Materials Data on Ba3Co8Sn3O20 by Materials Project

Abstract

Ba3Co8Sn3O20 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 5-coordinate geometry to seven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.69–3.23 Å. In the second Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are two shorter (2.71 Å) and four longer (2.89 Å) Ba–O bond lengths. There are two inequivalent Co+2.75+ sites. In the first Co+2.75+ site, Co+2.75+ is bonded to four O2- atoms to form CoO4 tetrahedra that share a cornercorner with one SnO6 octahedra and corners with four CoO4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are a spread of Co–O bond distances ranging from 1.85–1.93 Å. In the second Co+2.75+ site, Co+2.75+ is bonded to four O2- atoms to form CoO4 tetrahedra that share corners with three SnO6 octahedra and corners with three equivalent CoO4 tetrahedra. The corner-sharing octahedra tilt angles range from 47–61°. There are a spread of Co–O bond distances ranging from 1.86–1.97 Å. There are two inequivalent Sn4+ sites. In the first Sn4+ site, Sn4+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with four equivalent CoO4 tetrahedra and edges with four equivalent SnO6 octahedra. There are two shorter (2.07 Å) and four longer (2.10 Å) Sn–O bond lengths. In the second Sn4+ site, Sn4+ is bonded to six O2- atoms to form SnO6 octahedra that share corners with six CoO4 tetrahedra and edges with three SnO6 octahedra. There are a spread of Sn–O bond distances ranging from 2.05–2.21 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to two Co+2.75+ and one Sn4+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Ba2+ and two Co+2.75+ atoms. In the third O2- site, O2- is bonded to two Ba2+ and two Co+2.75+ atoms to form a mixture of distorted edge and corner-sharing OBa2Co2 tetrahedra. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ba2+, one Co+2.75+, and two Sn4+ atoms. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ba2+ and two equivalent Co+2.75+ atoms. In the sixth O2- site, O2- is bonded to one Ba2+ and three Sn4+ atoms to form distorted OBaSn3 tetrahedra that share corners with three OBa2Co2 tetrahedra and an edgeedge with one OBaSn3 tetrahedra.