Materials Data on Cs3As5O9 by Materials Project
Cs3As5O9 crystallizes in the trigonal P31m space group. The structure is three-dimensional. Cs1+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Cs–O bond distances ranging from 3.07–3.48 Å. There are two inequivalent As3+ sites. In the first As3+ site, As3+ is bonded in a distorted T-shaped geometry to three equivalent O2- atoms. All As–O bond lengths are 1.82 Å. In the second As3+ site, As3+ is bonded in a trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.71 Å) and two longer (1.90 Å) As–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Cs1+ and two As3+ atoms. In the second O2- site, O2- is bonded in a 1-coordinate geometry to three equivalent Cs1+ and one As3+ atom.