Issue 5, 2017

Polaron dynamics in anisotropic Holstein–Peierls systems

Abstract

Polaron dynamics in anisotropic organic molecular semiconductors is theoretically investigated and simulated in the framework of a semi-classical Holstein–Peierls model. Our computational protocol is presented and applied to studies of a two-dimensional molecular crystal. The intermolecular (Peierls) parameters for a particular crystal direction are systematically changed in order to study the effect of anisotropy in the system. The usefulness of this methodology is highlighted by studying the polaron dynamics on a picosecond timescale, which provides a microscopic insight into the influence of the interplay between different intramolecular parameters on the charge transport mechanism. Our results show that the polaron mobility is substantially reduced in going from an anisotropic to an isotropic relationship between the Peierls parameters for different directions in the crystal. Interestingly, the molecular charge distribution presents three different signatures corresponding to a one-dimensional polaron, a two-dimensional polaron, and an intermediate state for which the polaron localization depends on the degree of anisotropy. Importantly, the two-dimensional polaron, which is present in the essentially isotropic system, is immobile whereas the other two types of polarons are mobile. This, in order for polaron transport to occur in a two-dimensional molecular based system, this system has to be anisotropic.

Graphical abstract: Polaron dynamics in anisotropic Holstein–Peierls systems

Article information

Article type
Paper
Submitted
01 Nov 2016
Accepted
04 Jan 2017
First published
04 Jan 2017

Phys. Chem. Chem. Phys., 2017,19, 4078-4084

Polaron dynamics in anisotropic Holstein–Peierls systems

L. A. Ribeiro Junior and S. Stafström, Phys. Chem. Chem. Phys., 2017, 19, 4078 DOI: 10.1039/C6CP07478B

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements