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arXiv · 1505.05714

Boron phosphide under pressure: in situ study by Raman scattering and X-ray diffraction

Vladimir L. Solozhenko·Oleksandr O. Kurakevych·Yann Le Godec·Aleksandr V. Kurnosov·Artem R. Oganov
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Abstract

Cubic boron phosphide BP has been studied in situ by X-ray diffraction and Raman scattering up to 55 GPa at 300 K in a diamond anvil cell. The bulk modulus of B0 = 174(2) GPa has been established, which is in excellent agreement with our ab initio calculations. The data on Raman shift as a function of pressure, combined with equation-of-state data, allowed us to estimate the Grüneisen parameters of the TO and LO modes of zinc-blende structure, γGTO = 1.16 and γGLO = 1.04, just like in the case of other AIIIBV diamond-like phases, for which γGTO > γGLO = 1. We also established that the pressure dependence of the effective electro-optical constant α is responsible for a strong change in relative intensities of the TO and LO modes from ITO/ILO ~0.25 at 0.1 MPa to ITO/ILO ~2.5 at 45 GPa, for which we also find excellent agreement between experiment and theory.

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Vladimir L. Solozhenko, Oleksandr O. Kurakevych, Yann Le Godec, Aleksandr V. Kurnosov, Artem R. Oganov. 2015-05-21. Boron phosphide under pressure: in situ study by Raman scattering and X-ray diffraction. https://doi.org/10.1063/1.4890231

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