VARIATIONAL APPROACH TO CONTINUUM ORBITALS IN A SPLINE BASIS - AN APPLICATION TO H-2+ PHOTOIONIZATION

A variational approach for the determination of continuum orbitals, recently proposed in the one-dimensional case, is generalized to the multicenter molecular problem. A test application is performed on the H-2+ molecule in the one-center approximation, with a radial basis of B-spline functions. The resulting eigenvalue equation is solved by inverse subspace iteration giving a full set of K-matrix normalized solutions at each prefixed energy. Excellent numerical stability allows expansion up to l = 20, giving very satisfactory agreement with exact results. The potential of a multicenter LCAO-type implementation is pointed out.