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Optical Properties of BN in the cubic and in the layered hexagonal phases

Giancarlo Cappellini·Guido Satta·Maurizia Palummo·Giovanni Onida
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Abstract

Linear optical functions of cubic and hexagonal BN have been studied within first principles DFT-LDA theory. Calculated energy-loss functions compare well with experiments and previous theoretical results both for h-BN and for c-BN. Discrepancies arise between theoretical results and experiments in the imaginary part of the dielectric function for c-BN. Possible explanation to this mismatch are proposed and evaluated; lattice constant variations, h-BN contamination in c-BN samples and self-energy effects.

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Giancarlo Cappellini, Guido Satta, Maurizia Palummo, Giovanni Onida. 2001-03-09. Optical Properties of BN in the cubic and in the layered hexagonal phases. https://doi.org/10.1103/physrevb.64.035104

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