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DOE OSTI · 1264872

Materials Data on Pb5(IF4)2 by Materials Project

Abstract

Pb5(IF4)2 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are five inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 4-coordinate geometry to three equivalent I1- and seven F1- atoms. All Pb–I bond lengths are 3.78 Å. There are a spread of Pb–F bond distances ranging from 2.42–2.77 Å. In the second Pb2+ site, Pb2+ is bonded in a 3-coordinate geometry to three equivalent I1- and seven F1- atoms. All Pb–I bond lengths are 3.35 Å. There are a spread of Pb–F bond distances ranging from 2.55–3.03 Å. In the third Pb2+ site, Pb2+ is bonded in a 7-coordinate geometry to three equivalent I1- and seven F1- atoms. All Pb–I bond lengths are 3.87 Å. There are a spread of Pb–F bond distances ranging from 2.44–2.73 Å. In the fourth Pb2+ site, Pb2+ is bonded in a 8-coordinate geometry to eight F1- atoms. There are a spread of Pb–F bond distances ranging from 2.55–2.82 Å. In the fifth Pb2+ site, Pb2+ is bonded in a 4-coordinate geometry to three equivalent I1- and four F1- atoms. All Pb–I bond lengths are 3.33 Å. There are one shorter (2.34 Å) and three longer (2.59 Å) Pb–F bond lengths. There are two inequivalent I1- sites. In the first I1- site, I1- is bonded in a 9-coordinate geometry to six Pb2+ and three equivalent F1- atoms. All I–F bond lengths are 3.67 Å. In the second I1- site, I1- is bonded in a 12-coordinate geometry to six Pb2+ and six F1- atoms. All I–F bond lengths are 3.81 Å. There are eight inequivalent F1- sites. In the first F1- site, F1- is bonded to four Pb2+ atoms to form distorted FPb4 trigonal pyramids that share corners with four FPb4I3 tetrahedra, corners with six equivalent FPb4 trigonal pyramids, and edges with three equivalent FPb4 trigonal pyramids. In the second F1- site, F1- is bonded to four Pb2+ and three equivalent I1- atoms to form distorted FPb4I3 tetrahedra that share corners with ten FPb4 trigonal pyramids, edges with nine FPb4I3 tetrahedra, and a faceface with one FPb4I3 trigonal pyramid. In the third F1- site, F1- is bonded to four Pb2+ and three equivalent I1- atoms to form a mixture of distorted face, edge, and corner-sharing FPb4I3 trigonal pyramids. In the fourth F1- site, F1- is bonded to four Pb2+ atoms to form distorted FPb4 trigonal pyramids that share corners with six FPb4I3 tetrahedra, corners with six equivalent FPb4 trigonal pyramids, edges with three equivalent FPb4 tetrahedra, and edges with three equivalent FPb4 trigonal pyramids. In the fifth F1- site, F1- is bonded to four Pb2+ atoms to form distorted FPb4 tetrahedra that share corners with six equivalent FPb4 tetrahedra, corners with six FPb4 trigonal pyramids, edges with three equivalent FPb4I3 tetrahedra, and edges with three equivalent FPb4 trigonal pyramids. In the sixth F1- site, F1- is bonded to four Pb2+ and three equivalent I1- atoms to form distorted edge-sharing FPb4I3 tetrahedra. In the seventh F1- site, F1- is bonded in a 6-coordinate geometry to six Pb2+ atoms. In the eighth F1- site, F1- is bonded in a 3-coordinate geometry to three equivalent Pb2+ atoms.

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2020-07-15. Materials Data on Pb5(IF4)2 by Materials Project. https://doi.org/10.17188/1264872

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36 MATERIALS SCIENCE↗