TRANSPORT-PROPERTIES OF HE-CO MIXTURES

Classical trajectory calculations of diffusion, viscosity, thermal con ductivity and thermal diffusion in first-order kinetic theory have bee n performed using the MKWA ab initio potential energy surface of Moszy nski et al. [3] for temperatures in the range 77-800 K, and compared w ith available experimental data and previous calculations. For diffusi on and viscosity the results are consistent with experiment. The appro ximate to 5% disagreement between the present results and the measurem ents for thermal conductivity could stem in part from the omission of higher-order terms in the kinetic theory expansion. The results for th ermal diffusion suggest that the repulsive part of the potential energ y surface may be too anisotropic. While there are no measurements for DPR and viscomagnetic effect cross-sections, comparison of the present results with previous calculations by Gianturco et al. [10, 14] sugge sts that in the region sampled in room temperature collisions the anis otropy of the MKWA potential energy surface by Moszynski et al. [3] is significantly less than that of a surface reported earlier by Thomas ct al. [12].