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DOE OSTI · 1719444

Materials Data on Hf(TlSe)4 by Materials Project

Abstract

Hf(TlSe)4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are three inequivalent Hf4+ sites. In the first Hf4+ site, Hf4+ is bonded to six Se2- atoms to form HfSe6 octahedra that share corners with three TlSe5 square pyramids, edges with two HfSe6 octahedra, and edges with six TlSe5 square pyramids. There are a spread of Hf–Se bond distances ranging from 2.66–2.78 Å. In the second Hf4+ site, Hf4+ is bonded to six Se2- atoms to form HfSe6 octahedra that share corners with four TlSe5 square pyramids, edges with two HfSe6 octahedra, and edges with four TlSe5 square pyramids. There are a spread of Hf–Se bond distances ranging from 2.65–2.79 Å. In the third Hf4+ site, Hf4+ is bonded to six Se2- atoms to form HfSe6 octahedra that share corners with two equivalent TlSe5 square pyramids, edges with two equivalent HfSe6 octahedra, and edges with four TlSe5 square pyramids. There are a spread of Hf–Se bond distances ranging from 2.70–2.74 Å. There are ten inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded to five Se2- atoms to form distorted TlSe5 square pyramids that share corners with two equivalent HfSe6 octahedra, corners with two equivalent TlSe5 square pyramids, edges with three HfSe6 octahedra, and an edgeedge with one TlSe5 square pyramid. The corner-sharing octahedra tilt angles range from 15–18°. There are a spread of Tl–Se bond distances ranging from 3.02–3.49 Å. In the second Tl1+ site, Tl1+ is bonded to five Se2- atoms to form distorted TlSe5 square pyramids that share corners with two HfSe6 octahedra, corners with two equivalent TlSe5 square pyramids, edges with three HfSe6 octahedra, and edges with three TlSe5 square pyramids. The corner-sharing octahedra tilt angles range from 7–9°. There are a spread of Tl–Se bond distances ranging from 3.08–3.48 Å. In the third Tl1+ site, Tl1+ is bonded in a distorted rectangular see-saw-like geometry to four Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.01–3.34 Å. In the fourth Tl1+ site, Tl1+ is bonded to five Se2- atoms to form distorted TlSe5 square pyramids that share corners with two HfSe6 octahedra, corners with two equivalent TlSe5 square pyramids, edges with three HfSe6 octahedra, and edges with two TlSe5 square pyramids. The corner-sharing octahedra tilt angles range from 10–11°. There are a spread of Tl–Se bond distances ranging from 3.05–3.53 Å. In the fifth Tl1+ site, Tl1+ is bonded in a distorted rectangular see-saw-like geometry to four Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.04–3.46 Å. In the sixth Tl1+ site, Tl1+ is bonded in a distorted rectangular see-saw-like geometry to four Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.02–3.51 Å. In the seventh Tl1+ site, Tl1+ is bonded to five Se2- atoms to form distorted TlSe5 square pyramids that share corners with two HfSe6 octahedra, corners with two equivalent TlSe5 square pyramids, edges with three HfSe6 octahedra, and edges with three TlSe5 square pyramids. The corner-sharing octahedra tilt angles range from 11–15°. There are a spread of Tl–Se bond distances ranging from 3.03–3.45 Å. In the eighth Tl1+ site, Tl1+ is bonded in a distorted rectangular see-saw-like geometry to four Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.00–3.36 Å. In the ninth Tl1+ site, Tl1+ is bonded in a distorted rectangular see-saw-like geometry to four Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.01–3.50 Å. In the tenth Tl1+ site, Tl1+ is bonded in a 5-coordinate geometry to five Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.05–3.50 Å. There are ten inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 6-coordinate geometry to one Hf4+ and five Tl1+ atoms. In the second Se2- site, Se2- is bonded to two equivalent Hf4+ and four Tl1+ atoms to form a mixture of distorted edge and corner-sharing SeHf2Tl4 octahedra. The corner-sharing octahedra tilt angles range from 12–20°. In the third Se2- site, Se2- is bonded in a 6-coordinate geometry to two Hf4+ and four Tl1+ atoms. In the fourth Se2- site, Se2- is bonded to two Hf4+ and four Tl1+ atoms to form a mixture of distorted edge and corner-sharing SeHf2Tl4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fifth Se2- site, Se2- is bonded in a 6-coordinate geometry to one Hf4+ and five Tl1+ atoms. In the sixth Se2- site, Se2- is bonded to two Hf4+ and four Tl1+ atoms to form a mixture of distorted edge and corner-sharing SeHf2Tl4 octahedra. The corner-sharing octahedral tilt angles are 12°. In the seventh Se2- site, Se2- is bonded in a 6-coordinate geometry to one Hf4+ and five Tl1+ atoms. In the eighth Se2- site, Se2- is bonded in a 6-coordinate geometry to one Hf4+ and five Tl1+ atoms. In the ninth Se2- site, Se2- is bonded to one Hf4+ and five Tl1+ atoms to form a mixture of distorted edge and corner-sharing SeHfTl5 octahedra. The corner-sharing octahedra tilt angles range from 0–20°. In the tenth Se2- site, Se2- is bonded in a 6-coordinate geometry to two Hf4+ and four Tl1+ atoms.

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2020-04-29. Materials Data on Hf(TlSe)4 by Materials Project. https://doi.org/10.17188/1719444

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