EXP6 Fluids at Extreme Conditions Modeled by Two-Yukawa Potentials

0354873 - ÚCHP 2011 RIV US eng J - Journal Article
Krejčí, J. - Nezbeda, Ivo - Melnyk, R. - Trokhymchuk, A.
EXP6 Fluids at Extreme Conditions Modeled by Two-Yukawa Potentials.
Journal of Chemical Physics. Roč. 133, č. 9 (2010), 094503-1-8. ISSN 0021-9606. E-ISSN 1089-7690
R&D Projects: GA AV ČR IAA400720710
Institutional research plan: CEZ:AV0Z40720504
Keywords : fluids * thermodynamic properties * molecular dynamics method
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.920, year: 2010

A two-Yukawa representation of the EXP6 fluids at supercritical temperatures and high pressures has been developed and examined using molecular simulations. A uniquely defined mapping of the repulsive part of the EXP6 potential curve onto the two-Yukawa potential is used. Two ranges of temperatures, one encountered in geochemical applications Tgeo range and the other at conditions of detonations Tdet range, are considered and it is shown that the local structures of both fluids are practically identical. Deviations between the EXP6 and two-Yukawa potential functions at intermediate separations lead to differences in the thermodynamic properties of the two fluids at lower temperatures of the Tgeo range; at higher temperatures and in the high Tdet temperature range both the structural and thermodynamic properties of the EXP6 and two-Yukawa fluids are practically identical.
Permanent Link: http://hdl.handle.net/11104/0193779