Electronic State of Hydroxyl-terminated Dimeric Titanium Structure

Abstract

A dimeric titanium planar structure conventionally explains surface reactions of TiO₂ photocatalysis. Although it has been assumed to be planar, we found that the hydroxyl-terminated cluster model (Ti₂O₆H₄) essentially has a non-planar structure calculated with B3LYP/6-311G. The hydrogen atom positions shift the HOMO and LUMO energy levels, relating to photocatalytic oxidation and reduction abilities. The results indicate that settling a new larger model to fit many phenomena quantitatively is highly required since the planar structure potentially involves a severe electronic problem.