Materials Data on CaH4SO6 by Materials Project
CaH4SO6 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of two CaH4SO6 sheets oriented in the (0, 1, 0) direction. Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.37–2.62 Å. There are two 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 0.98 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. S6+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.49 Å) and two longer (1.50 Å) S–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Ca2+ and one S6+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Ca2+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one Ca2+ and two H1+ atoms.