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DOE OSTI · 1272400

Materials Data on SrZnO2 by Materials Project

Abstract

SrZnO2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Sr2+ is bonded to seven O2- atoms to form distorted SrO7 pentagonal bipyramids that share corners with four equivalent SrO7 pentagonal bipyramids, corners with four equivalent ZnO4 tetrahedra, edges with four equivalent SrO7 pentagonal bipyramids, edges with five equivalent ZnO4 tetrahedra, and faces with two equivalent SrO7 pentagonal bipyramids. There are a spread of Sr–O bond distances ranging from 2.60–2.70 Å. Zn2+ is bonded to four O2- atoms to form ZnO4 tetrahedra that share corners with four equivalent SrO7 pentagonal bipyramids, corners with four equivalent ZnO4 tetrahedra, and edges with five equivalent SrO7 pentagonal bipyramids. There are a spread of Zn–O bond distances ranging from 1.97–2.08 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Sr2+ and two equivalent Zn2+ atoms to form distorted OSr3Zn2 square pyramids that share corners with eight equivalent OSr4Zn2 octahedra, edges with four equivalent OSr4Zn2 octahedra, and edges with four equivalent OSr3Zn2 square pyramids. The corner-sharing octahedra tilt angles range from 27–62°. In the second O2- site, O2- is bonded to four equivalent Sr2+ and two equivalent Zn2+ atoms to form distorted OSr4Zn2 octahedra that share corners with four equivalent OSr4Zn2 octahedra, corners with eight equivalent OSr3Zn2 square pyramids, edges with two equivalent OSr4Zn2 octahedra, edges with four equivalent OSr3Zn2 square pyramids, and faces with two equivalent OSr4Zn2 octahedra. The corner-sharing octahedral tilt angles are 62°.

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2020-07-14. Materials Data on SrZnO2 by Materials Project. https://doi.org/10.17188/1272400

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