Theoretical study of the formation process of HLCT state in multiple donor–acceptor molecular systems

Hybridized local and charge-transfer excited state (HLCT) is an excited state formed by the re-interaction of the intrinsic locally-excited (LE) state and charge-transfer (CT) state. In this paper, a donor–acceptor (D-A) molecule TPA-Nz is used as a benchmark to analyze the formation of the HLCT state. By changing the number of the D or A, the excited state energy and properties are summarized. We found that in a molecular with multiple donors or acceptors, the excited state formed can be divided into three types. If the energy of the intrinsic LE state is lower than the CT state, the HLCT state dominated by the LE state will be in the lowest energy, the HLCT state dominated by the CT state will be in the higher energy, and new CT state will be formed in the highest part. The number of new-formed excited state is equal to the number of acceptor.