Virial coefficients of nitrogen from a quadrupolar site–site potential function

Abstract

This work describes a procedure for the numerical calculation of third virial coe±cients of simple linear molecules. The method is applied to nitrogen using a site-site model pair-potential and the triple dipole term. Values of volumetric and acoustic second and third virial coe±cients of nitrogen are reported over a wide range of temperature and compared with experimental data of several authors. The e®ect of including the quadrupole-quadrupole energy to the pair potential is investigated and the results suggest that the contributions of the quadrupole moment to second and third virial coe±cients are non-negligible at low temperatures.