Calculation of multipole polarizability and dispersion coefficients for Helium by WBEPM and variationally stable procedure

Based on the weakest bound electron potential model (WBEPM) theory, method of calculating the multipole dynamic polarizability and dispersion coefficients for Helium by a variationally stable procedure is established. The matrix elements and a group of linear equations, involving in this approach, are derived analytically. As an application, the polarizability and two-body dispersion coefficients between Helium atoms in their ground states are calculated concretely and are compared with those calculated previously by other procedures. It is found that the calculated results are consistent with those of others. (authors)