A Molecular Platinum Cluster Junction: A Single-Molecule Switch

TL;DR

This paper theoretically investigates a single-molecule junction with a platinum cluster, revealing high conductance and switchable states due to quantum interference effects near the Fermi level.

Contribution

It introduces a novel platinum cluster-based molecular junction with unique electronic switching properties and explains the underlying quantum interference mechanisms.

Findings

High conductance at the Fermi level

Two distinct high on/off switching states

Degenerate HOMO orbitals cause quantum interference

Abstract

We present a theoretical study of the electronic transport through single-molecule junctions incorporating a Pt6 metal cluster bound within an organic framework. We show that the insertion of this molecule between a pair of electrodes leads to a fully atomically engineered nano-metallic device with high conductance at the Fermi level and two sequential high on/off switching states. The origin of this property can be traced back to the existence of a HOMO which consists of two degenerate and asymmetric orbitals, lying close in energy to the Fermi level of the metallic leads. Their degeneracy is broken when the molecule is contacted to the leads, giving rise to two resonances which become pinned close to the Fermi level and display destructive interference.