Materials Data on CaSO4 by Materials Project

Abstract

CaSO4 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ca2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.58 Å. S6+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of S–O bond distances ranging from 1.47–1.50 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees 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 1-coordinate geometry to one Ca2+ and one S6+ atom.