On the Long-Range Exciton Transport in H-Aggregated Heterotriangulene Chains

TL;DR

This paper investigates the potential for long-range exciton transport in heterotriangulene chains, combining theoretical models with structural analysis, and finds that conventional models underestimate the propagation length observed experimentally.

Contribution

It provides a detailed theoretical analysis of exciton transport in heterotriangulene aggregates, highlighting discrepancies with conventional models and suggesting alternative explanations.

Findings

Experimental exciton propagation distances are longer than predicted by standard models.

Structural disorder and decoherence are characterized in detail.

Conventional models underestimate exciton propagation length by about an order of magnitude.

Abstract

Self-assembled aggregates of pigment molecules are potential building blocks for excitonic circuits that find their application in energy conversion and optical signal processing. Recent experimental studies of one-dimensional heterotriangulene supramolecular aggregates suggested that singlet excitons in these structures can propagate on several micron distances. We explore this possibility theoretically by combining electronic structure calculations with microscopic models for exciton transport. Detailed characterization of the structural disorder and exciton decoherence is provided. We argue that conventional exciton transport models give about an order of magnitude shorter estimates for the exciton propagation length which suggest that there are other possible explanations of the experimental results.