First-principles local pseudopotentials for group-IV elements

Abstract

A simple scheme is proposed for generating first-principles local pseudopotentials, and applied to group-IV elements. The scheme is based on solving Kohn-Sham equations inversely, using the density from a nonlocal pseudopotential calculation. The generated local pseudopotentials have been applied in the calculations of dimers and solids including diamond and fcc structures of Si, Ge, and Sn. Fairly good results are obtained for bond lengths and lattice constants, while the results for energies and energy eigenvalues (e.g., excitation energies of atoms and band structures of solids) compare less well with those given by the corresponding nonlocal pseudopotentials. However, our work indicates the important features required by a good local pseudopotential of a group-IV element.