Data at NIST subscription sites:

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, References, Notes

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:
DRB - Donald R. Burgess, Jr.
ALS - Hussein Y. Afeefy, Joel F. Liebman, and Stephen E. Stein
GT - Glushko Thermocenter, Russian Academy of Sciences, Moscow

Quantity Value Units Method Reference Comment
Δfgas50.1 ± 1.1kJ/molReviewRoux, Temprado, et al., 2008There are sufficient high-quality literature values to make a good evaluation with a high degree of confidence. In general, the evaluated uncertainty limits are on the order of (0.5 to 2.5) kJ/mol.; DRB
Δfgas50.00 ± 0.63kJ/molCcbProsen, Gilmont, et al., 1945Hf by Prosen, Johnson, et al., 1946; ALS
Δfgas48.0kJ/molN/ASchmidlin, 1906Value computed using ΔfHliquid° value of 10.0 kj/mol from Schmidlin, 1906 and ΔvapH° value of 38.0 kj/mol from Prosen, Gilmont, et al., 1945.; DRB

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
69.85200.Draeger, 1985Recommended values agree better with experimental heat capacities than results of calculation [ Chao J., 1984]. All other statistically calculated values [ Pitzer K.S., 1943, Taylor W.J., 1946, Scott D.W., 1962] are in close agreement with selected ones, except for high temperatures.; GT
103.7 ± 0.4298.15

Constant pressure heat capacity of gas

Cp,gas (J/mol*K) Temperature (K) Reference Comment
130.08 ± 0.26371.20Scott D.W., 1962Please also see Montgomery J.B., 1942, Pitzer K.S., 1943, Taylor W.J., 1946.; GT
137.2 ± 1.3393.
138.87 ± 0.27396.20
149.16 ± 0.30427.20
149.4 ± 1.7428.
160.33 ± 0.32462.20
159.0 ± 1.7463.
171.46 ± 0.34500.20


Go To: Top, Gas phase thermochemistry data, Notes

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

Roux, Temprado, et al., 2008
Roux, M.V.; Temprado, M.; Chickos, J.S.; Nagano, Y., Critically Evaluated Thermochemical Properties of Polycyclic Aromatic Hydrocarbons, J. Phys. Chem. Ref. Data, 2008, 37, 4, 1855-1996. [all data]

Prosen, Gilmont, et al., 1945
Prosen, E.J.; Gilmont, R.; Rossini, F.D., Heats of combustion of benzene, toluene, ethyl-benzene, o-xylene, m-xylene, p-xylene, n-propylbenzene, and styrene, J. Res. NBS, 1945, 34, 65-70. [all data]

Prosen, Johnson, et al., 1946
Prosen, E.J.; Johnson, W.H.; Rossini, F.D., Heats of combustion and formation at 25°C of the alkylbenzenes through C10H14, and of the higher normal monoalkylbenzenes, J. Res. NBS, 1946, 36, 455-461. [all data]

Schmidlin, 1906
Schmidlin, M.J., Recherches chimiques et thermochimiques sur la constitution des rosanilines, Ann. Chim. Phys., 1906, 1, 195-256. [all data]

Draeger, 1985
Draeger, J.A., The methylbenzenes II. Fundamental vibrational shifts, statistical thermodynamic functions, and properties of formation, J. Chem. Thermodyn., 1985, 17, 263-275. [all data]

Chao J., 1984
Chao J., Chemical thermodynamic properties of toluene, o-, m- and p-xylenes, Thermochim. Acta, 1984, 72, 323-334. [all data]

Pitzer K.S., 1943
Pitzer K.S., The thermodynamics and molecular structure of benzene and its methyl derivatives, J. Am. Chem. Soc., 1943, 65, 803-829. [all data]

Taylor W.J., 1946
Taylor W.J., Heats, equilibrium constants, and free energies of formation of the alkylbenzenes, J. Res. Nat. Bur. Stand., 1946, 37, 95-122. [all data]

Scott D.W., 1962
Scott D.W., Toluene: thermodynamic properties, molecular vibrations, and internal rotation, J. Phys. Chem., 1962, 66, 911-914. [all data]

Montgomery J.B., 1942
Montgomery J.B., The heat capacity of organic vapors. IV. Benzene, fluorobenzene, toluene, cyclohexane, methylcyclohexane and cyclohexene, J. Am. Chem. Soc., 1942, 64, 2375-2377. [all data]


Go To: Top, Gas phase thermochemistry data, References