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DOE OSTI · 1282912

Materials Data on Yb2FeS4 by Materials Project

Abstract

FeYb2S4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are eight inequivalent Yb+2.50+ sites. In the first Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with six FeS4 tetrahedra and edges with six YbS6 octahedra. There are four shorter (2.79 Å) and two longer (2.81 Å) Yb–S bond lengths. In the second Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with six FeS4 tetrahedra and edges with six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.79–2.81 Å. In the third Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with three equivalent YbS6 octahedra, corners with four FeS4 tetrahedra, and edges with six YbS6 octahedra. The corner-sharing octahedra tilt angles range from 11–16°. There are a spread of Yb–S bond distances ranging from 2.65–2.93 Å. In the fourth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with six FeS4 tetrahedra and edges with six YbS6 octahedra. There are three shorter (2.79 Å) and three longer (2.81 Å) Yb–S bond lengths. In the fifth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with four FeS4 tetrahedra and edges with seven YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.68–2.95 Å. In the sixth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form distorted YbS6 octahedra that share corners with six YbS6 octahedra, edges with two equivalent FeS6 octahedra, edges with four YbS6 octahedra, and a faceface with one FeS4 tetrahedra. The corner-sharing octahedra tilt angles range from 10–35°. There are a spread of Yb–S bond distances ranging from 2.62–2.89 Å. In the seventh Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with six equivalent YbS6 octahedra, corners with four equivalent FeS4 tetrahedra, edges with two equivalent YbS6 octahedra, and edges with four equivalent FeS6 octahedra. The corner-sharing octahedra tilt angles range from 10–35°. There are two shorter (2.70 Å) and four longer (2.83 Å) Yb–S bond lengths. In the eighth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with three equivalent FeS4 tetrahedra, edges with two equivalent FeS6 octahedra, and edges with six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.70–2.84 Å. There are four inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with twelve YbS6 octahedra. The corner-sharing octahedra tilt angles range from 51–54°. There are one shorter (2.20 Å) and three longer (2.24 Å) Fe–S bond lengths. In the second Fe3+ site, Fe3+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with twelve YbS6 octahedra. The corner-sharing octahedra tilt angles range from 52–53°. There are a spread of Fe–S bond distances ranging from 2.21–2.23 Å. In the third Fe3+ site, Fe3+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with four equivalent FeS6 octahedra, corners with eight YbS6 octahedra, and a faceface with one YbS6 octahedra. The corner-sharing octahedra tilt angles range from 46–66°. There are a spread of Fe–S bond distances ranging from 2.25–2.39 Å. In the fourth Fe3+ site, Fe3+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with four equivalent FeS4 tetrahedra, edges with two equivalent FeS6 octahedra, and edges with six YbS6 octahedra. There are a spread of Fe–S bond distances ranging from 2.30–2.64 Å. There are twelve inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the third S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the fourth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the fifth S2- site, S2- is bonded to four Yb+2.50+ and one Fe3+ atom to form distorted SYb4Fe square pyramids that share a cornercorner with one SYb2Fe2 tetrahedra and edges with two equivalent SYb3Fe2 square pyramids. In the sixth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the seventh S2- site, S2- is bonded in a distorted T-shaped geometry to three Yb+2.50+ atoms. In the eighth S2- site, S2- is bonded to three Yb+2.50+ and two Fe3+ atoms to form distorted SYb3Fe2 square pyramids that share corners with three equivalent SYb3Fe2 square pyramids, a cornercorner with one SYb2Fe2 tetrahedra, edges with three SYb4Fe square pyramids, and edges with two equivalent SYb2Fe2 tetrahedra. In the ninth S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Yb+2.50+ atoms. In the tenth S2- site, S2- is bonded to two Yb+2.50+ and two equivalent Fe3+ atoms to form distorted SYb2Fe2 tetrahedra that share corners with three SYb4Fe square pyramids, corners with three equivalent SYb2Fe2 tetrahedra, and edges with four equivalent SYb3Fe2 square pyramids. In the eleventh S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twelfth S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to one Yb+2.50+ and three Fe3+ atoms.

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2020-05-02. Materials Data on Yb2FeS4 by Materials Project. https://doi.org/10.17188/1282912

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