STRUCTURAL AND THERMODYNAMIC PROPERTIES OF FLUID CARBON-DIOXIDE FROM A NEW AB-INITIO POTENTIAL-ENERGY SURFACE

Citation
G. Steinebrunner et al., STRUCTURAL AND THERMODYNAMIC PROPERTIES OF FLUID CARBON-DIOXIDE FROM A NEW AB-INITIO POTENTIAL-ENERGY SURFACE, The Journal of chemical physics, 109(8), 1998, pp. 3153-3160
Citations number
32
Categorie Soggetti
Physics, Atomic, Molecular & Chemical
ISSN journal
00219606
Volume
109
Issue
8
Year of publication
1998
Pages
3153 - 3160
Database
ISI
SICI code
0021-9606(1998)109:8<3153:SATPOF>2.0.ZU;2-D
Abstract
An intermolecular potential energy surface for the carbon dioxide dime r is calculated fully ab initio using a large basis set and including electron correlation. From this potential the dimer structure and the second virial coefficients are determined. In addition, it is applied in molecular dynamics simulations to obtain the fluid structure, the p ressure, the internal energy, the thermal pressure coefficient, and th e molar heat at constant volume. The results are compared with those f rom simulations with a previous ab initio potential. In this way we ga in information regarding the sensitivity of each property to the quali ty of the quantum chemically obtained potential. Equilibration of carb on dioxide simulations must be done with great care due to the very sl ow energy transfer between the intramolecular vibrations and the other degrees of freedom. This point is addressed in same detail. (C) 1998 American Institute of Physics. [S0021-9606(98)50532-6]