Non-muffin-tin version of the multiple scattering method for crystals and molecules

Abstract
We present a variational version of the multiple scattering method for non-muffin-tin potentials. Compared with a perturbational procedure where the non-muffin-tin parts of the potential are treated in the first order, the present method is both faster and more precise. In a trial numerical calculation for iron, we exhibit the virtues and main difficulties of the method.