Low-energy scattering of excited helium atoms by rare gases. I. The model potentials

The construction of semi-empirical model potentials for systems composed of helium in an excited state (He*) and a rare-gas atom (He or Ne) is described. The model of the atom-atom pair which has been adopted is one in which the excited electron is included explicitly, but the residual He + ion and the rare-gas atom are treated simply as cores which may be polarised. The results obtained are in satisfactory agreement with other calculations where they are available.