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DOE OSTI · 1305794

Materials Data on Er2Co12P7 by Materials Project

Abstract

Er2Co12P7 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. there are two inequivalent Er3+ sites. In the first Er3+ site, Er3+ is bonded to six equivalent P3- atoms to form distorted ErP6 pentagonal pyramids that share corners with twelve CoP4 tetrahedra, corners with six equivalent CoP5 trigonal bipyramids, edges with nine CoP4 tetrahedra, edges with three equivalent CoP5 trigonal bipyramids, and faces with two equivalent ErP6 pentagonal pyramids. All Er–P bond lengths are 2.82 Å. In the second Er3+ site, Er3+ is bonded to six equivalent P3- atoms to form distorted ErP6 pentagonal pyramids that share corners with twelve CoP4 tetrahedra, corners with six equivalent CoP5 trigonal bipyramids, edges with twelve CoP4 tetrahedra, and faces with two equivalent ErP6 pentagonal pyramids. All Er–P bond lengths are 2.84 Å. There are four inequivalent Co+1.25+ sites. In the first Co+1.25+ site, Co+1.25+ is bonded to four P3- atoms to form CoP4 tetrahedra that share corners with four ErP6 pentagonal pyramids, corners with ten CoP4 tetrahedra, corners with two equivalent CoP5 trigonal bipyramids, an edgeedge with one ErP6 pentagonal pyramid, edges with three CoP4 tetrahedra, and edges with four equivalent CoP5 trigonal bipyramids. There are a spread of Co–P bond distances ranging from 2.13–2.27 Å. In the second Co+1.25+ site, Co+1.25+ is bonded to four P3- atoms to form CoP4 tetrahedra that share corners with two equivalent ErP6 pentagonal pyramids, corners with ten CoP4 tetrahedra, corners with four equivalent CoP5 trigonal bipyramids, edges with three ErP6 pentagonal pyramids, edges with four CoP4 tetrahedra, and an edgeedge with one CoP5 trigonal bipyramid. There are a spread of Co–P bond distances ranging from 2.24–2.30 Å. In the third Co+1.25+ site, Co+1.25+ is bonded to five P3- atoms to form distorted CoP5 trigonal bipyramids that share corners with four ErP6 pentagonal pyramids, corners with eight CoP4 tetrahedra, corners with four equivalent CoP5 trigonal bipyramids, an edgeedge with one ErP6 pentagonal pyramid, edges with seven CoP4 tetrahedra, and edges with four equivalent CoP5 trigonal bipyramids. There are a spread of Co–P bond distances ranging from 2.23–2.56 Å. In the fourth Co+1.25+ site, Co+1.25+ is bonded to four P3- atoms to form CoP4 tetrahedra that share corners with two equivalent ErP6 pentagonal pyramids, corners with twelve CoP4 tetrahedra, corners with two equivalent CoP5 trigonal bipyramids, edges with three ErP6 pentagonal pyramids, edges with three CoP4 tetrahedra, and edges with two equivalent CoP5 trigonal bipyramids. There are a spread of Co–P bond distances ranging from 2.23–2.29 Å. There are three inequivalent P3- sites. In the first P3- site, P3- is bonded in a 3-coordinate geometry to nine Co+1.25+ atoms. In the second P3- site, P3- is bonded in a 9-coordinate geometry to two equivalent Er3+ and seven Co+1.25+ atoms. In the third P3- site, P3- is bonded in a 9-coordinate geometry to two equivalent Er3+ and seven Co+1.25+ atoms.

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2020-07-17. Materials Data on Er2Co12P7 by Materials Project. https://doi.org/10.17188/1305794

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