Materials Data on RbCr(SO4)2 by Materials Project

Abstract

RbCr(SO4)2 crystallizes in the trigonal P-3c1 space group. The structure is three-dimensional. Rb1+ is bonded to six equivalent O2- atoms to form distorted RbO6 cuboctahedra that share corners with six equivalent SO4 tetrahedra and edges with six equivalent RbO6 cuboctahedra. All Rb–O bond lengths are 3.05 Å. Cr3+ is bonded to six equivalent O2- atoms to form CrO6 octahedra that share corners with six equivalent SO4 tetrahedra. All Cr–O bond lengths are 2.01 Å. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with three equivalent RbO6 cuboctahedra and corners with three equivalent CrO6 octahedra. The corner-sharing octahedral tilt angles are 40°. There is one shorter (1.46 Å) and three longer (1.50 Å) S–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Cr3+ and one S6+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent Rb1+ and one S6+ atom.