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DOE OSTI · 1679269

Materials Data on Er2Fe6Co6P7 by Materials Project

Abstract

Er2Fe6Co6P7 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. there are two inequivalent Er sites. In the first Er site, Er is bonded in a 12-coordinate geometry to three equivalent Fe, six equivalent Co, and six equivalent P atoms. All Er–Fe bond lengths are 3.09 Å. All Er–Co bond lengths are 2.91 Å. All Er–P bond lengths are 2.83 Å. In the second Er site, Er is bonded in a 12-coordinate geometry to six equivalent Fe, six Co, and six equivalent P atoms. All Er–Fe bond lengths are 2.96 Å. There are three shorter (3.06 Å) and three longer (3.20 Å) Er–Co bond lengths. All Er–P bond lengths are 2.84 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded in a 5-coordinate geometry to five P atoms. There are a spread of Fe–P bond distances ranging from 2.27–2.52 Å. In the second Fe site, Fe is bonded to three Er and four P atoms to form distorted FeEr3P4 tetrahedra that share corners with two equivalent CoErP4 tetrahedra, corners with six equivalent FeEr3P4 tetrahedra, edges with two equivalent FeEr3P4 tetrahedra, edges with two equivalent CoErP4 tetrahedra, faces with two equivalent FeEr3P4 tetrahedra, and faces with two equivalent CoErP4 tetrahedra. There are three shorter (2.25 Å) and one longer (2.31 Å) Fe–P bond lengths. There are two inequivalent Co sites. In the first Co site, Co is bonded in a 4-coordinate geometry to three Er and four P atoms. There are a spread of Co–P bond distances ranging from 2.23–2.31 Å. In the second Co site, Co is bonded to one Er and four P atoms to form distorted CoErP4 tetrahedra that share corners with two equivalent FeEr3P4 tetrahedra, corners with six equivalent CoErP4 tetrahedra, edges with two equivalent FeEr3P4 tetrahedra, and faces with two equivalent FeEr3P4 tetrahedra. There are a spread of Co–P bond distances ranging from 2.14–2.28 Å. There are three inequivalent P sites. In the first P site, P is bonded in a 3-coordinate geometry to six equivalent Fe and three equivalent Co atoms. In the second P site, P is bonded in a 9-coordinate geometry to two equivalent Er, three Fe, and four Co atoms. In the third P site, P is bonded in a 9-coordinate geometry to two equivalent Er, four Fe, and three Co atoms.

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2020-06-04. Materials Data on Er2Fe6Co6P7 by Materials Project. https://doi.org/10.17188/1679269

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