Materials Data on Ca3Pr2Sb3O14 by Materials Project
Ca3Pr2Sb3O14 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six SbO6 octahedra. The corner-sharing octahedra tilt angles range from 57–58°. There are two shorter (2.31 Å) and four longer (2.33 Å) Ca–O bond lengths. In the second Ca2+ site, Ca2+ is bonded to eight O2- atoms to form CaO8 hexagonal bipyramids that share edges with six SbO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.25–2.64 Å. In the third Ca2+ site, Ca2+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Ca–O bond distances ranging from 2.34–2.86 Å. Pr+3.50+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Pr–O bond distances ranging from 2.34–2.82 Å. There are two inequivalent Sb5+ sites. In the first Sb5+ site, Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four equivalent SbO6 octahedra, and edges with two equivalent CaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 42–58°. There are two shorter (1.97 Å) and four longer (2.04 Å) Sb–O bond lengths. In the second Sb5+ site, Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with two equivalent CaO6 octahedra, corners with four SbO6 octahedra, and edges with two equivalent CaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 41–57°. There are a spread of Sb–O bond distances ranging from 1.97–2.04 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+ and two equivalent Sb5+ atoms. In the second O2- site, O2- is bonded to two Ca2+ and two equivalent Pr+3.50+ atoms to form OCa2Pr2 tetrahedra that share corners with ten OCa2Pr2 tetrahedra and edges with three OCa2PrSb tetrahedra. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, one Pr+3.50+, and two Sb5+ atoms. In the fourth O2- site, O2- is bonded to two Ca2+, one Pr+3.50+, and one Sb5+ atom to form a mixture of distorted edge and corner-sharing OCa2PrSb tetrahedra. In the fifth O2- site, O2- is bonded to one Ca2+, two equivalent Pr+3.50+, and one Sb5+ atom to form a mixture of distorted edge and corner-sharing OCaPr2Sb tetrahedra.