Materials Data on Cs2Si2Se5 by Materials Project
Cs2Si2Se5 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.66–4.22 Å. In the second Cs1+ site, Cs1+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.67–4.33 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four Se2- atoms to form corner-sharing SiSe4 tetrahedra. There are a spread of Si–Se bond distances ranging from 2.21–2.33 Å. In the second Si4+ site, Si4+ is bonded to four Se2- atoms to form corner-sharing SiSe4 tetrahedra. There are a spread of Si–Se bond distances ranging from 2.20–2.34 Å. There are six inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 1-coordinate geometry to three Cs1+ and one Si4+ atom. In the second Se2- site, Se2- is bonded in a 1-coordinate geometry to five Cs1+ and one Si4+ atom. In the third Se2- site, Se2- is bonded in a distorted water-like geometry to two Cs1+ and two Si4+ atoms. In the fourth Se2- site, Se2- is bonded in a distorted water-like geometry to three Cs1+ and two Si4+ atoms. In the fifth Se2- site, Se2- is bonded in a distorted water-like geometry to two equivalent Cs1+ and two equivalent Si4+ atoms. In the sixth Se2- site, Se2- is bonded in a distorted water-like geometry to four equivalent Cs1+ and two equivalent Si4+ atoms.