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DOE OSTI · 1264894

Materials Data on Nd2Ni7P4 by Materials Project

Abstract

Nd2Ni7P4 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. there are two inequivalent Nd+2.50+ sites. In the first Nd+2.50+ site, Nd+2.50+ is bonded to five P3- atoms to form distorted NdP5 trigonal bipyramids that share corners with two equivalent NdP6 pentagonal pyramids, corners with seven NiP4 tetrahedra, corners with four equivalent NdP5 trigonal bipyramids, an edgeedge with one NdP6 pentagonal pyramid, edges with six NiP4 tetrahedra, and edges with two equivalent NdP5 trigonal bipyramids. There are a spread of Nd–P bond distances ranging from 2.98–3.04 Å. In the second Nd+2.50+ site, Nd+2.50+ is bonded to six P3- atoms to form distorted NdP6 pentagonal pyramids that share corners with eight NiP4 tetrahedra, corners with two equivalent NdP5 trigonal bipyramids, edges with nine NiP4 tetrahedra, an edgeedge with one NdP5 trigonal bipyramid, and faces with two equivalent NdP6 pentagonal pyramids. There are a spread of Nd–P bond distances ranging from 2.89–2.95 Å. There are seven inequivalent Ni1+ sites. In the first Ni1+ site, Ni1+ is bonded in a trigonal non-coplanar geometry to three P3- atoms. There are one shorter (2.19 Å) and two longer (2.34 Å) Ni–P bond lengths. In the second Ni1+ site, Ni1+ is bonded in a trigonal non-coplanar geometry to three P3- atoms. There are one shorter (2.14 Å) and two longer (2.32 Å) Ni–P bond lengths. In the third Ni1+ site, Ni1+ is bonded in a trigonal non-coplanar geometry to three P3- atoms. There are one shorter (2.17 Å) and two longer (2.32 Å) Ni–P bond lengths. In the fourth Ni1+ site, Ni1+ is bonded to four P3- atoms to form NiP4 tetrahedra that share corners with two equivalent NdP6 pentagonal pyramids, corners with nine NiP4 tetrahedra, corners with two equivalent NdP5 trigonal bipyramids, edges with three equivalent NdP6 pentagonal pyramids, and edges with two equivalent NiP4 tetrahedra. There are a spread of Ni–P bond distances ranging from 2.28–2.39 Å. In the fifth Ni1+ site, Ni1+ is bonded to four P3- atoms to form NiP4 tetrahedra that share corners with eleven NiP4 tetrahedra, corners with two equivalent NdP5 trigonal bipyramids, edges with two equivalent NdP6 pentagonal pyramids, and edges with three equivalent NdP5 trigonal bipyramids. There are a spread of Ni–P bond distances ranging from 2.32–2.46 Å. In the sixth Ni1+ site, Ni1+ is bonded to four P3- atoms to form NiP4 tetrahedra that share corners with four equivalent NdP6 pentagonal pyramids, corners with eight NiP4 tetrahedra, a cornercorner with one NdP5 trigonal bipyramid, an edgeedge with one NdP6 pentagonal pyramid, edges with two equivalent NiP4 tetrahedra, and edges with two equivalent NdP5 trigonal bipyramids. There are a spread of Ni–P bond distances ranging from 2.25–2.41 Å. In the seventh Ni1+ site, Ni1+ is bonded to four P3- atoms to form NiP4 tetrahedra that share corners with two equivalent NdP6 pentagonal pyramids, corners with six NiP4 tetrahedra, corners with two equivalent NdP5 trigonal bipyramids, edges with three equivalent NdP6 pentagonal pyramids, edges with four NiP4 tetrahedra, and an edgeedge with one NdP5 trigonal bipyramid. There are a spread of Ni–P bond distances ranging from 2.29–2.40 Å. There are four inequivalent P3- sites. In the first P3- site, P3- is bonded in a 9-coordinate geometry to two equivalent Nd+2.50+ and seven Ni1+ atoms. In the second P3- site, P3- is bonded in a 9-coordinate geometry to four Nd+2.50+ and five Ni1+ atoms. In the third P3- site, P3- is bonded in a 9-coordinate geometry to two equivalent Nd+2.50+ and seven Ni1+ atoms. In the fourth P3- site, P3- is bonded in a 9-coordinate geometry to three equivalent Nd+2.50+ and six Ni1+ atoms.

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2020-07-23. Materials Data on Nd2Ni7P4 by Materials Project. https://doi.org/10.17188/1264894

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