AB-INITIO GROUND-STATE CORRELATION CALCULATIONS FOR SEMICONDUCTORS WITH THE LOCAL ANSATZ

Ab initio correlation calculations for different semiconductors performed with the local ansatz are reported. The results include binding energies as well as equilibrium lattice distances and bulk moduli. Furthermore, we investigate how the results are influenced by the use of pseudopotentials. From the detailed correlation functions the strength of the effective local interactions within a bond-orbital model are determined. These vary strongly for the different materials. Comparisons to other correlation schemes are made, and shortcomings of some local-density-approximation results are explained. © 1995 The American Physical Society.