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DOE OSTI · 1675655

Materials Data on Yb4PbS8 by Materials Project

Abstract

Yb4PbS8 crystallizes in the monoclinic Pm space group. The structure is three-dimensional. there are eight inequivalent Yb3+ sites. In the first Yb3+ site, Yb3+ is bonded to eight S2- atoms to form distorted YbS8 hexagonal bipyramids that share corners with two equivalent YbS6 octahedra, edges with two equivalent YbS8 hexagonal bipyramids, and a faceface with one YbS6 octahedra. The corner-sharing octahedral tilt angles are 30°. There are a spread of Yb–S bond distances ranging from 2.58–3.22 Å. In the second Yb3+ site, Yb3+ is bonded in a 6-coordinate geometry to six S2- atoms. There are a spread of Yb–S bond distances ranging from 2.77–2.95 Å. In the third Yb3+ site, Yb3+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with two equivalent YbS8 hexagonal bipyramids, corners with two equivalent YbS6 octahedra, and a faceface with one YbS8 hexagonal bipyramid. The corner-sharing octahedral tilt angles are 65°. There are a spread of Yb–S bond distances ranging from 2.64–2.92 Å. In the fourth Yb3+ site, Yb3+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Yb–S bond distances ranging from 2.71–2.95 Å. In the fifth Yb3+ site, Yb3+ is bonded in a 6-coordinate geometry to six S2- atoms. There are a spread of Yb–S bond distances ranging from 2.78–2.99 Å. In the sixth Yb3+ site, Yb3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Yb–S bond distances ranging from 2.59–3.25 Å. In the seventh Yb3+ site, Yb3+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of Yb–S bond distances ranging from 2.71–2.94 Å. In the eighth Yb3+ site, Yb3+ is bonded to six S2- atoms to form distorted corner-sharing YbS6 octahedra. The corner-sharing octahedral tilt angles are 65°. There are a spread of Yb–S bond distances ranging from 2.63–2.96 Å. There are two inequivalent Pb4+ sites. In the first Pb4+ site, Pb4+ is bonded in a 4-coordinate geometry to four S2- atoms. There are a spread of Pb–S bond distances ranging from 2.46–3.28 Å. In the second Pb4+ site, Pb4+ is bonded in a 3-coordinate geometry to three S2- atoms. There are two shorter (2.46 Å) and one longer (2.88 Å) Pb–S bond lengths. There are sixteen inequivalent S2- sites. In the first S2- site, S2- is bonded in a 6-coordinate geometry to two Yb3+, two equivalent Pb4+, and two S2- atoms. There are one shorter (2.52 Å) and one longer (2.55 Å) S–S bond lengths. In the second S2- site, S2- is bonded in a 6-coordinate geometry to five Yb3+ and one Pb4+ atom. In the third S2- site, S2- is bonded in a 4-coordinate geometry to four Yb3+ and two S2- atoms. There are one shorter (2.43 Å) and one longer (2.52 Å) S–S bond lengths. In the fourth S2- site, S2- is bonded in a 3-coordinate geometry to three Yb3+, one Pb4+, and one S2- atom. In the fifth S2- site, S2- is bonded in a 4-coordinate geometry to two equivalent Yb3+ and two equivalent S2- atoms. Both S–S bond lengths are 2.51 Å. In the sixth S2- site, S2- is bonded in a 4-coordinate geometry to four Yb3+ and two S2- atoms. The S–S bond length is 2.54 Å. In the seventh S2- site, S2- is bonded in a 4-coordinate geometry to five Yb3+ and one S2- atom. In the eighth S2- site, S2- is bonded in a distorted linear geometry to two Yb3+ and four S2- atoms. Both S–S bond lengths are 2.51 Å. In the ninth S2- site, S2- is bonded in a 2-coordinate geometry to two Yb3+ and four S2- atoms. There are one shorter (2.42 Å) and one longer (2.56 Å) S–S bond lengths. In the tenth S2- site, S2- is bonded in a 3-coordinate geometry to three Yb3+ and one S2- atom. The S–S bond length is 2.52 Å. In the eleventh S2- site, S2- is bonded in a 4-coordinate geometry to four Yb3+ and two S2- atoms. The S–S bond length is 2.51 Å. In the twelfth S2- site, S2- is bonded in a 4-coordinate geometry to two equivalent Yb3+ and two equivalent S2- atoms. In the thirteenth S2- site, S2- is bonded in a 4-coordinate geometry to five Yb3+ and one S2- atom. The S–S bond length is 2.55 Å. In the fourteenth S2- site, S2- is bonded in a 3-coordinate geometry to four Yb3+ and two S2- atoms. In the fifteenth S2- site, S2- is bonded in a 6-coordinate geometry to five Yb3+ and one Pb4+ atom. In the sixteenth S2- site, S2- is bonded in a 6-coordinate geometry to two Yb3+, two equivalent Pb4+, and two S2- atoms.

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2018-07-12. Materials Data on Yb4PbS8 by Materials Project. https://doi.org/10.17188/1675655

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36 MATERIALS SCIENCE↗