Direct ab initio calculation of the dynamical matrix

TL;DR

This paper introduces a direct ab initio method for calculating phonon spectra by computing the dynamical matrix from second derivatives of total energy, using pseudopotentials and LDA without iterative procedures, focusing on non-metallic systems.

Contribution

It presents a novel non-iterative approach for ab initio phonon calculations based on second derivatives of total energy, enhancing computational efficiency.

Findings

Method successfully computes phonon spectra for non-metallic systems.

Eliminates the need for iterative self-consistent calculations.

Applicable within the local density approximation using pseudopotentials.

Abstract

In this paper there is presented method for ab initio calculation of the phonon spectra. The method is based upon a direct calculation of the dynamical matrix via second derivatives of the total energy. The pseudopotential technique in plane-wave basis set was used to calculate the total energy within the local density approximation (LDA). For the change of the electron density there is derived the self-consistent equation which is solved analytically with no use of iterations. In this paper the attention is paid only to non-metallic systems.