Materials Data on CaH2S2N2O9 by Materials Project

Abstract

CaH2S2O9N2 crystallizes in the monoclinic P2_1/m space group. The structure is two-dimensional and consists of four ammonia molecules and one CaH2S2O9 sheet oriented in the (0, 0, 1) direction. In the CaH2S2O9 sheet, Ca2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.74 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are two inequivalent S2+ sites. In the first S2+ site, S2+ is bonded in a tetrahedral geometry to four O2- atoms. There is three shorter (1.48 Å) and one longer (1.51 Å) S–O bond length. In the second S2+ site, S2+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of S–O bond distances ranging from 1.48–1.50 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Ca2+ and one S2+ atom. In the second O2- site, O2- is bonded in a distorted water-like geometry to one Ca2+ and two equivalent H1+ atoms. In the third O2- site, O2- is bonded in a single-bond geometry to one S2+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one S2+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to one Ca2+ and one S2+ atom. In the sixth O2- site, O2- is bonded in a distorted water-like geometry to one Ca2+ and one S2+ atom. In the seventh O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ca2+ and one S2+ atom.