Theoretical study on the poly(m-phenylene) derivatives with lower HOMO-LUMO gaps

- Three approaches are used to synthesize PMP derivatives.
- The HLGs of PMP derivatives are theoretically studied.
- PMP derivatives with quite small HLGs are obtained.

Poly(m-phenylene) (PMP) has received great attention for its rigid-rod backbone structure, high thermal stability, and promising electronic properties due to its broken conjugation. In this paper we report a theoretical study based on density functional theory calculations on the synthesis of PMP derivatives with lower HOMO-LUMO gaps (HLGs). Our calculations reveal an effective approach to obtain PMP derivatives with lower HLGs arising from decreased LUMO levels significantly via bridging the phenyl rings by C = X fragments (X = S, Se).

The LUMOs, HOMOs and HLGs of PMP, PMP-2X and PMP-2CX (X = O, S, Se).180