DOI: 10.17188/1696263
title: Materials Data on CaZrNbFeO7 by Materials Project

description: CaZrNbFeO7 crystallizes in the monoclinic Cc space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first 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 2.46–2.66 Å. In the second 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 2.41–2.64 Å. There are two inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Zr–O bond distances ranging from 2.06–2.58 Å. In the second Zr4+ site, Zr4+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Zr–O bond distances ranging from 2.04–2.65 Å. There are two inequivalent Nb5+ sites. In the first Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra and corners with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 43–46°. There are a spread of Nb–O bond distances ranging from 1.93–2.06 Å. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with two equivalent NbO6 octahedra and corners with two equivalent FeO6 octahedra. The corner-sharing octahedra tilt angles range from 32–51°. There are a spread of Nb–O bond distances ranging from 1.88–2.14 Å. There are two inequivalent Fe3+ sites. In the first Fe3+ site, Fe3+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Fe–O bond distances ranging from 1.87–2.60 Å. In the second Fe3+ site, Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with four NbO6 octahedra. The corner-sharing octahedra tilt angles range from 32–51°. There are a spread of Fe–O bond distances ranging from 1.98–2.08 Å. There are fourteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Ca2+, one Nb5+, and two Fe3+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ca2+, one Nb5+, and one Fe3+ atom. In the third O2- site, O2- is bonded to two Ca2+, one Zr4+, and one Fe3+ atom to form distorted OCa2ZrFe tetrahedra that share corners with seven OCaZr2Nb tetrahedra and an edgeedge with one OCaNbFe2 trigonal pyramid. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to two Ca2+, one Zr4+, and one Nb5+ atom. In the fifth O2- site, O2- is bonded to one Ca2+, two Zr4+, and one Nb5+ atom to form a mixture of distorted edge and corner-sharing OCaZr2Nb tetrahedra. In the sixth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Zr4+, and one Fe3+ atom. In the seventh O2- site, O2- is bonded to one Ca2+, one Nb5+, and two Fe3+ atoms to form a mixture of distorted edge and corner-sharing OCaNbFe2 trigonal pyramids. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Nb5+, and one Fe3+ atom. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Ca2+, two Zr4+, and one Nb5+ atom. In the tenth O2- site, O2- is bonded in a 2-coordinate geometry to one Ca2+, two Zr4+, and one Nb5+ atom. In the eleventh O2- site, O2- is bonded in a distorted trigonal planar geometry to one Zr4+, one Nb5+, and one Fe3+ atom. In the twelfth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to one Zr4+ and two Nb5+ atoms. In the thirteenth O2- site, O2- is bonded to two Ca2+, one Zr4+, and one Fe3+ atom to form distorted OCa2ZrFe tetrahedra that share corners with five OCa2ZrFe tetrahedra, an edgeedge with one OCa2ZrFe tetrahedra, and an edgeedge with one OCaNbFe2 trigonal pyramid. In the fourteenth O2- site, O2- is bonded to two Ca2+, one Zr4+, and one Fe3+ atom to form distorted OCa2ZrFe tetrahedra that share corners with four OCa2ZrFe tetrahedra, corners with two equivalent OCaNbFe2 trigonal pyramids, and edges with two OCaZr2Nb tetrahedra.