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Updated: Jan 4, 2026
Synthesis of a Thiol Building Block for the Crystallization of a Semiconducting Gyroidal Metal-sulfur Framework
Published on: April 9, 2018
High-pressure synthesis and crystal structure of SrGa4As4
Valentin Weippert1, Dirk Johrendt1
1Ludwig-Maximilians-Universität München, Butenandtstrasse 5-13, D-81377 München, Germany.
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.
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