Toward a transferable parametrization for carbon in a periodic semi-empirical molecular orbital scheme

Abstract

A new parametrization for carbon is proposed within the framework of the complete neglect of differential overlap molecular orbital theory in a scheme for systems with periodic boundary conditions using large-unit-cells and Γ point sampling, with an accurate treatment of the long-range Coulomb tails of the interaction potentials. The new parametrization is obtained by fitting simultaneously experimental and theoretical data for electronic and structural properties of diamond and graphite. Remarkably, compared with other parametrizations existing in the literature and typically based on molecular data, it provides a better description of the relative stability between the two phases, but it is still unsatisfactory in the description of the elastic properties.