Thermodynamic properties of 1-phenylnaphthalene and 2-phenylnaphthalene

Published

January 18, 2014

Author(s)

Robert D. Chirico, Andrei F. Kazakov, William V. Steele

Abstract

Measurements leading to the calculation of thermodynamic properties in the ideal-gas state for 1- phenylnaphthalene (Chemical Abstracts registry number [605-02-7]) and 2-phenylnaphthalene (Chemical Abstracts registry number [612-94-2]) are reported. Experimental methods for 1-phenylnaphthalene were adiabatic heat-capacity calorimetry, differential scanning calorimetry, inclined-piston manometry, comparative ebulliometry, vibrating-tube densitometry, and combustion calorimetry. For 2- phenylnaphthalene, the experimental methods were adiabatic heat-capacity calorimetry, differential scanning calorimetry, comparative ebulliometry, and combustion calorimetry. Critical properties were estimated for both compounds. Molar thermodynamic functions (enthalpies, entropies, and Gibbs energies) for the condensed and ideal-gas states were derived from the experimental studies at selected temperatures. Statistical calculations were performed based on molecular geometry optimization and vibrational frequencies calculated at the B3LYP/6-31+G(d,p) and B3LYP/cc-pVTZ levels of theory. Ideal-gas entropies derived with the independent methods are shown to be in good accord for 1-phenylnaphthalene, but significant differences are apparent for 2-phenylnaphthalene. These differences are likely due to a disorder of unknown type in the crystals of 2- phenylnaphthalene at low temperatures, as evidenced by the presence of a glass-like transition in the measured heat capacities for the solid state. All experimental results are compared with property values reported in the literature.

Citation

Journal of Chemical Thermodynamics

Volume

73

Pub Type

Journals

Download Paper

https://doi.org/10.1016/j.jct.2014.01.006

Keywords

ideal-gas entropy, heat capacity, vapor pressure, enthalpy of combustion, computational chemistry

Citation

Chirico, R. , Kazakov, A. and Steele, W. (2014), Thermodynamic properties of 1-phenylnaphthalene and 2-phenylnaphthalene, Journal of Chemical Thermodynamics, [online], https://doi.org/10.1016/j.jct.2014.01.006 (Accessed April 25, 2024)