The properties of defective SnO2 crystalline grains were evaluated quantum-mechanically by using a tight-binding total-energy formulation with a rigid-lattice model. The shape of the grains was constructed on the basis of known features of the nanocrystalline material and the grain size was comparable with those observed in experiments. The grains had a rutile lattice and the presence of vacancies in one or other of the two sub-lattices was accounted for. The calculations indicated that, owing to the peculiar connectivity of the grains, the effect of a vacancy was critical and alters the stability of bonding even when the defect concentration was minimal.

A Simple Tight-Binding Model of Vacancies in SnO2 Crystalline Grains. A.M.Mazzone: Philosophical Magazine Letters, 2004, 84[4], 275-82