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Cage Adaption by High-Pressure Synthesis: The Clathrate-I Borosilicide Rb₈B₈Si₃₈.

ABSTRACT: Rb₈B₈Si₃₈ forms under high-pressure, high-temperature conditions at p = 8 GPa and T = 1273 K. The new compound (space group Pm3?n, a = 9.9583(1) Å) is the second example for a clathrate-I borosilicide. The phase is inert against strong acids and bases and thermally stable up to 1300 K at ambient pressure. (Rb⁺)₈(B^-)₈(Si⁰)₃₈ is electronically balanced, diamagnetic, and shows semiconducting behavior with moderate Seebeck coefficient below 300 K. Chemical bonding analysis by the electron localizability approach confirms the description of Rb₈B₈Si₃₈ as Zintl phase.

SUBMITTER: Hubner JM

PROVIDER: S-EPMC7887739 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature

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Cage Adaption by High-Pressure Synthesis: The Clathrate-I Borosilicide Rb8B8Si38.

Hübner Julia-Maria JM Jung Walter W Schmidt Marcus M Bobnar Matej M Koželj Primož P Böhme Bodo B Baitinger Michael M Etter Martin M Grin Yuri Y Schwarz Ulrich U

Inorganic chemistry 20201026 4

Rb8B8Si38 forms under high-pressure, high-temperature conditions at p = 8 GPa and T = 1273 K. The new compound (space group Pm3̅n, a = 9.9583(1) Å) is the second example for a clathrate-I borosilicide. The phase is inert against strong acids and bases and thermally stable up to 1300 K at ambient pressure. (Rb+)8(B-)8(Si0)38 is electronically balanced, diamagnetic, ...[more]

PMID: 33104343

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