Materials Data on KSrAs(H4O3)4 by Materials Project
KSr(H2O)8AsO4 crystallizes in the tetragonal I4_1md space group. The structure is three-dimensional and consists of four AsO4 clusters and one KSr(H2O)8 framework. In each AsO4 cluster, As5+ is bonded in a tetrahedral geometry to four O2- atoms. All As–O bond lengths are 1.73 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one As5+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one As5+ atom. In the KSr(H2O)8 framework, K1+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of K–O bond distances ranging from 2.75–2.94 Å. Sr2+ is bonded in a 8-coordinate geometry to eight O2- atoms. All Sr–O bond lengths are 2.67 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a water-like geometry to one K1+, one Sr2+, and two H1+ atoms. In the second O2- site, O2- is bonded in a water-like geometry to one K1+, one Sr2+, and two equivalent H1+ atoms. In the third O2- site, O2- is bonded in a water-like geometry to one K1+, one Sr2+, and two equivalent H1+ atoms.