Molecular Design Strategy for Simultaneously Strong Luminescence and High Mobility: Multichannel CH-π Interaction

It is a big challenge to achieve high-performance organic semiconductor materials integrating both high luminescence efficiency and carrier mobility, because they are commonly regarded as a pair of contradiction. Here, combining a tight-binding model and density functional theory/time-dependent density functional theory, we propose a theoretical protocol to characterize the luminescence efficiency via an excitonic effective mass and charge transport ability via charge effective mass at the same level. Applying this protocol to a series of organic semiconductor materials, we find that the multichannel CH-pi interaction can induce a heavy excitonic effective mass and light charge effective mass, which effectively balance the light-emitting efficiency and carrier mobility. Thus, a practical molecular design strate figured out to exploit novel organic semiconductor materials with strong luminescence and fast carrier transport simultaneously.

Automated summary

A theoretical protocol combining a tight-binding model and density functional theory was proposed to characterize luminescence efficiency and charge transport ability simultaneously. It was found that multichannel CH-π interaction can effectively balance light-emitting efficiency and carrier mobility in organic semiconductor materials, leading to the exploration of novel materials with strong luminescence and fast carrier transport.