Materials Data on Ca2CoSi4NiO12 by Materials Project

Abstract

Ca2CoNiSi4O12 is Esseneite-derived structured and crystallizes in the monoclinic C2 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 2.34–2.78 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 2.34–2.78 Å. Co2+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six SiO4 tetrahedra and edges with two equivalent NiO6 octahedra. There are a spread of Co–O bond distances ranging from 2.08–2.16 Å. Ni2+ is bonded to six O2- atoms to form NiO6 octahedra that share corners with six SiO4 tetrahedra and edges with two equivalent CoO6 octahedra. There are a spread of Ni–O bond distances ranging from 2.08–2.14 Å. There are two inequivalent Si4+ sites. In the first Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one NiO6 octahedra, corners with two equivalent CoO6 octahedra, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–58°. There are a spread of Si–O bond distances ranging from 1.61–1.70 Å. In the second Si4+ site, Si4+ is bonded to four O2- atoms to form SiO4 tetrahedra that share a cornercorner with one CoO6 octahedra, corners with two equivalent NiO6 octahedra, and corners with two equivalent SiO4 tetrahedra. The corner-sharing octahedra tilt angles range from 35–59°. There are a spread of Si–O bond distances ranging from 1.61–1.70 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Co2+, and one Si4+ atom. In the second O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one Ni2+, and one Si4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Co2+, one Ni2+, and one Si4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Co2+, one Ni2+, and one Si4+ atom. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to two Ca2+ and two Si4+ atoms.