<i>Ab-initio</i> study of free standing TiO2 clusters: Stability and magnetism

Abstract

We report the structural behavior of nanoscale Titanium Dioxide (TiO2) clusters as well as their magnetic properties by varying the cluster size with the help of ground state geometries. The clusters of atomic scale rutile (TiO2)n, where n = 1-11, have been considered and geometrically stabilized through the Density Functional Theory as implemented in Vienna ab-initio Simulation Package. It is being observed that as the size of cluster increases from n = 2 to 11, the total energy decreases. The results of formation energy reveal the fact that as the cluster grows, it moves towards the stability and it is observed that n = 11 is the most stable structure. The stabilized clusters are different in geometries and co-ordination numbers. Finally, all the clusters have been investigated with self consistent treatment of spin orbit coupling for magnetism studies. The magnetic properties of free clusters depict oscillatory behavior for magnetic moment with respect to the cluster size.