Vibrational nonequilibrium effects in the conductance of single-molecules with multiple electronic states

TL;DR

This paper investigates how vibrational nonequilibrium effects influence charge transport in single-molecule junctions with multiple electronic states, revealing complex vibronic interactions that affect conductance and stability.

Contribution

It introduces a detailed analysis of vibrational nonequilibrium effects in molecular junctions with multiple electronic states using master equation and Green's function methods.

Findings

Vibrational nonequilibrium significantly affects conductance.

Electronic-vibrational coupling induces vibronic emission and absorption.

Theoretical models elucidate conductance behavior in specific molecular junctions.

Abstract

Vibrational nonequilibrium effects in charge transport through single-molecule junctions are investigated. Focusing on molecular bridges with multiple electronic states, it is shown that electronic-vibrational coupling triggers a variety of vibronic emission and absorption processes, which influence the conductance properties and mechanical stability of single-molecule junctions profoundly. Employing a master equation and a nonequilibrium Green's function approach, these processes are analyzed in detail for a generic model of a molecular junction and for benzenedibutanethiolate bound to gold electrodes.