Excitons in two coupled conjugated polymer chains

TL;DR

This paper investigates exciton states in two coupled conjugated polymer chains, considering Coulomb interactions and chain ordering, revealing distinct exciton features and implications for luminescent polymer experiments.

Contribution

It introduces a detailed model of coupled conjugated chains including Coulomb interactions and analyzes exciton properties for different chain orderings.

Findings

Exciton features differ significantly between parallel and anti-parallel chain orderings.

The model accounts for both intra- and inter-chain Coulomb interactions.

Implications for luminescent polymer experiments are discussed.

Abstract

We have studied the exciton states in two coupled conjugated polymer chains which are modeled individually by the Su-Schrieffer-Heeger Hamiltonian and coupled by an interchain electron-transfer term. Both the intra- and inter-chain long range Coulomb interactions are taken into account. The properties of the lowest symmetric and antisymmetric exciton states are extensively discussed for both the parallel and anti-parallel ordering between these two chains. It is found that, for these two kinds of ordering, the features of excitons are quite different. Possible implications for the experiment of luminescent polymers are also addressed.