The p-sc structure in phosphorus: bringing order to the high pressure phases of group 15 elements.

ABSTRACT: Black phosphorus was studied by state-of-the-art synchrotron X-ray diffraction in a Diamond Anvil Cell during room temperature compression in the presence of He, H2, N2 and Daphne Oil 7474. The data demonstrate that the existence of the pseudo simple-cubic (p-sc) structure above 10.5 GPa is an intrinsic feature of P independent from the pressure transmitting medium. In the case of He, the pressure evolution of the lattice parameters and unit cell volume of P across the A17, A7 and p-sc structures was obtained and the corresponding EOS derived, providing a deeper insight on the recently reported p-sc structure. The results presented in this letter highlight the key role of the s-p orbital mixing in the formation and stabilization of the p-sc structure up to ?30 GPa, solving apparent contradictions emerging from previous literature and finally bringing order to the sequence of the high pressure A7 layered structure in group 15 elements.

SUBMITTER: Scelta D 

PROVIDER: S-EPMC6146374 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature