using the gaussian 2003 software and mp2 /6 – 311+ g method for the c2h4 : o2, co:cl2 andco2:co2 pairs and mp2/6-311++g** method for the co2:h2o pair and b3lyp/6-31g methodfor the o2:o2 pair the optimized interaction energies between two considered pair molecules ofstudied gases(c2h4:o2, co:cl2, co2:h2o, o2:o2 and co2:co2 pairs) as a function of thedistances between the centers of two considere...

The second virial coefficients are given as a spherical-core contribution plus a series of nonspherical perturbation terms. A revised analysis is given of the effect of long-range nonspherical terms in the intermolecular potential on the second virial coefficient given by a preferred HFDIDl spherical core treatment of the integration for small intermolecular distances. This effect is consid...

a revised analysis of the effect of long-range nonspherical terms in the intermolecular potential on the second virial coefficient is presented with a preferred hartree-fock-dispersion functional (hfd-c) spherical core treatment of the integrations for small intermolecular distances. a set of modified numerical tables for the accurate calculation of the nonspherical contribution to the second v...