Work

Intermolecular Interactions in Molecular Tunnel Junctions: Significant and Still Compatible with the Picture of Single Molecule Junctions in Parallel

Year: 2025

Type: article

Abstract: High Resolution Image Download MS PowerPoint Slide Intermolecular van der Waals (vdW) interactions are inherently present in molecular tunnel junctions fabricated with self-assembled monolayers (SAMs), but characterizing their effects is challenging; current state-of-the-art theory in molecular electronics lacks a dedicated property tailored for this purpose. Based on an analysis that goes beyond the traditional framework and is able to accurately reproduce I–V curves measured on benchmark molecular junctions, we show here that the half-width Λ of the molecular orbital (MO) mediating charge transport is a suitable property for quantifying these vdW effects. Our results demonstrate that vdW interactions prevail over MO–electrode interactions in determining Λ. This contradicts a common claim that the MO width originates from MO–electrode interactions. The present theoretical framework also allows us to solve a conundrum of molecular electronics, namely how and why, despite significant intra-SAM interactions, it is legitimate to describe molecular junctions formed by a bundle of molecules as independent single-molecule junctions in parallel.

Source: JACS Au

DOI: 10.1021/jacsau.5c00927

Authors: Yuhong Chen, Jiajun Feng, Ioan Bâldea, C. Daniel Frisbie, Zuoti Xie

Institutions: Technion – Israel Institute of Technology, Guangdong Technion-Israel Institute of Technology, Heidelberg University, University of Minnesota, Quantum Science Center of Guangdong-Hong Kong-Macao Greater Bay Area

Language: English

Topic: Molecular Junctions and Nanostructures

Subfield: Electrical and Electronic Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: gold

Estimated APC paid: $3,500