Theoretical Study of the Surface Complex between TiO₂ and TCNQ Showing Interfacial Charge-Transfer Transitions

Abstract

The surface complex of TiO₂ nanoparticles and TCNQ was studied using density functional theory (DFT) calculations. The structure of the surface complex was optimized, showing an IR spectrum analogous to the experimental spectrum. From time-dependent DFT calculations based on this optimized structure, we demonstrated that the interfacial charge-transfer transitions from the HOMO of the surface-bound TCNQ molecule to the unoccupied levels of the TiO₂ nanocluster occur in the visible to near-IR region