title: Statistical thermodynamics of fluids with both dipole and quadrupole moments.
abstract: New Gibbs ensemble simulation data for a polar fluid modeled by a square-well potential plus dipole-dipole, dipole-quadrupole, and quadrupole-quadrupole interactions are presented. This simulation data is used in order to assess the applicability of the multipolar square-well perturbation theory [A. L. Benavides, Y. Guevara, and F. del Río, Physica A 202, 420 (1994)] to systems where more than one term in the multipole expansion is relevant. It is found that this theory is able to reproduce qualitatively well the vapor-liquid phase diagram for different multipolar moment strengths, corresponding to typical values of real molecules, except in the critical region. Hence, this theory is used to model the behavior of substances with multiple chemical bonds such as carbon monoxide and nitrous oxide and we found that with a suitable choice of the values of the intermolecular parameters, the vapor-liquid equilibrium of these species is adequately estimated.
authors.affiliation: Departamento Ingeniería Física, División de Ciencias e Ingenierías, Campus León, Universidad de Guanajuato, Apdo. E-413, León, Guanajuato 37150, México. alb@fisica.ugto.mx
authors.forename: Ana L
authors.initials: AL
authors.lastname: Benavides
authors.forename: Francisco J García
authors.initials: FJ
authors.lastname: Delgado
authors.forename: Francisco
authors.initials: F
authors.lastname: Gámez
authors.forename: Santiago
authors.initials: S
authors.lastname: Lago
authors.forename: Benito
authors.initials: B
authors.lastname: Garzón
mesh_terms: D002248:Carbon Monoxide / Q000737:chemistry*; D056004:Molecular Dynamics Simulation; D009609:Nitrous Oxide / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D002248:Carbon Monoxide; D009609:Nitrous Oxide