Z-Shaped Pentaleno-Acene Dimers with High Stability and Small Band Gap

Abstract

Acene-based materials have promising applications for organic electronics but the major constrain comes from their poor stability. Herein a new strategy to stabilize reactive acenes, by fusion of an anti-aromatic pentalene unit onto the zigzag edges of two acene units to form a Z-shaped acene dimer, is introduced. The Z-shaped acene dimers are extremely stable and show a small energy gap resulting from intramolecular donor-acceptor interactions. X-ray crystallographic analysis revealed their unique geometry and one-dimensional slip-stack columnar structure. Besides optical and electrochemical characterizations, solution-processed field-effect transistors were also fabricated.

Keywords: acenes; dimerization; materials science; polycycles; structure elucidation.