Electronic properties of the VO2(011) surface: density functional cluster calculations

This paper reviews electronic properties of the VO2(0 1 1) surface. In part icular it discusses the nature of surface V-O bonding. In addition, the ele ctronic states of the structurally different surface oxygen sites are descr ibed and correlated with their catalytic properties. The calculations are p erformed by means of the ab initio DFT method. The vanadium dioxide surface is modeled using clusters of different sizes. Results of the study confirm the bonding in vanadium dioxide as a mixture of ionic and covalent charact er. Further, nucleophilic properties of structurally non-equivalent surface oxygen sites are found to increase with their coordination number. It is s hown that in order to describe 5- and 6- fold vanadium centers correctly cl usters containing two physical layers are required as models. (C) 2001 Else vier Science B.V. All rights reserved.