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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Yb2FeS4 by Materials Project

FeYb2S4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are sixteen inequivalent Yb+2.50+ sites. In the first Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form a mixture of corner and edge-sharing YbS6 octahedra. The corner-sharing octahedra tilt angles range from 2–6°. There are a spread of Yb–S bond distances ranging from 2.75–2.81 Å. In the second Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form a mixture of corner and edge-sharing YbS6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Yb–S bond distances ranging from 2.76–2.82 Å. In the third Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form edge-sharing YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.73–2.76 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 three equivalent YbS6 octahedra, corners with three FeS4 tetrahedra, an edgeedge with one FeS6 octahedra, and edges with five YbS6 octahedra. The corner-sharing octahedra tilt angles range from 2–5°. There are a spread of Yb–S bond distances ranging from 2.68–2.85 Å. In the fifth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with three FeS4 tetrahedra, an edgeedge with one FeS6 octahedra, and edges with six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.69–2.81 Å. In the sixth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with six FeS4 tetrahedra, edges with two equivalent FeS6 octahedra, and edges with four YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.73–2.82 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 FeS4 tetrahedra, edges with two FeS6 octahedra, and edges with four YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.73–2.81 Å. 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 FeS6 octahedra, corners with four FeS4 tetrahedra, and edges with six YbS6 octahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Yb–S bond distances ranging from 2.83–2.99 Å. In the ninth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with six FeS4 tetrahedra, edges with two FeS6 octahedra, and edges with four YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.73–2.81 Å. In the tenth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with four FeS4 tetrahedra, an edgeedge with one FeS6 octahedra, and edges with six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.66–2.83 Å. In the eleventh Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with six FeS4 tetrahedra, edges with two equivalent FeS6 octahedra, and edges with five YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.73–2.82 Å. In the twelfth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with four FeS4 tetrahedra, an edgeedge with one FeS6 octahedra, and edges with six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.66–2.83 Å. In the thirteenth 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 two equivalent FeS4 tetrahedra, and edges with seven YbS6 octahedra. The corner-sharing octahedra tilt angles range from 1–3°. There are a spread of Yb–S bond distances ranging from 2.70–2.97 Å. In the fourteenth 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 two equivalent FeS4 tetrahedra, and edges with seven YbS6 octahedra. The corner-sharing octahedra tilt angles range from 2–6°. There are a spread of Yb–S bond distances ranging from 2.69–2.84 Å. In the fifteenth 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 and edges with six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.67–2.81 Å. In the sixteenth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with two equivalent FeS4 tetrahedra and edges with eight YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.71–2.82 Å. There are eight inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four S2- atoms to form distorted FeS4 tetrahedra that share corners with nine YbS6 octahedra and a faceface with one FeS6 octahedra. The corner-sharing octahedra tilt angles range from 46–55°. There are a spread of Fe–S bond distances ranging from 2.14–2.23 Å. In the second Fe3+ site, Fe3+ is bonded to four S2- atoms to form distorted FeS4 tetrahedra that share corners with nine YbS6 octahedra and a faceface with one FeS6 octahedra. The corner-sharing octahedra tilt angles range from 44–56°. There are a spread of Fe–S bond distances ranging from 2.19–2.26 Å. In the third Fe3+ site, Fe3+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with ten YbS6 octahedra and a faceface with one FeS6 octahedra. The corner-sharing octahedra tilt angles range from 47–58°. There are a spread of Fe–S bond distances ranging from 2.19–2.31 Å. In the fourth Fe3+ site, Fe3+ is bonded to six S2- atoms to form FeS6 octahedra that share edges with six YbS6 octahedra and faces with two FeS4 tetrahedra. There are a spread of Fe–S bond distances ranging from 2.41–2.46 Å. In the fifth Fe3+ site, Fe3+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with eleven YbS6 octahedra and a faceface with one FeS6 octahedra. The corner-sharing octahedra tilt angles range from 47–61°. There are a spread of Fe–S bond distances ranging from 2.17–2.31 Å. In the sixth Fe3+ site, Fe3+ is bonded to six S2- atoms to form FeS6 octahedra that share corners with three equivalent YbS6 octahedra, edges with six YbS6 octahedra, and faces with two FeS4 tetrahedra. The corner-sharing octahedra tilt angles range from 2–4°. There are a spread of Fe–S bond distances ranging from 2.43–2.61 Å. In the seventh 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 48–59°. There are a spread of Fe–S bond distances ranging from 2.16–2.26 Å. In the eighth Fe3+ site, Fe3+ is bonded in a 3-coordinate geometry to six S2- atoms. There are a spread of Fe–S bond distances ranging from 2.19–2.99 Å. There are thirty-two inequivalent S2- sites. In the first S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Yb+2.50+ atoms. In the second S2- site, S2- is bonded in a rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. In the third S2- site, S2- is bonded in a distorted T-shaped geometry to three Yb+2.50+ atoms. In the fourth S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Yb+2.50+ atoms. In the fifth S2- site, S2- is bonded in a rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. 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 rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. In the eighth S2- site, S2- is bonded in a rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. 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 in a rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. In the eleventh S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twelfth S2- site, S2- is bonded in a rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. In the thirteenth S2- site, S2- is bonded to three Yb+2.50+ and two Fe3+ atoms to form a mixture of distorted corner and edge-sharing SYb3Fe2 square pyramids. In the fourteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the fifteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. In the sixteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. In the seventeenth S2- site, S2- is bonded in a 5-coordinate geometry to three Yb+2.50+ and two Fe3+ atoms. In the eighteenth S2- site, S2- is bonded to three Yb+2.50+ and two Fe3+ atoms to form a mixture of distorted corner and edge-sharing SYb3Fe2 square pyramids. In the nineteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twentieth S2- site, S2- is bonded in a rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. In the twenty-first S2- site, S2- is bonded to three Yb+2.50+ and two Fe3+ atoms to form a mixture of distorted corner and edge-sharing SYb3Fe2 square pyramids. In the twenty-second S2- site, S2- is bonded in a distorted T-shaped geometry to three Yb+2.50+ atoms. In the twenty-third S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twenty-fourth S2- site, S2- is bonded to three Yb+2.50+ and two Fe3+ atoms to form a mixture of distorted corner and edge-sharing SYb3Fe2 square pyramids. In the twenty-fifth S2- site, S2- is bonded to five Yb+2.50+ atoms to form edge-sharing SYb5 square pyramids. In the twenty-sixth S2- site, S2- is bonded to three Yb+2.50+ and two Fe3+ atoms to form distorted SYb3Fe2 square pyramids that share a cornercorner with one SYb5 square pyramid and edges with three SYb3Fe2 square pyramids. In the twenty-seventh S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twenty-eighth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twenty-ninth S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Yb+2.50+ atoms. In the thirtieth S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Yb+2.50+ atoms. In the thirty-first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the thirty-second S2- site, S2- is bonded to five Yb+2.50+ atoms to form SYb5 square pyramids that share corners with three SYb3Fe2 square pyramids and edges with two equivalent SYb5 square pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb2FeS4 by Materials Project

FeYb2S4 is Spinel structured and crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Yb+2.50+ is bonded to six equivalent S2- atoms to form YbS6 octahedra that share corners with six equivalent FeS4 tetrahedra and edges with six equivalent YbS6 octahedra. All Yb–S bond lengths are 2.80 Å. Fe3+ is bonded to four equivalent S2- atoms to form FeS4 tetrahedra that share corners with twelve equivalent YbS6 octahedra. The corner-sharing octahedral tilt angles are 53°. All Fe–S bond lengths are 2.24 Å. S2- is bonded in a rectangular see-saw-like geometry to three equivalent Yb+2.50+ and one Fe3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb2FeS4 by Materials Project

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.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Yb2FeS4 by Materials Project

FeYb2S4 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are twelve 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 three equivalent YbS6 octahedra, corners with six FeS4 tetrahedra, and edges with five YbS6 octahedra. The corner-sharing octahedra tilt angles range from 10–13°. There are a spread of Yb–S bond distances ranging from 2.82–2.86 Å. In the second 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 six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.71–2.89 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 three equivalent FeS4 tetrahedra, and edges with five YbS6 octahedra. The corner-sharing octahedra tilt angles range from 6–10°. There are a spread of Yb–S bond distances ranging from 2.64–2.81 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 five FeS4 tetrahedra and edges with six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.79–2.92 Å. 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 six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.80–3.00 Å. In the sixth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with five FeS4 tetrahedra and edges with six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.78–2.82 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 YbS6 octahedra, edges with four YbS6 octahedra, and a faceface with one FeS4 tetrahedra. The corner-sharing octahedra tilt angles range from 6–13°. There are a spread of Yb–S bond distances ranging from 2.62–2.86 Å. In the eighth 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 two shorter (2.81 Å) and four longer (2.82 Å) Yb–S bond lengths. In the ninth 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 2.78–2.84 Å. In the tenth Yb+2.50+ site, Yb+2.50+ is bonded to six S2- atoms to form YbS6 octahedra that share corners with five FeS4 tetrahedra and edges with six YbS6 octahedra. There are a spread of Yb–S bond distances ranging from 2.79–2.84 Å. In the eleventh 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 2.77–2.85 Å. In the twelfth 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 2.76–2.85 Å. There are six inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with ten YbS6 octahedra and a faceface with one YbS6 octahedra. The corner-sharing octahedra tilt angles range from 49–58°. There are a spread of Fe–S bond distances ranging from 2.19–2.37 Å. In the second Fe3+ site, Fe3+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with eleven YbS6 octahedra. The corner-sharing octahedra tilt angles range from 47–62°. There are a spread of Fe–S bond distances ranging from 2.20–2.28 Å. In the third 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 a spread of Fe–S bond distances ranging from 2.24–2.27 Å. In the fourth Fe3+ site, Fe3+ is bonded in a 6-coordinate geometry to six S2- atoms. There are a spread of Fe–S bond distances ranging from 2.28–2.84 Å. In the fifth 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 two shorter (2.26 Å) and two longer (2.27 Å) Fe–S bond lengths. In the sixth Fe3+ site, Fe3+ is bonded to four S2- atoms to form FeS4 tetrahedra that share corners with eleven YbS6 octahedra. The corner-sharing octahedra tilt angles range from 50–55°. There are one shorter (2.15 Å) and three longer (2.24 Å) Fe–S bond lengths. There are twenty-four 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 distorted rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the third S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to two Yb+2.50+ and two Fe3+ atoms. In the fourth S2- site, S2- is bonded to four Yb+2.50+ and one Fe3+ atom to form distorted corner-sharing SYb4Fe square pyramids. In the fifth S2- site, S2- is bonded to three Yb+2.50+ and two Fe3+ atoms to form distorted edge-sharing SYb3Fe2 square pyramids. In the sixth S2- site, S2- is bonded to four Yb+2.50+ and one Fe3+ atom to form SYb4Fe square pyramids that share corners with five SYb4Fe square pyramids and an edgeedge with one SYb3Fe2 square pyramid. In the seventh S2- site, S2- is bonded in a 3-coordinate geometry to two Yb+2.50+ and one Fe3+ atom. In the eighth S2- site, S2- is bonded in a T-shaped geometry to three Yb+2.50+ atoms. In the ninth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the tenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the eleventh S2- site, S2- is bonded to three Yb+2.50+ and two Fe3+ atoms to form distorted SYb3Fe2 square pyramids that share corners with two equivalent SYb4Fe square pyramids and edges with two equivalent SYb3Fe2 square pyramids. In the twelfth S2- site, S2- is bonded in a square co-planar geometry to three Yb+2.50+ and one Fe3+ atom. In the thirteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the fourteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the fifteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the sixteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the seventeenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the eighteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the nineteenth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twentieth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twenty-first S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twenty-second S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twenty-third S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom. In the twenty-fourth S2- site, S2- is bonded in a rectangular see-saw-like geometry to three Yb+2.50+ and one Fe3+ atom.

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