Materials Data on Ca2TaNiO6 by Materials Project

Abstract

Ca2TaNiO6 is Orthorhombic Perovskite-derived structured and 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 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.78 Å. In the second Ca2+ site, Ca2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.35–2.67 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 NiO6 octahedra. The corner-sharing octahedra tilt angles range from 27–30°. There are a spread of Ta–O bond distances ranging from 1.98–2.00 Å. Ni3+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with two equivalent NiO6 octahedra and corners with four equivalent TaO6 octahedra. The corner-sharing octahedra tilt angles range from 27–32°. There are a spread of Ni–O bond distances ranging from 2.00–2.11 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 Ni3+ atom. In the second O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+, one Ta5+, and one Ni3+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two equivalent Ta5+ atoms. In the fourth O2- site, O2- is bonded to two Ca2+ and two equivalent Ni3+ atoms to form distorted corner-sharing OCa2Ni2 tetrahedra.