A FULL-POTENTIAL LINEAR-MUFFIN-TIN-ORBITAL STUDY OF WATER-ADSORPTION ON AND SATURATION IN SMALL SI CLUSTERS

The structure and geometrical parameters for water adsorption on a sma ll-silicon-cluster surface have been studied using the linear-muffin-t in-orbital method. We find that the most favoured adsorption site is t he atop site of the capped atom for Si-5, Si-6, and Si-7 clusters. Whe n H2O adsorbs at such sites, the silicon clusters are elongated in the direction of the axis connecting one capped atom to another capped at om. Also, saturation studies have been performed. Each of these cluste rs can only adsorb two H2O molecules at two atop sites of capped atoms . These clusters cannot adsorb any more H2O molecules.