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DOE OSTI · 1710682

Materials Data on HfCrGa2 by Materials Project

Abstract

HfCrGa2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Hf sites. In the first Hf site, Hf is bonded in a 12-coordinate geometry to four Cr and eight Ga atoms. There are a spread of Hf–Cr bond distances ranging from 3.03–3.16 Å. There are a spread of Hf–Ga bond distances ranging from 2.82–3.02 Å. In the second Hf site, Hf is bonded in a 7-coordinate geometry to six Cr and seven Ga atoms. There are a spread of Hf–Cr bond distances ranging from 3.12–3.28 Å. There are a spread of Hf–Ga bond distances ranging from 2.78–2.98 Å. There are two inequivalent Cr sites. In the first Cr site, Cr is bonded in a 12-coordinate geometry to five Hf, one Cr, and six Ga atoms. The Cr–Cr bond length is 2.53 Å. There are a spread of Cr–Ga bond distances ranging from 2.46–2.68 Å. In the second Cr site, Cr is bonded to four Hf, two equivalent Cr, and six Ga atoms to form distorted face-sharing CrHf4Cr2Ga6 cuboctahedra. There are a spread of Cr–Ga bond distances ranging from 2.50–2.67 Å. There are five inequivalent Ga sites. In the first Ga site, Ga is bonded in a 11-coordinate geometry to five Hf, two equivalent Cr, and four Ga atoms. There are a spread of Ga–Ga bond distances ranging from 2.58–2.95 Å. In the second Ga site, Ga is bonded in a 11-coordinate geometry to five Hf, two equivalent Cr, and four Ga atoms. There are one shorter (2.84 Å) and two longer (2.98 Å) Ga–Ga bond lengths. In the third Ga site, Ga is bonded in a 7-coordinate geometry to three Hf, four Cr, and one Ga atom. In the fourth Ga site, Ga is bonded in a 8-coordinate geometry to four Hf, four Cr, and one Ga atom. In the fifth Ga site, Ga is bonded in a 6-coordinate geometry to three Hf, three Cr, and two Ga atoms.

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2020-06-05. Materials Data on HfCrGa2 by Materials Project. https://doi.org/10.17188/1710682

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36 MATERIALS SCIENCE↗