Periodic density functional study on V O bulk and 001/surface

Density functional calculations on periodic models are performed to investigate the structural and electronic properties of both V2O5 bulk and 001.surface. Full geometry optimizations of both V2O5 bulk and 001.surface are presented. For the bulk, the optimized structure is very close to the experimental one, the calculated band gap and binding energy are in very good agreement with experimental values, from population analysis it is observed that vanadyl oxygens are least ionic Oy0.37., doubly coordinated oxygens are ionic Oy0.56., while triply coordinated oxygens become the most ionic Oy0.68.. The structural and electronic properties of the surface are very close to those of the bulk. The interlayer interaction is mainly electrostatic and is found to be 4 kcalrmol. Surface acidic and basic properties are described in terms of projected density of states analysis. q1998 Elsevier Science B.V. All rights reserved