Controlled Intramolecular Charge Transfer Using a Sulfur-Containing Acceptor Group

Abstract

A series of donor–acceptor (D–A) and donor–acceptor–donor (D–A–D) molecules containing anthracene chromophores paired with a sulfur-containing acceptor group have been prepared. The oxidation state of the acceptor sulfur atom controls the degree of charge transfer character in the excited state wave function. Steady-state photoluminescence spectroscopy shows more pronounced solvatochromism with increasing sulfur oxidation state. Computational methods (DFT/TD-DFT) are used to show that orbital mixing between donor and acceptor is facilitated as the oxidation state of the acceptor sulfur is increased.