No abstract

No abstract

No abstract

The periodic ab initio Hartree-Fock approach is applied to the Li, Na, K, Be, Mg, Ca and Mn oxides, and to Al 2 O 3 (corundum) and SiO 2 (a-quartz). A local basis set (‘atomic orbitals’) is used. The equilibrium geometry, the formation energy and the bulk modulus are calculated, with reasonable agreement with experiment. The influence of the environment on the oxygen ions is discussed through the Mulliken population and band structure data.

An ab initio periodic Hartreee-Fock study of sillco-chabalik is presented. Complete geometq optimization has been performed using both a minimal STO-3G and an extended (split-valence plus polarization functions) basis set; the results are similar to those obtained with a semi-classical approach based on a model potential. The more sophisticated basis set has been adopted for characterizing the gmund-state wave-function. The electrostatic potential within the main cavity is calculated and analyzed.