Molecular Cluster Approach to Magnesium and Calcium Oxide Crystals III. Charge Distribution Analysis of Some Hole Centres

The molecular cluster model is applied to the analysis of charge distribution and of symmetry of some hole centres (V⁻, V⁰, Li⁰, Na⁰), and also to impurity atoms of aluminium and to nitrogen ions in MgO. The calculations yield theoretical evidence of the models of hole centres derived from experimental data. Besides the essential effect of charge redistribution in the vicinity of impurity it is shown, e.g., the aluminium ion may be considered as triply charged only accounting for the charge of its nearest environment.