Tight binding description of the electronic response of a molecular device to an applied voltage

TL;DR

This paper presents a self-consistent tight binding method to analyze how external electric fields influence the electronic structure of molecular wires and diodes, highlighting the linear voltage dependence of molecular levels.

Contribution

It introduces a computationally efficient tight binding approach that aligns well with ab initio results for studying voltage effects on molecular electronic structures.

Findings

Voltage dependence of molecular levels is mainly linear.

Response to voltage is crucial for device behavior.

Method applicable to various molecules.

Abstract

We analyze the effect of an external electric field on the electronic structure of molecules which have been recently studied as molecular wires or diodes. We use a self-consistent tight binding technique which provides results in good agreement with ab initio calculations and which may be applied to a large number of molecules. The voltage dependence of the molecular levels is mainly linear with slopes intimately related to the electronic structure of the molecules. We emphasize that the response to the applied voltage is an important feature which governs the behavior of a molecular device.