Materials Data on Cs2SnAs2Se9 by Materials Project
Cs2SnAs2Se9 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 11-coordinate geometry to eleven Se+1.33- atoms. There are a spread of Cs–Se bond distances ranging from 3.71–4.27 Å. In the second Cs1+ site, Cs1+ is bonded in a 11-coordinate geometry to eleven Se+1.33- atoms. There are a spread of Cs–Se bond distances ranging from 3.79–4.24 Å. Sn2+ is bonded in an octahedral geometry to six Se+1.33- atoms. There are a spread of Sn–Se bond distances ranging from 2.72–2.83 Å. There are two inequivalent As4+ sites. In the first As4+ site, As4+ is bonded in a distorted trigonal non-coplanar geometry to three Se+1.33- atoms. There are a spread of As–Se bond distances ranging from 2.37–2.53 Å. In the second As4+ site, As4+ is bonded in a trigonal non-coplanar geometry to three Se+1.33- atoms. There are a spread of As–Se bond distances ranging from 2.36–2.47 Å. There are nine inequivalent Se+1.33- sites. In the first Se+1.33- site, Se+1.33- is bonded in a 4-coordinate geometry to two Cs1+, one Sn2+, and one Se+1.33- atom. The Se–Se bond length is 2.38 Å. In the second Se+1.33- site, Se+1.33- is bonded in a 2-coordinate geometry to three Cs1+, one Sn2+, and one As4+ atom. In the third Se+1.33- site, Se+1.33- is bonded in a 1-coordinate geometry to three Cs1+, one Sn2+, and one Se+1.33- atom. The Se–Se bond length is 2.38 Å. In the fourth Se+1.33- site, Se+1.33- is bonded in a distorted L-shaped geometry to two equivalent Cs1+, one Sn2+, and one As4+ atom. In the fifth Se+1.33- site, Se+1.33- is bonded in a 1-coordinate geometry to three Cs1+, one As4+, and one Se+1.33- atom. The Se–Se bond length is 2.35 Å. In the sixth Se+1.33- site, Se+1.33- is bonded in a 1-coordinate geometry to one Cs1+, one As4+, and one Se+1.33- atom. In the seventh Se+1.33- site, Se+1.33- is bonded in a 1-coordinate geometry to three Cs1+, one Sn2+, and one Se+1.33- atom. In the eighth Se+1.33- site, Se+1.33- is bonded in a distorted water-like geometry to two equivalent Cs1+, one Sn2+, and one As4+ atom. In the ninth Se+1.33- site, Se+1.33- is bonded in a 1-coordinate geometry to three Cs1+, one As4+, and one Se+1.33- atom.