Molecular simulation of fluids with nonidentical intermolecular potentials: Thermodynamic properties of 105 + 126 Mie potential binary mixtures
Abstract
General methods for combining interactions between particles characterised by nonidentical intermolecular potentials are investigated. The combination methods are tested by performing molecular dynamics simulations to determine the pressure, energy, isochoric and isobaric heat capacities, thermal expansion coefficient, isothermal compressibility, JouleThomson coefficient, and speed of sound of 105 + 126 Mie potential binary mixtures. In addition to the two nonidentical Mie potentials, mixtures are also studied with nonidentical intermolecular parameters. The combination methods are compared with results obtained by simply averaging the Mie exponents. When either the energy or size parameters are nonidentical, very significant differences emerge in the thermodynamic properties predicted by the alternative combination methods. The isobaric heat capacity is the thermodynamic property that is most affected by the relative magnitude of the intermolecular potential parameters and the method for combining nonidentical potentials. Either the arithmetic or geometric combination of potentials provides a simple and effective way of performing simulations involving mixtures of components characterised by nonidentical intermolecular potentials, which is independent of their functional form.
 Authors:
 Technische Fakultät, FriedrichAlexanderUniversität ErlangenNürnberg, Martensstraße 5a, 91058 Erlangen (Germany)
 Centre for Molecular Simulation, Swinburne University of Technology, P.O. Box 218 Hawthorn, Victoria 3122 (Australia)
 Publication Date:
 OSTI Identifier:
 22416187
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 142; Journal Issue: 8; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; BINARY MIXTURES; COMPARATIVE EVALUATIONS; COMPRESSIBILITY; FLUIDS; INTERMOLECULAR FORCES; MOLECULAR DYNAMICS METHOD; PARTICLES; POTENTIALS; SOUND WAVES; SPECIFIC HEAT; THERMAL EXPANSION; VELOCITY
Citation Formats
Stiegler, Thomas, and Sadus, Richard J., Email: rsadus@swin.edu.au. Molecular simulation of fluids with nonidentical intermolecular potentials: Thermodynamic properties of 105 + 126 Mie potential binary mixtures. United States: N. p., 2015.
Web. doi:10.1063/1.4908530.
Stiegler, Thomas, & Sadus, Richard J., Email: rsadus@swin.edu.au. Molecular simulation of fluids with nonidentical intermolecular potentials: Thermodynamic properties of 105 + 126 Mie potential binary mixtures. United States. doi:10.1063/1.4908530.
Stiegler, Thomas, and Sadus, Richard J., Email: rsadus@swin.edu.au. 2015.
"Molecular simulation of fluids with nonidentical intermolecular potentials: Thermodynamic properties of 105 + 126 Mie potential binary mixtures". United States.
doi:10.1063/1.4908530.
@article{osti_22416187,
title = {Molecular simulation of fluids with nonidentical intermolecular potentials: Thermodynamic properties of 105 + 126 Mie potential binary mixtures},
author = {Stiegler, Thomas and Sadus, Richard J., Email: rsadus@swin.edu.au},
abstractNote = {General methods for combining interactions between particles characterised by nonidentical intermolecular potentials are investigated. The combination methods are tested by performing molecular dynamics simulations to determine the pressure, energy, isochoric and isobaric heat capacities, thermal expansion coefficient, isothermal compressibility, JouleThomson coefficient, and speed of sound of 105 + 126 Mie potential binary mixtures. In addition to the two nonidentical Mie potentials, mixtures are also studied with nonidentical intermolecular parameters. The combination methods are compared with results obtained by simply averaging the Mie exponents. When either the energy or size parameters are nonidentical, very significant differences emerge in the thermodynamic properties predicted by the alternative combination methods. The isobaric heat capacity is the thermodynamic property that is most affected by the relative magnitude of the intermolecular potential parameters and the method for combining nonidentical potentials. Either the arithmetic or geometric combination of potentials provides a simple and effective way of performing simulations involving mixtures of components characterised by nonidentical intermolecular potentials, which is independent of their functional form.},
doi = {10.1063/1.4908530},
journal = {Journal of Chemical Physics},
number = 8,
volume = 142,
place = {United States},
year = 2015,
month = 2
}

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