Thermodynamics of anharmonic lattices from first-principles

TL;DR

This paper reviews the development and application of self-consistent phonon theory, especially from first-principles DFT methods, for predicting thermodynamic properties and phase changes in anharmonic lattices.

Contribution

It provides a comprehensive overview of recent implementations of SCP theory based on first-principles calculations and discusses their capabilities in predicting phase transitions and phonon interactions.

Findings

SCP theory can be derived from perturbation or variational approaches.

First-principles DFT methods enhance SCP predictions.

SCP methods can predict phase changes due to phonon softening.

Abstract

Self-consistent phonon (SCP) theory and its application in computing thermodynamic properties of materials are reviewed from a historical perspective. Various more recent implementations based on first-principles electronic structure methods using the density functional theory (DFT) have been discussed. The SCP equations can be derived either from a diagrammatic perturbation theory or a variational approach based on free-energy minimization. These methods can also be used to predict phase change due to phonon softening, and can be extended to study the coupling of phonons to other degrees of freedom in the system.