Materials Data on RbFeSe2O7 by Materials Project

Abstract

RbFe(SeO4)(SeO3) crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded to twelve O2- atoms to form RbO12 cuboctahedra that share edges with six equivalent RbO12 cuboctahedra, edges with six equivalent SeO4 tetrahedra, and faces with two equivalent FeO6 octahedra. There are six shorter (3.21 Å) and six longer (3.24 Å) Rb–O bond lengths. In the second Rb1+ site, Rb1+ is bonded to twelve equivalent O2- atoms to form RbO12 cuboctahedra that share edges with six equivalent RbO12 cuboctahedra and edges with six equivalent FeO6 octahedra. All Rb–O bond lengths are 3.27 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with three equivalent SeO4 tetrahedra, edges with three equivalent RbO12 cuboctahedra, and a faceface with one RbO12 cuboctahedra. There are three shorter (1.98 Å) and three longer (2.10 Å) Fe–O bond lengths. There are two inequivalent Se5+ sites. In the first Se5+ site, Se5+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with three equivalent FeO6 octahedra and edges with three equivalent RbO12 cuboctahedra. The corner-sharing octahedral tilt angles are 21°. There is one shorter (1.64 Å) and three longer (1.68 Å) Se–O bond length. In the second Se5+ site, Se5+ is bonded in a distorted trigonal non-coplanar geometry to three equivalent O2- atoms. All Se–O bond lengths are 1.74 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Rb1+, one Fe3+, and one Se5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to two equivalent Rb1+, one Fe3+, and one Se5+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to three equivalent Rb1+ and one Se5+ atom.