Materials Data on Ca2TaBiO6 by Materials Project

Abstract

Ca2TaBiO6 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded in a 4-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.24–2.88 Å. In the second Ca2+ site, Ca2+ is bonded in a 4-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.89 Å. Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with two equivalent TaO6 octahedra and corners with four equivalent BiO6 octahedra. The corner-sharing octahedra tilt angles range from 36–39°. There are a spread of Ta–O bond distances ranging from 1.98–2.14 Å. Bi3+ is bonded to six O2- atoms to form BiO6 octahedra that share corners with two equivalent BiO6 octahedra and corners with four equivalent TaO6 octahedra. The corner-sharing octahedra tilt angles range from 37–50°. There are a spread of Bi–O bond distances ranging from 2.25–2.43 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+, one Ta5+, and one Bi3+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+, one Ta5+, and one Bi3+ atom. In the third O2- site, O2- is bonded to two Ca2+ and two equivalent Ta5+ atoms to form distorted OCa2Ta2 tetrahedra that share corners with two equivalent OCa2Ta2 tetrahedra and corners with two equivalent OCa2Bi2 trigonal pyramids. In the fourth O2- site, O2- is bonded to two Ca2+ and two equivalent Bi3+ atoms to form distorted OCa2Bi2 trigonal pyramids that share corners with two equivalent OCa2Ta2 tetrahedra and corners with two equivalent OCa2Bi2 trigonal pyramids.