Determination of potential energy surfaces for Ar–HCl and Kr–HCl from rotational linebroadening data

Using recent rotational linebroadening data at different temperatures of HCl–Ar and HCl–Kr mixtures, an attempt is made to determine anisotropic intermolecular potential surfaces for both systems. The parameters characterizing the anisotropic part of the potential were determined from numerical fitting of computed linebroadening cross sections using the model of Smith, Giraud, and Cooper. The potential for HCl–Ar obtained that way is found to be rather different from potential surfaces that have been put forward in the literature. A comparison between the different potentials is made. In the HCl–Kr case no other ’’experimental’’ potential surfaces are available for comparison.