Electronic Structure and Photoactivity of Organoarsenic Hybrid Polyoxometalates

Organofunctionalization of polyoxometalates (POMs) allows the preparation of hybrid molecular systems with tunable electronic properties. Currently, there are only a handful of approaches that allow for the fine-tuning of POM frontier molecular orbitals in a predictable manner. Herein, we demonstrate a new functionalization method for the Wells-Dawson polyoxotungstate [P2W18O62](6-) using arylarsonic acids which enables modulation of the redox and photochemical properties. Arylarsonic groups facilitate orbital mixing between the organic and inorganic moieties, and the nature of the organic substituents significantly impacts the redox potentials of the POM core. The photochemical response of the hybrid POMs correlates with their computed and experimentally estimated lowest unoccupied molecular orbital energies, and the arylarsonic hybrids are found to exhibit increased visible light photosensitivity comparable with that of arylphosphonic analogues. Arylarsonic hybridization offers a route to stable and tunable organic-inorganic hybrid systems for a range of redox and photochemical applications.

Automated summary

Organofunctionalization of polyoxometalates (POMs) allows for the preparation of hybrid molecular systems with tunable electronic properties. This study demonstrates a new functionalization method for Wells-Dawson polyoxotungstate [P2W18O62](6-) using arylarsonic acids, enabling modulation of the redox and photochemical properties. The arylarsonic hybrids show increased visible light photosensitivity and offer a route to stable and tunable organic-inorganic hybrid systems for various redox and photochemical applications.