Variational method for calculating molecular multipole polarizabilities using atom centered extended trial functions

An improvement of the variational method for calculating the electronic multipole polarizabilities is proposed. This modification allows the computation of the polarizabilities at any point and the results are compatible with the relations existing for a change of origin. It is applied to H₂, HF, CO and N₂ by using SCF wavefunctions developed on a limited basis. The computed polarizabilities are systematically too large but this discrepancy is attributed to the fact that the ground state is too far from the exact wavefunction.E.R.A. au C.N.R.S. No. 22.