A Borosilicide with Clathrate VIII Structure.

ABSTRACT: The high-pressure phase Na₈B_xSi_46-x (3 < x < 5) is the first representative of a borosilicide crystallizing in the rarely occurring clathrate VIII type structure. Crystals with composition Na₈B₄Si₄₂ (space group I43̅m; a = 9.7187(2) Å; Pearson symbol cI54) were obtained at 5-8 GPa and 1200 K. The clathrate I modification exists for the same composition at lower pressure with a larger cell volume (Pm3̅n; a = 9. 977(2) Å; cP54). Profound structural adaptions allow for a higher density of the clathrate VIII type than clathrate I, opening up the perspective of obtaining clathrate VIII type compounds as high-pressure forms of clathrate I.

SUBMITTER: Hubner JM 

PROVIDER: S-EPMC9377393 | biostudies-literature | 2022 Aug

REPOSITORIES: biostudies-literature