Tunnelling in alkanes anchored to gold electrodes via amine end groups

TL;DR

This study investigates electron transport in alkane chains with amine end groups bonded to gold electrodes, providing theoretical insights that align well with recent experimental findings and highlighting differences from thiol-based systems.

Contribution

It offers a detailed theoretical analysis of amine-gold bonding and electron transport in alkane junctions, expanding understanding beyond thiol-based systems.

Findings

Good agreement with experimental conductance data for alkane diamines

Identifies key differences between amine and thiol bonding in electron transport

Provides insights into molecular junction conductance mechanisms

Abstract

For investigation of electron transport on the nanoscale, a system possessing a simple to interpret electronic structure is composed of alkane chains bridging two electrodes via end groups; to date the majority of experiments and theoretical investigations on such structures have considered thiols bonding to gold electrodes. Recently experiments show that well defined molecular conductances may be resolved if the thiol end groups are replaced by amines. In this theoretical study, we investigate the bonding of amine groups to gold clusters and calculate electron transport across the resulting tunnel junctions. We find very good agreement with recent experiments for alkane diamines and discuss differences with respect to the alkane dithiol system.