Superhard Semiconducting Phase of Osmium Tetraboride Stabilizing at 11 GPa
2016 (English)In: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 120, no 40, 23165-23171 p.Article in journal (Refereed) Published
Employing a systematic first-principles investigation with crystal structure searching based on an evolutionary algorithm, we have uncovered the, novel phase (P4(2)/nmc) of OsB4 with, a novel superhardness and semiconducting state. In this investigation, metal-to-semiconductor phase transition:is predicted at only a few gigapascals above ambient pressure, i.e, 11 GPa. As a result, the P4(2)/nmc phase, should potentially become a metastable phase at ambient pressure. The Vickers (polycrystalline) hardness and the band gap of the semiconducting phase are calculated to be 60 GPa and 2.90 eV, respectively. These findings indicate that the P4(2)/nmc phase might be a promising superhard-semiconducting material which could be used in cutting and drilling tools, material coating, and other advanced optical technologies. Moreover, under further compression up-to 300 Q-Pa, the semiconducting phase transforms into a metallic P6(3)/mmc phase at 134 GPa, and then another predicted metallic phase with a Circa symmetry emerges beyond 270 GPa. Both dynamic and elastic stabilities are fully investigated to ensure the existence of the predicted phases.
Place, publisher, year, edition, pages
2016. Vol. 120, no 40, 23165-23171 p.
Condensed Matter Physics
IdentifiersURN: urn:nbn:se:uu:diva-307538DOI: 10.1021/acs.jpcc.6b07976ISI: 000385607000044OAI: oai:DiVA.org:uu-307538DiVA: diva2:1047341
FunderSwedish Research Council