Materials Data on KSr(BiO3)2 by Materials Project

Abstract

KSr(BiO3)2 crystallizes in the tetragonal I-42m space group. The structure is three-dimensional. K is bonded to eight O atoms to form distorted KO8 cuboctahedra that share corners with four equivalent KO8 cuboctahedra and edges with eight equivalent BiO6 octahedra. There are four shorter (2.83 Å) and four longer (3.00 Å) K–O bond lengths. Sr is bonded in a 8-coordinate geometry to eight O atoms. There are four shorter (2.59 Å) and four longer (3.00 Å) Sr–O bond lengths. Bi is bonded to six O atoms to form BiO6 octahedra that share corners with six equivalent BiO6 octahedra and edges with four equivalent KO8 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–28°. All Bi–O bond lengths are 2.18 Å. There are two inequivalent O sites. In the first O site, O is bonded in a 4-coordinate geometry to one K, one Sr, and two equivalent Bi atoms. In the second O site, O is bonded to two equivalent K, two equivalent Sr, and two equivalent Bi atoms to form a mixture of distorted edge and corner-sharing OK2Sr2Bi2 octahedra. The corner-sharing octahedral tilt angles are 0°.