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High-pressure synthesis and crystal structure of SrGa4As4.

ABSTRACT: Strontium tetra-gallate(II,III) tetra-arsenide, SrGa4As4, was synthesized in a Walker-type multianvil apparatus under high-pressure/high-temperature conditions of 8?GPa and 1573?K. The com-pound crystallizes in a new structure type (P3221, Z = 3) as a three-dimensional (3D) framework of corner-sharing SrAs8 quadratic anti-prisms with strontium situated on a twofold rotation axis (Wyckoff position 3b). This arrangement is surrounded by a 3D framework which can be described as alternately stacked layers of either condensed GaIIIAs4 tetra-hedra or honeycomb-like layers built up from distorted ethane-like GaII 2As6 units com-prising Ga-Ga bonds.

SUBMITTER: Weippert V

PROVIDER: S-EPMC6829736 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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High-pressure synthesis and crystal structure of SrGa4As4.

Weippert Valentin V Johrendt Dirk D

Acta crystallographica. Section E, Crystallographic communications 20191022 Pt 11

Strontium tetra-gallate(II,III) tetra-arsenide, SrGa4As4, was synthesized in a Walker-type multianvil apparatus under high-pressure/high-temperature conditions of 8 GPa and 1573 K. The com-pound crystallizes in a new structure type (P3221, Z = 3) as a three-dimensional (3D) framework of corner-sharing SrAs8 quadratic anti-prisms with strontium situated on a twofold rotation axis (Wyckoff position 3b). This arrangement is surrounded ...[more]

PMID: 31709083

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