Materials Data on CsAs2Se3 by Materials Project
CsAs2Se3 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Cs1+ sites. In the first Cs1+ site, Cs1+ is bonded in a 9-coordinate geometry to nine Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.80–4.27 Å. In the second Cs1+ site, Cs1+ is bonded in a distorted q6 geometry to nine Se2- atoms. There are a spread of Cs–Se bond distances ranging from 3.65–3.94 Å. There are three inequivalent As+2.50+ sites. In the first As+2.50+ site, As+2.50+ is bonded in a distorted L-shaped geometry to two Se2- atoms. There are one shorter (2.48 Å) and one longer (2.51 Å) As–Se bond lengths. In the second As+2.50+ site, As+2.50+ is bonded in a distorted rectangular see-saw-like geometry to three Se2- atoms. There are one shorter (2.38 Å) and two longer (2.47 Å) As–Se bond lengths. In the third As+2.50+ site, As+2.50+ is bonded in a distorted trigonal non-coplanar geometry to three Se2- atoms. There are one shorter (2.39 Å) and two longer (2.47 Å) As–Se bond lengths. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a distorted single-bond geometry to three equivalent Cs1+ and one As+2.50+ atom. In the second Se2- site, Se2- is bonded in a 1-coordinate geometry to three equivalent Cs1+ and one As+2.50+ atom. In the third Se2- site, Se2- is bonded in a 2-coordinate geometry to three Cs1+ and two As+2.50+ atoms. In the fourth Se2- site, Se2- is bonded in a 2-coordinate geometry to three Cs1+ and two As+2.50+ atoms.