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DOE OSTI · 1723982

Materials Data on PbS by Materials Project

Abstract

PbS crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are three inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded to five S2- atoms to form distorted PbS5 square pyramids that share corners with four equivalent PbS6 pentagonal pyramids, corners with two equivalent PbS5 square pyramids, corners with four equivalent PbS4 tetrahedra, edges with two equivalent PbS6 pentagonal pyramids, edges with two equivalent PbS5 square pyramids, and a faceface with one PbS5 square pyramid. There are a spread of Pb–S bond distances ranging from 2.81–3.14 Å. In the second Pb2+ site, Pb2+ is bonded to four S2- atoms to form distorted PbS4 tetrahedra that share corners with eight equivalent PbS5 square pyramids, corners with two equivalent PbS4 tetrahedra, and edges with two equivalent PbS6 pentagonal pyramids. There are two shorter (2.81 Å) and two longer (2.89 Å) Pb–S bond lengths. In the third Pb2+ site, Pb2+ is bonded to six S2- atoms to form distorted PbS6 pentagonal pyramids that share corners with eight equivalent PbS5 square pyramids, edges with four equivalent PbS5 square pyramids, edges with two equivalent PbS4 tetrahedra, and faces with two equivalent PbS6 pentagonal pyramids. There are two shorter (2.91 Å) and four longer (3.13 Å) Pb–S bond lengths. There are three inequivalent S2- sites. In the first S2- site, S2- is bonded to five Pb2+ atoms to form distorted SPb5 trigonal bipyramids that share corners with four equivalent SPb6 pentagonal pyramids, corners with two equivalent SPb5 trigonal bipyramids, edges with two equivalent SPb6 pentagonal pyramids, edges with two equivalent SPb5 trigonal bipyramids, and a faceface with one SPb5 trigonal bipyramid. In the second S2- site, S2- is bonded in a 4-coordinate geometry to four Pb2+ atoms. In the third S2- site, S2- is bonded to six Pb2+ atoms to form distorted SPb6 pentagonal pyramids that share corners with eight equivalent SPb5 trigonal bipyramids, edges with four equivalent SPb5 trigonal bipyramids, and faces with two equivalent SPb6 pentagonal pyramids.

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2020-05-05. Materials Data on PbS by Materials Project. https://doi.org/10.17188/1723982

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36 MATERIALS SCIENCE↗