Materials Data on Ca3Nd4Nb6(FeO14)2 by Materials Project

Abstract

Ca3Nd4Nb6(FeO14)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded to eight O atoms to form distorted CaO8 hexagonal bipyramids that share an edgeedge with one CaO8 hexagonal bipyramid, edges with four NdO8 hexagonal bipyramids, edges with two FeO6 octahedra, and edges with four NbO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.27–2.76 Å. In the second Ca site, Ca is bonded to eight O atoms to form distorted CaO8 hexagonal bipyramids that share edges with two equivalent CaO8 hexagonal bipyramids, edges with four NdO8 hexagonal bipyramids, and edges with six NbO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.26–2.70 Å. There are three inequivalent Nd sites. In the first Nd site, Nd is bonded to eight O atoms to form distorted NdO8 hexagonal bipyramids that share edges with two NdO8 hexagonal bipyramids, edges with three CaO8 hexagonal bipyramids, edges with two FeO6 octahedra, and edges with four NbO6 octahedra. There are a spread of Nd–O bond distances ranging from 2.27–2.70 Å. In the second Nd site, Nd is bonded to eight O atoms to form distorted NdO8 hexagonal bipyramids that share edges with two equivalent CaO8 hexagonal bipyramids, edges with two equivalent NdO8 hexagonal bipyramids, edges with two equivalent FeO6 octahedra, and edges with four NbO6 octahedra. There are a spread of Nd–O bond distances ranging from 2.19–2.64 Å. In the third Nd site, Nd is bonded to eight O atoms to form NdO8 hexagonal bipyramids that share edges with two equivalent NdO8 hexagonal bipyramids, edges with four CaO8 hexagonal bipyramids, edges with two equivalent FeO6 octahedra, and edges with four NbO6 octahedra. There are a spread of Nd–O bond distances ranging from 2.31–2.60 Å. There are four inequivalent Nb sites. In the first Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four NbO6 octahedra, edges with two equivalent NdO8 hexagonal bipyramids, and edges with four CaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 43–46°. There are a spread of Nb–O bond distances ranging from 2.00–2.03 Å. In the second Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with two equivalent FeO6 octahedra, corners with four NbO6 octahedra, edges with two equivalent CaO8 hexagonal bipyramids, and edges with two equivalent NdO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 40–45°. There are two shorter (2.00 Å) and four longer (2.01 Å) Nb–O bond lengths. In the third Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with two FeO6 octahedra, corners with four NbO6 octahedra, edges with two NdO8 hexagonal bipyramids, and edges with three CaO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 37–48°. There are a spread of Nb–O bond distances ranging from 1.95–2.07 Å. In the fourth Nb site, Nb is bonded to six O atoms to form NbO6 octahedra that share corners with two FeO6 octahedra, corners with four NbO6 octahedra, an edgeedge with one CaO8 hexagonal bipyramid, and edges with four NdO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 37–48°. There are a spread of Nb–O bond distances ranging from 1.94–2.08 Å. There are two inequivalent Fe sites. In the first Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six NbO6 octahedra, edges with two equivalent CaO8 hexagonal bipyramids, and edges with four NdO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 43–48°. There are a spread of Fe–O bond distances ranging from 1.96–2.06 Å. In the second Fe site, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with six NbO6 octahedra, edges with two equivalent CaO8 hexagonal bipyramids, and edges with four NdO8 hexagonal bipyramids. The corner-sharing octahedra tilt angles range from 44–46°. There are two shorter (1.99 Å) and four longer (2.02 Å) Fe–O bond lengths. There are fourteen inequivalent O sites. In the first O site, O is bonded in a distorted trigonal non-coplanar geometry to one Ca and two Nb atoms. In the second O site, O is bonded in a 3-coordinate geometry to one Nd and two Nb atoms. In the third O site, O is bonded in a trigonal planar geometry to one Ca and two Nd atoms. In the fourth O site, O is bonded in a 4-coordinate geometry to one Ca, one Nd, one Nb, and one Fe atom. In the fifth O site, O is bonded in a 4-coordinate geometry to two Nd, one Nb, and one Fe atom. In the sixth O site, O is bonded in a 4-coordinate geometry to one Ca, one Nd, one Nb, and one Fe atom. In the seventh O site, O is bonded in a 4-coordinate geometry to two Nd, one Nb, and one Fe atom. In the eighth O site, O is bonded in a 4-coordinate geometry to one Ca, one Nd, one Nb, and one Fe atom. In the ninth O site, O is bonded to one Ca, one Nd, and two Nb atoms to form distorted OCaNdNb2 tetrahedra that share corners with four OCaNdNb2 tetrahedra and an edgeedge with one OCa2Nd2 tetrahedra. In the tenth O site, O is bonded to two Ca and two Nd atoms to form a mixture of edge and corner-sharing OCa2Nd2 tetrahedra. In the eleventh O site, O is bonded in a 4-coordinate geometry to one Ca, one Nd, one Nb, and one Fe atom. In the twelfth O site, O is bonded in a distorted trigonal non-coplanar geometry to one Nd and two Nb atoms. In the thirteenth O site, O is bonded in a 4-coordinate geometry to two Ca and two Nb atoms. In the fourteenth O site, O is bonded in a 4-coordinate geometry to one Ca, one Nd, and two Nb atoms.