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Discovery of new boron-rich chalcogenides: orthorhombic B₆X (X=S, Se).

ABSTRACT: New boron-rich sulfide B₆S and selenide B₆Se have been discovered by combination of high pressure - high temperature synthesis and ab initio evolutionary crystal structure prediction, and studied by synchrotron X-ray diffraction and Raman spectroscopy at ambient conditions. As it follows from Rietveld refinement of powder X-ray diffraction data, both chalcogenides have orthorhombic symmetry and belong to Pmna space group. All experimentally observed Raman bands have been attributed to the theoretically calculated phonon modes, and the mode assignment has been performed. Prediction of mechanical properties (hardness and elastic moduli) of new boron-rich chalcogenides has been made using ab initio calculations, and both compounds were found to be members of a family of hard phases.

SUBMITTER: Cherednichenko KA

PROVIDER: S-EPMC7283469 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Discovery of new boron-rich chalcogenides: orthorhombic B6X (X=S, Se).

Cherednichenko Kirill A KA Mukhanov Vladimir A VA Wang Zhenhai Z Oganov Artem R AR Kalinko Aleksandr A Dovgaliuk Iurii I Solozhenko Vladimir L VL

Scientific reports 20200609 1

New boron-rich sulfide B6S and selenide B6Se have been discovered by combination of high pressure - high temperature synthesis and ab initio evolutionary crystal structure prediction, and studied by synchrotron X-ray diffraction and Raman spectroscopy at ambient conditions. As it follows from Rietveld refinement of powder X-ray diffraction data, both chalcogenides have orthorhombic symmetry and belong to Pmna space group. All experimentally observed Raman bands have been at ...[more]

PMID: 32518269

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