Ab-initio investigation of phonon dispersion and anomalies in palladium

TL;DR

This paper presents a high-accuracy ab-initio study of palladium's phonon dispersion, successfully reproducing the Kohn anomaly in the [110] direction without adjustable parameters, advancing understanding of its vibrational properties.

Contribution

First-principles calculations accurately reproduce palladium's phonon dispersion and anomalies, notably the Kohn anomaly, without adjustable parameters.

Findings

Successful reproduction of phonon dispersion in palladium

Identification of the Kohn anomaly in the [110] direction

High-accuracy ab-initio results matching experimental data

Abstract

In recent years, palladium has proven to be a crucial component for devices ranging from nanotube field effect transistors to advanced hydrogen storage devices. In this work, I examine the phonon dispersion of fcc Pd using first principle calculations based on density functional perturbation theory. While several groups in the past have studied the acoustic properties of palladium, this is the first study to reproduce the phonon dispersion and associated anomaly with high accuracy and no adjustable parameters. In particular, I focus on the Kohn anomaly in the [110] direction.