Long range interaction energies using Gaussian basis sets and a one center method

A one center method, based on the work of Karplus and Kolker, is discussed and used to calculate the induction energy, through O( R −8 ), for the H(l s ) – H + interaction employing two types of Gaussian basis sets constructed from functions of the form { r j e −αr 2 }. The effective hydrogen atom excitation energies and transition multipole moment matrix elements generated in these calculations are used to calculate the dispersion energy for the H(l s ) – H(l s ) interaction, through O( R −10 ), and the R −9 triple dipole energy corresponding to the interaction of three H(l s ) atoms. The results indicate that Gaussian functions can form good basis sets for obtaining long range forces for a variety of multipole interaction energies.