Exact‐exchange Hartree–Fock calculations for periodic systems. II. Results for graphite and hexagonal boron nitride

Abstract

AbstractThe ab‐initio LCAO‐HF method that was presented in a previous work is applied here to the study of graphite and hexagonal boron nitride monolayers. The dependence of total energy, band structure and density matrix on the computational parameters that control truncations in infinite sums over the translation vectors g of the direct lattice is first considered. For these systems it comes out that very good results can be obtained by neglecting all but the first few terms in the sums. For instance, for exchange contributions it is sufficient to consider integrals associated with the first 13 g vectors, suitably grouped, to obtain an error in total energy below 0.0001 a.u. The calculations were performed using an STO‐3G basis set; results concerning conformational minimum, bond energy, symmetric force constant, band structure, density of states, and population analysis are presented and discussed.