Heat conduction across molecular junctions between nanoparticles

TL;DR

This study uses molecular dynamics simulations to analyze heat conduction through molecular junctions between nanoparticles, revealing environment-dependent conductance behaviors and spectral overlap effects.

Contribution

It provides new insights into how the environment and vibrational spectrum overlap influence heat conductance in nanoparticle junctions.

Findings

Conductance in vacuum is length-independent but spectrum-sensitive.

In liquid, conductance remains constant up to a crossover length.

A Fourier regime emerges at larger lengths in liquid environments.

Abstract

We investigate the problem of heat conduction across a molecular junction connecting two nanoparticles, both in vacuum and in a liquid environment, using classical molecular dynamics simulations. In vacuum, the well-known result of a length independent conductance is recovered; its precise value, however, is found to depend sensitively on the overlap between the vibrational spectrum of the junction and the density of states of the nanoparticles that act as thermal contacts. In a liquid environment, the conductance is constant up to a crossover length, above which a standard Fourier regime is recovered.