Direct ab initio calculation of the dynamical matrix

Marek Hytha; Antonin Simunek

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arXiv · cond-mat/9906236

Direct ab initio calculation of the dynamical matrix

Marek Hytha·Antonin Simunek

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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.

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Marek Hytha, Antonin Simunek. 1999-06-16. Direct ab initio calculation of the dynamical matrix. https://arxiv.org/abs/cond-mat/9906236

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