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DOE OSTI · 1754258

Materials Data on Y2Ga3(Fe7C)2 by Materials Project

Abstract

Y2Ga3(Fe7C)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Y is bonded in a distorted bent 120 degrees geometry to six Fe, three Ga, and two equivalent C atoms. There are a spread of Y–Fe bond distances ranging from 3.10–3.36 Å. There are two shorter (3.36 Å) and one longer (3.43 Å) Y–Ga bond lengths. Both Y–C bond lengths are 2.54 Å. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded in a 1-coordinate geometry to one Y, ten Fe, and three Ga atoms. There are a spread of Fe–Fe bond distances ranging from 2.36–2.79 Å. There are two shorter (2.69 Å) and one longer (2.70 Å) Fe–Ga bond lengths. In the second Fe site, Fe is bonded to three equivalent Y, seven Fe, and two equivalent Ga atoms to form FeY3Ga2Fe7 cuboctahedra that share corners with four equivalent FeY3Ga2Fe7 cuboctahedra, corners with five GaY2Fe10 cuboctahedra, corners with four equivalent CY2Fe4 octahedra, an edgeedge with one FeY3Ga2Fe7 cuboctahedra, edges with three GaY2Fe10 cuboctahedra, a faceface with one FeY3Ga2Fe7 cuboctahedra, faces with three GaY2Fe10 cuboctahedra, and faces with two equivalent CY2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 63–69°. There are a spread of Fe–Fe bond distances ranging from 2.55–2.66 Å. Both Fe–Ga bond lengths are 2.52 Å. In the third Fe site, Fe is bonded in a single-bond geometry to three Fe, two Ga, and one C atom. The Fe–Fe bond length is 2.62 Å. Both Fe–Ga bond lengths are 2.53 Å. The Fe–C bond length is 1.94 Å. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Y, eight Fe, and two equivalent Ga atoms. Both Fe–Fe bond lengths are 2.54 Å. Both Fe–Ga bond lengths are 2.49 Å. In the fifth Fe site, Fe is bonded in a single-bond geometry to four Fe, two Ga, and one C atom. Both Fe–Ga bond lengths are 2.48 Å. The Fe–C bond length is 1.88 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to two equivalent Y and ten Fe atoms to form distorted GaY2Fe10 cuboctahedra that share corners with four equivalent GaY2Fe10 cuboctahedra, corners with six equivalent FeY3Ga2Fe7 cuboctahedra, edges with two equivalent FeY3Ga2Fe7 cuboctahedra, faces with two equivalent FeY3Ga2Fe7 cuboctahedra, faces with four equivalent GaY2Fe10 cuboctahedra, and faces with four equivalent CY2Fe4 octahedra. In the second Ga site, Ga is bonded to two equivalent Y and ten Fe atoms to form distorted GaY2Fe10 cuboctahedra that share corners with two equivalent FeY3Ga2Fe7 cuboctahedra, corners with four GaY2Fe10 cuboctahedra, corners with two equivalent CY2Fe4 octahedra, edges with two equivalent FeY3Ga2Fe7 cuboctahedra, faces with two equivalent FeY3Ga2Fe7 cuboctahedra, faces with four GaY2Fe10 cuboctahedra, and faces with two equivalent CY2Fe4 octahedra. The corner-sharing octahedral tilt angles are 45°. C is bonded to two equivalent Y and four Fe atoms to form CY2Fe4 octahedra that share corners with two equivalent GaY2Fe10 cuboctahedra, corners with four equivalent FeY3Ga2Fe7 cuboctahedra, corners with two equivalent CY2Fe4 octahedra, faces with two equivalent FeY3Ga2Fe7 cuboctahedra, and faces with four GaY2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 62°.

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2020-06-05. Materials Data on Y2Ga3(Fe7C)2 by Materials Project. https://doi.org/10.17188/1754258

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