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DOE OSTI · 1726805

Materials Data on Sc7Cr5Ge9 by Materials Project

Abstract

Sc7Cr5Ge9 crystallizes in the orthorhombic Fmmm space group. The structure is three-dimensional. there are four inequivalent Sc sites. In the first Sc site, Sc is bonded in a 9-coordinate geometry to two equivalent Cr and seven Ge atoms. Both Sc–Cr bond lengths are 2.87 Å. There are a spread of Sc–Ge bond distances ranging from 2.85–3.20 Å. In the second Sc site, Sc is bonded in a 7-coordinate geometry to seven Ge atoms. There are a spread of Sc–Ge bond distances ranging from 2.61–2.99 Å. In the third Sc site, Sc is bonded to seven Ge atoms to form distorted ScGe7 pentagonal bipyramids that share an edgeedge with one ScGe7 pentagonal bipyramid and faces with two equivalent ScCrGe6 pentagonal bipyramids. There are a spread of Sc–Ge bond distances ranging from 2.63–2.97 Å. In the fourth Sc site, Sc is bonded to one Cr and six Ge atoms to form distorted ScCrGe6 pentagonal bipyramids that share an edgeedge with one ScCrGe6 pentagonal bipyramid and faces with two equivalent ScGe7 pentagonal bipyramids. The Sc–Cr bond length is 2.77 Å. There are a spread of Sc–Ge bond distances ranging from 2.64–2.97 Å. There are two inequivalent Cr sites. In the first Cr site, Cr is bonded in a 11-coordinate geometry to three Sc, four equivalent Cr, and four Ge atoms. All Cr–Cr bond lengths are 2.70 Å. There are two shorter (2.48 Å) and two longer (2.57 Å) Cr–Ge bond lengths. In the second Cr site, Cr is bonded in a 6-coordinate geometry to one Cr and six Ge atoms. There are a spread of Cr–Ge bond distances ranging from 2.53–2.81 Å. There are six inequivalent Ge sites. In the first Ge site, Ge is bonded in a 9-coordinate geometry to four Sc, four equivalent Cr, and one Ge atom. The Ge–Ge bond length is 2.51 Å. In the second Ge site, Ge is bonded in a 9-coordinate geometry to nine Sc atoms. In the third Ge site, Ge is bonded in a 8-coordinate geometry to four equivalent Sc and four equivalent Cr atoms. In the fourth Ge site, Ge is bonded in a 10-coordinate geometry to six Sc, two equivalent Cr, and two Ge atoms. There are one shorter (2.57 Å) and one longer (2.66 Å) Ge–Ge bond lengths. In the fifth Ge site, Ge is bonded in a 10-coordinate geometry to six Sc, three Cr, and one Ge atom. The Ge–Ge bond length is 2.77 Å. In the sixth Ge site, Ge is bonded in a 11-coordinate geometry to three Sc, six Cr, and two equivalent Ge atoms.

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2020-06-04. Materials Data on Sc7Cr5Ge9 by Materials Project. https://doi.org/10.17188/1726805

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