Switchable NLO response induced by redox properties of Keggin-type polyoxometalate hybrids [PX11O39{Sn(p-C6H4I)}]4- (X = Mo, W)

Abstract

In this paper, the relationship between reversible redox properties and second-order nonlinear optical (NLO) responses for [PX11O39{Sn(p-C6H4I)}]4- (X = Mo, W) (named KMoSn[I] and KWSn[I]) has been systematically investigated by using density functional theory (DFT) method. It is noticeable that the NLO activity property of polyoxometalates (POMs) can be influenced by their oxidization process. Changing the central metal in the POM from Mo to W leads to a large increase in predicted hyperpolarizability and larger change in the energy of the charge transfer excitation when the POM is oxidized. The aim of this work is to combine the attractive redox properties and NLO response of polyoxometalates to obtain the switchable NLO materials.