Voltage induced conformational changes and current control in charge transfer through molecules

TL;DR

This paper investigates how voltage-induced conformational changes in molecules influence charge transfer, revealing voltage-dependent energy surfaces that cause abrupt structural shifts and enable current control, with potential applications in molecular rotors.

Contribution

It introduces a theoretical framework showing how voltage can induce conformational changes in molecules, affecting charge transfer and enabling control over molecular electronic states.

Findings

Voltage-dependent energy surfaces cause conformational shifts.

Current plateaus are linked to molecular conformational states.

Bias and gate voltages can control charge transfer and trigger molecular rotation.

Abstract

Transport through molecular contacts with a sluggish intramolecular vibrational mode strongly coupled to excess charges is studied far from equilibrium. A Born-Oppenheimer approximation in steady state reveals voltage dependent energy surfaces which cause abrupt conformational changes of the molecular backbone. These are directly related to transitions between current plateaus which are relatively robust against thermal fluctuations and appear in patterns reminiscent of Coulomb diamonds. In a regime accessible in experiments bias and gate voltages allow for an efficient control of charge transfer or may trigger a molecular rotor.