Effect of Anchoring Groups on the Conduction Properties of Phenyl Based on Organic Molecules Connected to Copper Leads

TL;DR

This study investigates how different anchoring groups, sulfur and nitrogen, affect the electronic conductance of phenyl-based organic molecules connected to copper leads, revealing that amine groups significantly enhance conductance.

Contribution

It introduces a combined NEGF and DFTB computational approach to analyze the impact of anchoring groups on molecular conductance, highlighting the superior performance of amine groups.

Findings

Amine groups increase conductance by about ten times compared to thiol groups.

The NEGF-DFTB method effectively models electronic transport in molecular devices.

Anchoring groups critically influence the conduction properties of phenyl-based molecules.

Abstract

We report equilibrium and non-equilibrium conductance of terphenyl molecules with different anchoring groups including sulfur and nitrogen atom. The corresponding molecules are terphenyl-dithiols(TPDT) and diamino-terphenyl(DATP). The non-equilibrium Green's function (NEGF) technique has been implemented on the density functional tight-binding (DFTB) code to perform computations of the electronic transport properties of molecular devices. The NEGFs are used to compute the electronic density self-consistently with open boundary condition naturally encountered in transport problem which is imposed by the potentials at the contacts. As result, the value of the molecular conductance with amine groups is higher about ten times than the thiol anchored group