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DOE OSTI · 1709537

Materials Data on Sr3Nd4O9 by Materials Project

Abstract

Sr3Nd4O9 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Sr–O bond distances ranging from 2.42–2.62 Å. In the second Sr2+ site, Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.52–2.80 Å. In the third Sr2+ site, Sr2+ is bonded to seven O2- atoms to form distorted SrO7 pentagonal bipyramids that share corners with three equivalent NdO7 pentagonal bipyramids, a cornercorner with one NdO6 pentagonal pyramid, an edgeedge with one NdO7 pentagonal bipyramid, and edges with four NdO6 pentagonal pyramids. There are a spread of Sr–O bond distances ranging from 2.50–2.87 Å. There are four inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded to six O2- atoms to form distorted NdO6 pentagonal pyramids that share a cornercorner with one NdO6 pentagonal pyramid, edges with two equivalent SrO7 pentagonal bipyramids, edges with two equivalent NdO7 pentagonal bipyramids, and edges with two equivalent NdO6 pentagonal pyramids. There are a spread of Nd–O bond distances ranging from 2.32–2.50 Å. In the second Nd3+ site, Nd3+ is bonded to six O2- atoms to form distorted NdO6 pentagonal pyramids that share a cornercorner with one SrO7 pentagonal bipyramid, corners with two equivalent NdO7 pentagonal bipyramids, a cornercorner with one NdO6 pentagonal pyramid, an edgeedge with one NdO7 pentagonal bipyramid, edges with two equivalent SrO7 pentagonal bipyramids, and edges with two equivalent NdO6 pentagonal pyramids. There are a spread of Nd–O bond distances ranging from 2.32–2.57 Å. In the third Nd3+ site, Nd3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Nd–O bond distances ranging from 2.38–2.66 Å. In the fourth Nd3+ site, Nd3+ is bonded to seven O2- atoms to form distorted NdO7 pentagonal bipyramids that share corners with three equivalent SrO7 pentagonal bipyramids, corners with two equivalent NdO6 pentagonal pyramids, an edgeedge with one SrO7 pentagonal bipyramid, and edges with three NdO6 pentagonal pyramids. There are a spread of Nd–O bond distances ranging from 2.35–2.81 Å. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded to two Sr2+ and two Nd3+ atoms to form distorted OSr2Nd2 trigonal pyramids that share corners with two OSr2Nd4 octahedra, corners with six OSr2Nd3 trigonal bipyramids, edges with two OSr2Nd4 octahedra, and edges with three OSr2Nd3 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 48–49°. In the second O2- site, O2- is bonded to two Sr2+ and three Nd3+ atoms to form distorted OSr2Nd3 trigonal bipyramids that share corners with four OSr2Nd4 octahedra, corners with five OSr3Nd2 trigonal bipyramids, a cornercorner with one OSr2Nd2 trigonal pyramid, edges with two OSr2Nd4 octahedra, edges with three OSr3Nd2 trigonal bipyramids, and an edgeedge with one OSr2Nd2 trigonal pyramid. The corner-sharing octahedra tilt angles range from 38–71°. In the third O2- site, O2- is bonded to three Sr2+ and two Nd3+ atoms to form distorted OSr3Nd2 trigonal bipyramids that share corners with four OSr2Nd4 octahedra, corners with four OSr2Nd3 trigonal bipyramids, corners with two equivalent OSr2Nd2 trigonal pyramids, edges with two OSr2Nd4 octahedra, edges with three OSr2Nd3 trigonal bipyramids, and an edgeedge with one OSr2Nd2 trigonal pyramid. The corner-sharing octahedra tilt angles range from 45–62°. In the fourth O2- site, O2- is bonded to one Sr2+ and four Nd3+ atoms to form distorted OSrNd4 trigonal bipyramids that share corners with four OSr2Nd4 octahedra, corners with four OSr2Nd3 trigonal bipyramids, corners with two equivalent OSr2Nd2 trigonal pyramids, an edgeedge with one OSr3Nd3 octahedra, edges with three OSr2Nd3 trigonal bipyramids, and a faceface with one OSr2Nd4 octahedra. The corner-sharing octahedra tilt angles range from 28–53°. In the fifth O2- site, O2- is bonded to two Sr2+ and four Nd3+ atoms to form OSr2Nd4 octahedra that share corners with two equivalent OSr3Nd3 octahedra, corners with eight OSr2Nd3 trigonal bipyramids, a cornercorner with one OSr2Nd2 trigonal pyramid, edges with three OSr2Nd3 trigonal bipyramids, an edgeedge with one OSr2Nd2 trigonal pyramid, a faceface with one OSr3Nd3 octahedra, and a faceface with one OSrNd4 trigonal bipyramid. The corner-sharing octahedra tilt angles range from 32–34°. In the sixth O2- site, O2- is bonded to two Sr2+ and three Nd3+ atoms to form distorted OSr2Nd3 trigonal bipyramids that share corners with four OSr2Nd4 octahedra, corners with three OSr2Nd3 trigonal bipyramids, a cornercorner with one OSr2Nd2 trigonal pyramid, edges with two OSr2Nd4 octahedra, edges with three OSr2Nd3 trigonal bipyramids, and an edgeedge with one OSr2Nd2 trigonal pyramid. The corner-sharing octahedra tilt angles range from 37–67°. In the seventh O2- site, O2- is bonded to three Sr2+ and three Nd3+ atoms to form OSr3Nd3 octahedra that share corners with two equivalent OSr2Nd4 octahedra, corners with eight OSr2Nd3 trigonal bipyramids, a cornercorner with one OSr2Nd2 trigonal pyramid, edges with four OSr2Nd3 trigonal bipyramids, an edgeedge with one OSr2Nd2 trigonal pyramid, and a faceface with one OSr2Nd4 octahedra. The corner-sharing octahedra tilt angles range from 32–34°. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to three Sr2+ and two Nd3+ atoms. In the ninth O2- site, O2- is bonded in a 5-coordinate geometry to two Sr2+ and three Nd3+ atoms.

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2020-05-02. Materials Data on Sr3Nd4O9 by Materials Project. https://doi.org/10.17188/1709537

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