all data]

Sorum and Durand, 1952
Sorum, C.H.; Durand, E.A., The Melting of Binary Eutectics, J. Am. Chem. Soc., 1952, 74, 1071. [all data]

Cammenga, Behrens, et al., 1977
Cammenga, H.K.; Behrens, E.; Wolf, F., Thermal isomerization of cis-azobenzene in the solid state in React. Solids, [Proc. Int. Symp.],, ed. J. Wood, O. Lindqvist, C. Helgesson, Plenum: New York,NY, 1977, 481-486. [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]

Cingolani and Berchiesi, 1974
Cingolani, A.; Berchiesi, G., Thermodynamic properties of organic compounds. 1. A DSC study of phase transitions in aliphatic dicarboxylic acids, J. Therm. Anal., 1974, 6, 87-90. [all data]

Eykman, 1889
Eykman, J.F., Zur kryoskopischen Molekulargewichtsbestimmung, Z. Physik. Chem., 1889, 4, 497-519. [all data]

Natalis and Franklin, 1981
Natalis, P.; Franklin, J.L., Ionization and dissociation of diphenyl and condensed-ring aromatics by electron impact. III. Azobenzene, Int. J. Mass Spectrom. Ion Phys., 1981, 40, 35. [all data]

Petrachenko, Vovna, et al., 1993
Petrachenko, N.E.; Vovna, V.I.; Furin, G.G., Photoelectron HeI spectra of fluorinated azo- and azoxy-benzenes, J. Fluorine Chem., 1993, 63, 85. [all data]

Furin, Petrachenko, et al., 1989
Furin, G.G.; Petrachenko, N.E.; Vovna, V.I., Photoelectron spectra of fluorine-containing azoxybenzenes, J. Org. Chem. USSR, 1989, 26, 1725, In original 1998. [all data]

Rao, 1975
Rao, C.N.R., Lone-pair ionization bands of chromophores in the photoelectron spectra of organic molecules, Indian J. Chem., 1975, 13, 950. [all data]

den Hertog, Henkens, et al., 1952
den Hertog, H.J.; Henkens, C.H.; van Roon, J.H., Reactivity of 4-nitropyridine-n-oxide (III) Reduction in alkaline medium, Recl. Trav. Chim. Pays-Bas, 1952, 71, 1145-1151. [all data]

Delley and Friedrich, 1977
Delley, R.; Friedrich, K., System CG 72 von bevorzugten Trennflüssigkeiten für die Gas-Chromatographie, Chromatographia, 1977, 10, 10, 593-600, https://doi.org/10.1007/BF02265037 . [all data]

Ramsey, Lee, et al., 1980
Ramsey, J.D.; Lee, T.D.; Osselton, M.D.; Moffat, A.C., Gas-liquid chromatographic retention indices of 296 non-drug substances on SE-30 or OV-1 likely to be encountered in toxicological analyses, J. Chromatogr., 1980, 184, 2, 185-206, https://doi.org/10.1016/S0021-9673(00)85641-1 . [all data]

Zenkevich, 1994
Zenkevich, I.G., Contemporary State of Informational Maintenance for Gas Chromatographic Identification of Chlorinated Polycyclic Aromatic Compounds, Zh. Ecol. Khim., 1994, 3, 2, 111-119. [all data]

Ardrey and Moffat, 1981
Ardrey, R.E.; Moffat, A.C., Gas-liquid chromatographic retention indices of 1318 substances of toxicological interest on SE-30 or OV-1 stationary phase, J. Chromatogr., 1981, 220, 3, 195-252, https://doi.org/10.1016/S0021-9673(00)81925-1 . [all data]


Notes

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