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In-Cage Interactions in the Clathrate Superconductor Sr8 Si46.

ABSTRACT: The clathrate?I superconductor Sr8 Si46 is obtained under high-pressure high-temperature conditions, at 5?GPa and temperatures in the range of 1273 to 1373?K. At ambient pressure, the compound decomposes upon heating at T=796(5)?K into Si and SrSi2 . The crystal structure of the clathrate is isotypic to that of Na8 Si46 . Chemical bonding analysis reveals conventional covalent bonding within the silicon network as well as additional multi-atomic interactions between Sr and Si within the framework cages. Physical measurements indicate a bulk BCS type?II superconducting state below Tc =3.8(3)?K.

SUBMITTER: Hubner JM

PROVIDER: S-EPMC7004181 | biostudies-literature | 2020 Jan

REPOSITORIES: biostudies-literature

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In-Cage Interactions in the Clathrate Superconductor Sr8 Si46.

Hübner Julia-Maria JM Prots Yurii Y Schnelle Walter W Bobnar Matej M König Markus M Baitinger Michael M Simon Paul P Carrillo-Cabrera Wilder W Ormeci Alim A Svanidze Eteri E Grin Yuri Y Schwarz Ulrich U

Chemistry (Weinheim an der Bergstrasse, Germany) 20191212 4

The clathrate I superconductor Sr8 Si46 is obtained under high-pressure high-temperature conditions, at 5 GPa and temperatures in the range of 1273 to 1373 K. At ambient pressure, the compound decomposes upon heating at T=796(5) K into Si and SrSi2 . The crystal structure of the clathrate is isotypic to that of Na8 Si46 . Chemical bonding analysis reveals conventional covalent bonding within the silicon network as well as additional multi-at ...[more]

PMID: 31652015

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