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DOE OSTI · 1745602

Materials Data on SrCa3(PbO4)2 by Materials Project

Abstract

SrCa3(PbO4)2 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. Sr2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Sr–O bond distances ranging from 2.46–2.92 Å. There are three inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.40–2.79 Å. In the second Ca2+ site, Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.54 Å. In the third Ca2+ site, Ca2+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Ca–O bond distances ranging from 2.39–2.80 Å. There are two inequivalent Pb4+ sites. In the first Pb4+ site, Pb4+ is bonded to six O2- atoms to form edge-sharing PbO6 octahedra. There are a spread of Pb–O bond distances ranging from 2.15–2.30 Å. In the second Pb4+ site, Pb4+ is bonded to six O2- atoms to form edge-sharing PbO6 octahedra. There are a spread of Pb–O bond distances ranging from 2.17–2.29 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to one Sr2+, two Ca2+, and two equivalent Pb4+ atoms to form distorted OSrCa2Pb2 trigonal bipyramids that share corners with two equivalent OCa4Pb square pyramids, corners with eight OSrCa2Pb2 trigonal bipyramids, a cornercorner with one OSrCaPb2 trigonal pyramid, edges with two equivalent OCa4Pb square pyramids, and edges with six OSr2Ca2Pb trigonal bipyramids. In the second O2- site, O2- is bonded to three Ca2+ and two equivalent Pb4+ atoms to form distorted OCa3Pb2 trigonal bipyramids that share corners with two equivalent OCa4Pb square pyramids, corners with eight OSrCa2Pb2 trigonal bipyramids, a cornercorner with one OSrCaPb2 trigonal pyramid, edges with four OCa4Pb square pyramids, and edges with four OSr2Ca2Pb trigonal bipyramids. In the third O2- site, O2- is bonded to one Sr2+, one Ca2+, and two equivalent Pb4+ atoms to form distorted OSrCaPb2 trigonal pyramids that share corners with two equivalent OCa4Pb square pyramids, corners with ten OSrCa2Pb2 trigonal bipyramids, corners with two equivalent OSrCaPb2 trigonal pyramids, edges with two equivalent OCa4Pb square pyramids, and edges with two equivalent OSrCa2Pb2 trigonal bipyramids. In the fourth O2- site, O2- is bonded to one Sr2+, two Ca2+, and two equivalent Pb4+ atoms to form distorted OSrCa2Pb2 trigonal bipyramids that share corners with two equivalent OCa4Pb square pyramids, corners with eight OSrCa2Pb2 trigonal bipyramids, corners with two equivalent OSrCaPb2 trigonal pyramids, edges with four OCa4Pb square pyramids, edges with two equivalent OSr2Ca2Pb trigonal bipyramids, and edges with two equivalent OSrCaPb2 trigonal pyramids. In the fifth O2- site, O2- is bonded to two equivalent Sr2+, two equivalent Ca2+, and one Pb4+ atom to form distorted OSr2Ca2Pb trigonal bipyramids that share a cornercorner with one OCa4Pb square pyramid, corners with six OSr2Ca2Pb trigonal bipyramids, corners with four equivalent OSrCaPb2 trigonal pyramids, and edges with eight OSrCa2Pb2 trigonal bipyramids. In the sixth O2- site, O2- is bonded to four Ca2+ and one Pb4+ atom to form distorted OCa4Pb square pyramids that share corners with four equivalent OCa4Pb square pyramids, corners with five OSrCa2Pb2 trigonal bipyramids, edges with four OCa4Pb square pyramids, edges with four OCa3Pb2 trigonal bipyramids, and edges with two equivalent OSrCaPb2 trigonal pyramids. In the seventh O2- site, O2- is bonded to two equivalent Sr2+, two equivalent Ca2+, and one Pb4+ atom to form distorted OSr2Ca2Pb trigonal bipyramids that share a cornercorner with one OCa4Pb square pyramid, corners with eight OSrCa2Pb2 trigonal bipyramids, corners with two equivalent OSrCaPb2 trigonal pyramids, and edges with eight OSr2Ca2Pb trigonal bipyramids. In the eighth O2- site, O2- is bonded to four Ca2+ and one Pb4+ atom to form distorted OCa4Pb square pyramids that share corners with four equivalent OCa4Pb square pyramids, corners with three OSr2Ca2Pb trigonal bipyramids, corners with two equivalent OSrCaPb2 trigonal pyramids, edges with four OCa4Pb square pyramids, and edges with six OSrCa2Pb2 trigonal bipyramids.

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2020-05-02. Materials Data on SrCa3(PbO4)2 by Materials Project. https://doi.org/10.17188/1745602

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