First-principles computation of the Born effective charges and their band-by-band decomposition

Ph. Ghosez; X. Gonze

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First-principles computation of the Born effective charges and their band-by-band decomposition

Ph. Ghosez·X. Gonze

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Abstract

The Born effective charge, Z*, that describes the polarization created by collective atomic displacements, can be computed from first-principles by different techniques. Its band-by-band decomposition appeared recently as a powerful tool for the microscopic characterisation of the bonding in solids. We describe the connections between the different expressions used for the computation of Z*, and analyze the possible associated band-by-band decompositions. We show that unlike for the full Z*, the different band-by-band values are not equal, and emphasize that one of them has an interesting physical meaning.

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Ph. Ghosez, X. Gonze. 1998-05-01. First-principles computation of the Born effective charges and their band-by-band decomposition. https://arxiv.org/abs/cond-mat/9805012

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