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arXiv · 1809.06768

Ab-initio dielectric response function of diamond and other relevant high pressure phases of carbon

Kushal Ramakrishna·Jan Vorberger
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Abstract

The electronic structure and dielectric properties of the diamond, body centered cubic diamond (bc8), and hexagonal diamond (lonsdaleite) phases of carbon are computed using density functional theory and many-body perturbation theory with the emphasis on the excitonic picture of the solid phases relevant in the regimes of high-pressure physics and warm dense matter. We also discuss the capabilities of reproducing the inelastic x-ray scattering spectra in comparison with the existing models in light of recent x-ray scattering experiments on carbon and carbon bearing materials in the Megabar range.

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Kushal Ramakrishna, Jan Vorberger. 2018-09-18. Ab-initio dielectric response function of diamond and other relevant high pressure phases of carbon. https://doi.org/10.1088/1361-648x/ab558e

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