Electronic structure and reactivity of (TiO2)n (n = 1–10) nano-clusters: Global and local hardness based DFT study

Abstract

Electronic structure and reactivity of (TiO2)n (n=1–10) nano-clusters were investigated using density functional theory. The stability of clusters was discussed on the basis of binding energy per atom, second order energy difference and fragmentation energy. It was observed that (TiO2)3, (TiO2)5, (TiO2)7 and (TiO2)10 clusters were more stable compared to the neighboring clusters. The electron affinity, ionization energy, global hardness, Fukui functions and local hardness (ηk) for the most stable structures of (TiO2)n clusters were calculated in order to investigate reactivity of clusters as well as reactivity of each atom in the cluster. Our results revealed that atoms with ηk<0 (almost all of titanium atoms) were more favorable to react with a nucleophilic reagent while atoms with ηk>1 (almost all of oxygen atoms) were more favorable to react with an electrophilic reagent.