CTRAMER: An open source software package for correlating interfacial charge transfer rate constants with donor acceptor geometries in organic photovoltaic materials

TL;DR

This paper introduces CTRAMER, an open source software that combines molecular dynamics, electronic structure calculations, and rate theory to compute charge transfer rates in organic photovoltaic interfaces, facilitating better understanding of device performance.

Contribution

The paper presents a novel integrated software package that combines established methods from multiple disciplines to analyze charge transfer in OPV materials, which is unique and innovative.

Findings

Successfully demonstrated with an example OPV system

Provides tools for analyzing interfacial charge transfer

Facilitates correlation of geometries with rate constants

Abstract

In this paper we present CTRAMER (Charge Transfer RAtes from Molecular dynamics, Electronic structure, and Rate theory), an open source software package for calculating interfacial charge transfer (CT) rate constants in organic photovoltaic (OPV) materials based on ab initio calculations and molecular dynamics simulations. The software is based on identifying representative donor acceptor geometries within interfacial structures obtained from molecular dynamics simulation of donor acceptor blends and calculating the corresponding Fermi s golden rule CT rate constants within the framework of the linearized semiclassical approximation. While the methods used are well established, the integration of these state of the art ideas from different disciplines to study photoinduced CT between excited states and explicit environment, in our opinion, makes this package unique and innovative. The software also provides tools for plotting other observables of interest. After outlining the features and implementation details, usage and performance of the software are demonstrated with results from an example OPV system.