Benzoic acid, 4-methoxy-

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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 as indicated in comments:
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
Δfgas-108.0 ± 0.33kcal/molCcbColomina, Jimenez, et al., 1978ALS
Quantity Value Units Method Reference Comment
gas98.7cal/mol*KN/AAlcolea P.M., 1994This value was calculated by semiempirical AM1 method for anti conformer. The same authors have calculated the value of S(298.15 K)=395 J/mol*K by ab initio 4-21G* basis set method. The value of 436 J/mol*K was estimated for equilibrium mixture of conformers by difference method [ Dorofeeva O.V., 1997].; GT

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
Δfsolid-134.2 ± 0.31kcal/molCcbColomina, Jimenez, et al., 1978ALS
Quantity Value Units Method Reference Comment
Δcsolid-891.42 ± 0.18kcal/molCcbColomina, Jimenez, et al., 1978Corresponding Δfsolid = -134.25 kcal/mol (simple calculation by NIST; no Washburn corrections); ALS

Constant pressure heat capacity of solid

Cp,solid (cal/mol*K) Temperature (K) Reference Comment
49.00323.Satoh and Sogabe, 1941T = 0 to 100 C. Mean value.; 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:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos
DRB - Donald R. Burgess, Jr.
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
Tfus456.15KN/AAnonymous, 1988Uncertainty assigned by TRC = 1. K; nominal value, from the catalog; TRC
Tfus456.75KN/AMarsh, 1987Uncertainty assigned by TRC = 0.2 K; recommended as fixed point for thermometry; TRC
Tfus457.8KN/AArmstrong, James, et al., 1979Uncertainty assigned by TRC = 0.5 K; TRC
Tfus457.KN/AHerbert, 1967Uncertainty assigned by TRC = 1. K; TRC
Quantity Value Units Method Reference Comment
Δvap22.kcal/molSub-FusPerlovich, Volkova, et al., 2008AC
Quantity Value Units Method Reference Comment
Δsub26.7 ± 0.1kcal/molGSPerlovich, Volkova, et al., 2008Based on data from 316. to 369. K.; AC
Δsub26.2 ± 0.1kcal/molMEStephenson and Malanowski, 1987See also Colomina, Jimenez, et al., 1978.; AC
Δsub26.24kcal/molN/AColomina, Jimenez, et al., 1978DRB

Enthalpy of sublimation

ΔsubH (kcal/mol) Temperature (K) Method Reference Comment
26.2 ± 0.1334.61VColomina, Jimenez, et al., 1978ALS

Enthalpy of fusion

ΔfusH (kcal/mol) Temperature (K) Method Reference Comment
6.7710456.70N/ASabbah and El Watik, 1992DH
7.15455.6DSCPerlovich, Volkova, et al., 2008AC
6.79457.8N/AAcree, 1991AC

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:


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:
B - John E. Bartmess
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi

Ionization energy determinations

IE (eV) Method Reference Comment
9.0 ± 0.2EIBenoit, 1973LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
C7H7O+12.8 ± 0.2COOHEIBenoit, 1973LLK
C8H7O2+12.5 ± 0.2OHEIBenoit, 1973LLK

De-protonation reactions

C8H7O3- + Hydrogen cation = Benzoic acid, 4-methoxy-

By formula: C8H7O3- + H+ = C8H8O3

Quantity Value Units Method Reference Comment
Δr340.8 ± 2.1kcal/molG+TSYamdagni, McMahon, et al., 1974gas phase; B
Quantity Value Units Method Reference Comment
Δr333.8 ± 2.0kcal/molIMREYamdagni, McMahon, et al., 1974gas phase; B

References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, Notes

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

Colomina, Jimenez, et al., 1978
Colomina, M.; Jimenez, P.; Roux, M.V.; Turrion, C., Thermochemical properties of benzoic acid derivatives VII. Enthalpies of combustion and formation of the o-, m-, and p-methoxy-benzoic acids, J. Chem. Thermodyn., 1978, 10, 661-665. [all data]

Alcolea P.M., 1994
Alcolea P.M., Spectroscopy of p-methoxybenzoic acid: an AM1 and ab initio study, Appl. Spectrosc., 1994, 48, 27-36. [all data]

Dorofeeva O.V., 1997
Dorofeeva O.V., Unpublished results. Thermocenter of Russian Academy of Science, Moscow, 1997. [all data]

Satoh and Sogabe, 1941
Satoh, S.; Sogabe, T., The heat capacities of some organic compounds containing nitrogen and the atomic heat of nitrogen. (3), Sci., Pap. Inst. Phys. Chem. Res. (Tokyo), 1941, 38, 238-245. [all data]

Anonymous, 1988
Anonymous, X., , NBS Spec. Publ. (U. S.) 260, 1988. [all data]

Marsh, 1987
Marsh, K.N., Recommended Reference Materials for the Realization of Physicochemical Properties, Blackwell Sci. Pub., Oxford, 1987. [all data]

Armstrong, James, et al., 1979
Armstrong, N.A.; James, K.C.; Wong, C.K., Inter-relationships between solubilities, distribution coefficients and melting points of some substituted benzoic and phenylacetic acids, J. Pharm. Pharmacol., 1979, 31, 1, 627, https://doi.org/10.1111/j.2042-7158.1979.tb13606.x . [all data]

Herbert, 1967
Herbert, A.J., Transition temperatures and transition energies of the p-n-alkoxy benzoic acids, from n-propyl to n-octadecyl, Trans. Faraday Soc., 1967, 63, 555, https://doi.org/10.1039/tf9676300555 . [all data]

Perlovich, Volkova, et al., 2008
Perlovich, German L.; Volkova, Tatyana V.; Manin, Alex N.; Bauer-Brandl, Annette, Extent and mechanism of solvation and partitioning of isomers of substituted benzoic acids: A thermodynamic study in the solid state and in solution, J. Pharm. Sci., 2008, 97, 9, 3883-3896, https://doi.org/10.1002/jps.21260 . [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]

Sabbah and El Watik, 1992
Sabbah, R.; El Watik, L., New reference materials for the calibration (temperature and energy) of differential thermal analysers and scanning calorimeters, J. Therm. Anal., 1992, 38(4), 855-863. [all data]

Acree, 1991
Acree, William E., Thermodynamic properties of organic compounds: enthalpy of fusion and melting point temperature compilation, Thermochimica Acta, 1991, 189, 1, 37-56, https://doi.org/10.1016/0040-6031(91)87098-H . [all data]

Benoit, 1973
Benoit, F., Substituent effects in mass spectrometry. III. Substituent effects in the dissociation of the molecular ions of para and meta subtituted benzoic acids, Org. Mass Spectrom., 1973, 7, 295. [all data]

Yamdagni, McMahon, et al., 1974
Yamdagni, R.; McMahon, T.B.; Kebarle, P., Substituent Effects on the Intrinsic Acidities of Benzoic Acids Determined by Gas Phase Proton Transfer Equilibria Measurements, J. Am. Chem. Soc., 1974, 96, 12, 4035, https://doi.org/10.1021/ja00819a063 . [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Phase change data, Gas phase ion energetics data, References