DENSITY-FUNCTIONAL STUDY OF STRUCTURAL AND ELECTRONIC-PROPERTIES OF CUBE-LIKE MGO CLUSTERS

The structural and electronic properties of neutral cube-like MgO clus ters comprising of 8, 18, 32, 48 and 64 atoms have been studied using density functional theory. Geometry optimization of all these stoichio metric clusters was done with C-2v symmetry. The binding energy and th e nearest-neighbor separation in these clusters show a progressive app roach towards their corresponding bulk values. The densities of states indicate an increase in the width of valence bands with increasing cl uster size. Total charge density plots show a relatively stronger depe ndence of magnesium charge density on the coordination number as compa red to that of oxygen in the 64-atom cluster.