Colossal Atomic Force Response in van der Waals Materials Arising From Electronic Correlations

TL;DR

This study reveals that many-body van der Waals interactions can cause colossal enhancements in atomic force responses, significantly impacting the understanding of material stability and dynamics.

Contribution

It demonstrates that many-body vdW interactions lead to force responses much larger than pairwise predictions, with implications for complex material behaviors.

Findings

Force response magnitudes exceed pairwise decay by 3-5 orders

Findings confirmed in graphene and carbon nanotubes

Implications for phonon spectra and interfacial adhesion

Abstract

Understanding static and dynamic phenomena in complex materials at different length scales requires reliably accounting for van der Waals (vdW) interactions, which stem from long-range electronic correlations. While the important role of many-body vdW interactions has been extensively documented when it comes to the stability of materials, much less is known about the coupling between vdW interactions and atomic forces. Here we analyze the Hessian force response matrix for a single and two vdW-coupled atomic chains to show that a many-body description of vdW interactions yields atomic force response magnitudes that exceed the expected pairwise decay by 3-5 orders of magnitude for a wide range of separations between the perturbed and the observed atom. Similar findings are confirmed for graphene and carbon nanotubes. This colossal force enhancement suggests implications for phonon spectra, free energies, interfacial adhesion, and collective dynamics in materials with many interacting atoms.