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DOE OSTI · 1730806

Materials Data on Eu2Ni7P4 by Materials Project

Abstract

Eu2Ni7P4 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. there are two inequivalent Eu2+ sites. In the first Eu2+ site, Eu2+ is bonded to six P3- atoms to form distorted EuP6 pentagonal pyramids that share corners with eight NiP4 tetrahedra, corners with two equivalent EuP5 trigonal bipyramids, edges with nine NiP4 tetrahedra, an edgeedge with one EuP5 trigonal bipyramid, and faces with two equivalent EuP6 pentagonal pyramids. There are a spread of Eu–P bond distances ranging from 2.87–2.94 Å. In the second Eu2+ site, Eu2+ is bonded to five P3- atoms to form distorted EuP5 trigonal bipyramids that share corners with two equivalent EuP6 pentagonal pyramids, corners with seven NiP4 tetrahedra, corners with four equivalent EuP5 trigonal bipyramids, an edgeedge with one EuP6 pentagonal pyramid, edges with six NiP4 tetrahedra, and edges with two equivalent EuP5 trigonal bipyramids. There are a spread of Eu–P bond distances ranging from 2.97–3.06 Å. There are seven inequivalent Ni+1.14+ sites. In the first Ni+1.14+ site, Ni+1.14+ is bonded to four P3- atoms to form NiP4 tetrahedra that share corners with four equivalent EuP6 pentagonal pyramids, corners with eight NiP4 tetrahedra, a cornercorner with one EuP5 trigonal bipyramid, an edgeedge with one EuP6 pentagonal pyramid, edges with two equivalent NiP4 tetrahedra, and edges with two equivalent EuP5 trigonal bipyramids. There are one shorter (2.27 Å) and three longer (2.38 Å) Ni–P bond lengths. In the second Ni+1.14+ site, Ni+1.14+ is bonded in a trigonal non-coplanar geometry to three P3- atoms. There are one shorter (2.16 Å) and two longer (2.33 Å) Ni–P bond lengths. In the third Ni+1.14+ site, Ni+1.14+ is bonded to four P3- atoms to form NiP4 tetrahedra that share corners with eleven NiP4 tetrahedra, corners with two equivalent EuP5 trigonal bipyramids, edges with two equivalent EuP6 pentagonal pyramids, and edges with three equivalent EuP5 trigonal bipyramids. There are a spread of Ni–P bond distances ranging from 2.32–2.48 Å. In the fourth Ni+1.14+ site, Ni+1.14+ is bonded to four P3- atoms to form NiP4 tetrahedra that share corners with two equivalent EuP6 pentagonal pyramids, corners with nine NiP4 tetrahedra, corners with two equivalent EuP5 trigonal bipyramids, edges with three equivalent EuP6 pentagonal pyramids, and edges with two equivalent NiP4 tetrahedra. There are a spread of Ni–P bond distances ranging from 2.29–2.38 Å. In the fifth Ni+1.14+ site, Ni+1.14+ is bonded to four P3- atoms to form NiP4 tetrahedra that share corners with two equivalent EuP6 pentagonal pyramids, corners with six NiP4 tetrahedra, corners with two equivalent EuP5 trigonal bipyramids, edges with three equivalent EuP6 pentagonal pyramids, edges with four NiP4 tetrahedra, and an edgeedge with one EuP5 trigonal bipyramid. There are a spread of Ni–P bond distances ranging from 2.29–2.38 Å. In the sixth Ni+1.14+ site, Ni+1.14+ is bonded in a trigonal non-coplanar geometry to three P3- atoms. There are one shorter (2.20 Å) and two longer (2.34 Å) Ni–P bond lengths. In the seventh Ni+1.14+ site, Ni+1.14+ is bonded in a trigonal non-coplanar geometry to three P3- atoms. There are one shorter (2.18 Å) and two longer (2.30 Å) Ni–P bond lengths. There are four inequivalent P3- sites. In the first P3- site, P3- is bonded in a 9-coordinate geometry to four Eu2+ and five Ni+1.14+ atoms. In the second P3- site, P3- is bonded in a 9-coordinate geometry to three equivalent Eu2+ and six Ni+1.14+ atoms. In the third P3- site, P3- is bonded in a 9-coordinate geometry to two equivalent Eu2+ and seven Ni+1.14+ atoms. In the fourth P3- site, P3- is bonded in a 9-coordinate geometry to two equivalent Eu2+ and seven Ni+1.14+ atoms.

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2020-04-29. Materials Data on Eu2Ni7P4 by Materials Project. https://doi.org/10.17188/1730806

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