Ladderization of polycyclic aromatic hydrocarbons enhances electrical conductivity through additional coherent channels

Abstract

Achieving high-conductance molecular devices on a large scale is a fundamental challenge. While extending π-conjugation is a facile approach, significant conductance enhancement remains difficult. We demonstrate that ladder-type polycyclic aromatic hydrocarbons synthesized via a Scholl reaction provide high conductance, as the ladder molecule 2TP exhibits a conductance (10^−3.74G₀) that is 1.36 orders of magnitude higher than that of its non-ladder analogue. Theoretical calculations attribute this enhancement not only to the reduced HOMO–LUMO gap but predominantly to the increased coherent electron transport channels. This work establishes ladderization as a powerful strategy for constructing high-conductance molecular devices.