DOE OSTI2020
Ca3Co2(WO6)2 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are three 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 2.35–2.74 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 2.33–2.59 Å. In the third 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 2.35–2.75 Å. There are two inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 20–32°. There are a spread of W–O bond distances ranging from 1.87–2.04 Å. In the second W6+ site, W6+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six CoO6 octahedra. The corner-sharing octahedra tilt angles range from 21–31°. There are a spread of W–O bond distances ranging from 1.89–2.04 Å. There are two inequivalent Co3+ sites. In the first Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 20–32°. There are a spread of Co–O bond distances ranging from 1.87–2.09 Å. In the second Co3+ site, Co3+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 21–31°. There are a spread of Co–O bond distances ranging from 1.83–2.11 Å. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+, one W6+, and one Co3+ atom. In the second O2- site, O2- is bonded to two Ca2+, one W6+, and one Co3+ atom to form distorted corner-sharing OCa2CoW trigonal pyramids. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one W6+, and one Co3+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one W6+, and one Co3+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one W6+, and one Co3+ atom. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one W6+, and one Co3+ atom. In the seventh O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one W6+, and one Co3+ atom. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to three Ca2+, one W6+, and one Co3+ atom. In the ninth O2- site, O2- is bonded to two Ca2+, one W6+, and one Co3+ atom to form distorted corner-sharing OCa2CoW tetrahedra. In the tenth O2- site, O2- is bonded in a distorted see-saw-like geometry to two Ca2+, one W6+, and one Co3+ atom. In the eleventh O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one W6+, and one Co3+ atom. In the twelfth O2- site, O2- is bonded in a distorted T-shaped geometry to one Ca2+, one W6+, and one Co3+ atom.