Materials Data on CsTaGeS5 by Materials Project
CsTaGeS5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Cs1+ is bonded in a 10-coordinate geometry to ten S2- atoms. There are a spread of Cs–S bond distances ranging from 3.58–4.16 Å. Ta5+ is bonded to six S2- atoms to form TaS6 octahedra that share corners with two equivalent GeS4 tetrahedra and edges with two equivalent TaS6 octahedra. There are a spread of Ta–S bond distances ranging from 2.34–2.57 Å. Ge4+ is bonded to four S2- atoms to form GeS4 tetrahedra that share corners with two equivalent TaS6 octahedra and an edgeedge with one GeS4 tetrahedra. The corner-sharing octahedra tilt angles range from 71–74°. There are a spread of Ge–S bond distances ranging from 2.21–2.29 Å. There are five inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted L-shaped geometry to one Cs1+ and two equivalent Ta5+ atoms. In the second S2- site, S2- is bonded in a 2-coordinate geometry to two equivalent Cs1+ and two equivalent Ta5+ atoms. In the third S2- site, S2- is bonded in a distorted water-like geometry to three equivalent Cs1+, one Ta5+, and one Ge4+ atom. In the fourth S2- site, S2- is bonded in a distorted water-like geometry to two equivalent Cs1+, one Ta5+, and one Ge4+ atom. In the fifth S2- site, S2- is bonded in a 2-coordinate geometry to two equivalent Cs1+ and two equivalent Ge4+ atoms.