Tuning Symmetry‐Breaking Charge Transfer by Altering Connectivity Between Anthracene Chromophores

Abstract

In this study, we report on the dynamics of symmetry‐breaking charge transfer (SB‐CT) in a specific derivative of bianthracene, 9,9’,10,10’‐tetraphenyl‐2,2’‐bianthracene (TPBA). Unlike the conventional 9,9’‐bianthracene, TPBA exhibits a notably planar structure due to reduced steric hindrance between anthracene chromophores. This structural characteristic results in a pronounced short‐range charge transfer coupling, driven by substantial overlap integrals of hole and electron. This is in contrast to the 9,9’‐bianthracene case, where long‐range Coulombic coupling dominates while minimizing short‐range interactions. Consequently, TPBA reveals an adiabatic mixture between locally‐excited and charge‐transfer diabats, where the extent of their contributions is modulated by the dielectric properties of the surrounding environment. Furthermore, our investigation reveals that the SB‐CT reaction in TPBA is mainly influenced by solvation dynamics, akin to other molecules displaying SB‐CT. Additionally, the dynamics of triplet formation in TPBA vary depending on the solvent polarity. These findings underscore the significance of chromophore connectivity in efficiently manipulating excited‐state potential energy landscapes.