Materials Data on Rb2Zr2O5 by Materials Project

Abstract

Rb2Zr2O5 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded to eight equivalent O2- atoms to form distorted RbO8 hexagonal bipyramids that share corners with eight equivalent RbO12 cuboctahedra, edges with four equivalent RbO8 hexagonal bipyramids, edges with eight equivalent ZrO5 square pyramids, and faces with two equivalent RbO12 cuboctahedra. All Rb–O bond lengths are 2.96 Å. In the second Rb1+ site, Rb1+ is bonded to twelve O2- atoms to form RbO12 cuboctahedra that share corners with four equivalent RbO12 cuboctahedra, corners with eight equivalent RbO8 hexagonal bipyramids, faces with four equivalent RbO12 cuboctahedra, faces with two equivalent RbO8 hexagonal bipyramids, and faces with eight equivalent ZrO5 square pyramids. There are four shorter (2.91 Å) and eight longer (3.21 Å) Rb–O bond lengths. Zr4+ is bonded to five O2- atoms to form distorted ZrO5 square pyramids that share corners with five equivalent ZrO5 square pyramids, edges with four equivalent RbO8 hexagonal bipyramids, and faces with four equivalent RbO12 cuboctahedra. There are one shorter (2.05 Å) and four longer (2.10 Å) Zr–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four Rb1+ and two equivalent Zr4+ atoms. In the second O2- site, O2- is bonded to four equivalent Rb1+ and two equivalent Zr4+ atoms to form a mixture of distorted edge and corner-sharing ORb4Zr2 octahedra. The corner-sharing octahedral tilt angles are 0°.