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Band-by-band decomposition of the Born effective charges

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 following different techniques. We establish the connections existing between these different formulations, and analyze the related 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 a natural physical meaning in terms of Wannier functions.

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Ph. Ghosez, X. Gonze. 2000-11-13. Band-by-band decomposition of the Born effective charges. https://doi.org/10.1088/0953-8984%2F12%2F43%2F308

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