Materials Data on HfTl2Se3 by Materials Project
Tl2HfSe3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Hf4+ is bonded to six Se2- atoms to form HfSe6 octahedra that share corners with three equivalent TlSe6 octahedra, edges with three equivalent TlSe6 octahedra, and edges with four equivalent HfSe6 octahedra. The corner-sharing octahedra tilt angles range from 1–14°. There are a spread of Hf–Se bond distances ranging from 2.58–2.82 Å. There are two inequivalent Tl1+ sites. In the first Tl1+ site, Tl1+ is bonded in a 6-coordinate geometry to six Se2- atoms. There are a spread of Tl–Se bond distances ranging from 3.13–3.55 Å. In the second Tl1+ site, Tl1+ is bonded to six Se2- atoms to form distorted TlSe6 octahedra that share corners with three equivalent HfSe6 octahedra, edges with three equivalent HfSe6 octahedra, and edges with six equivalent TlSe6 octahedra. The corner-sharing octahedra tilt angles range from 1–14°. There are a spread of Tl–Se bond distances ranging from 3.12–3.61 Å. There are three 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 in a 6-coordinate geometry to two equivalent Hf4+ and four Tl1+ atoms. In the third Se2- site, Se2- is bonded in a 6-coordinate geometry to three equivalent Hf4+ and three equivalent Tl1+ atoms.