Peierls Instability and Electron-Phonon Coupling in a One-dimensional Sodium Wire

TL;DR

This study investigates Peierls instability and electron-phonon interactions in a one-dimensional sodium wire using first-principles calculations, revealing structural distortions and weak dimerization related to electron-phonon coupling.

Contribution

It provides a detailed first-principles analysis of Peierls instability in sodium wires, highlighting the role of electron-phonon coupling in structural transitions.

Findings

Na wire remains stable in a linear form over a range of distances

At small distances, the wire adopts a zigzag distortion

Near breaking point, the wire exhibits weak Peierls dimerization

Abstract

We have studied Peierls instability in an atomically thin wire of sodium atoms using first-principles density-functional methods. A Na wire has a stable uniform linear structure over a range of inter-atomic distances. At smaller inter-atomic distances it develops a zigzag distortion. At larger inter-atomic distances, just before breaking, a Na wire undergoes a very weak Peierls dimerization. This behavior of a Na wire is understood in terms of its electron-phonon coupling properties.