DOI: 10.17188/1745484
title: Materials Data on Sr4CeNd3Nb2(CuO5)4 by Materials Project

description: Sr4Nd3CeNb2(CuO5)4 crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are four inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with eight SrO12 cuboctahedra, faces with five SrO12 cuboctahedra, faces with four NbO6 octahedra, and faces with four CuO5 square pyramids. There are a spread of Sr–O bond distances ranging from 2.79–3.07 Å. In the second Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with eight SrO12 cuboctahedra, faces with five SrO12 cuboctahedra, faces with four NbO6 octahedra, and faces with four CuO5 square pyramids. There are a spread of Sr–O bond distances ranging from 2.74–3.09 Å. In the third Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with eight SrO12 cuboctahedra, faces with five SrO12 cuboctahedra, faces with four NbO6 octahedra, and faces with four CuO5 square pyramids. There are a spread of Sr–O bond distances ranging from 2.74–3.09 Å. In the fourth Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with eight SrO12 cuboctahedra, faces with five SrO12 cuboctahedra, faces with four NbO6 octahedra, and faces with four CuO5 square pyramids. There are a spread of Sr–O bond distances ranging from 2.74–3.09 Å. There are two inequivalent Nd3+ sites. In the first Nd3+ site, Nd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.39 Å) and four longer (2.60 Å) Nd–O bond lengths. In the second Nd3+ site, Nd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.38 Å) and four longer (2.61 Å) Nd–O bond lengths. Ce4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.26 Å) and four longer (2.62 Å) Ce–O bond lengths. 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 four equivalent NbO6 octahedra, corners with two CuO5 square pyramids, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There is five shorter (1.98 Å) and one longer (1.99 Å) Nb–O bond length. In the second Nb5+ site, Nb5+ is bonded to six O2- atoms to form NbO6 octahedra that share corners with four equivalent NbO6 octahedra, corners with two CuO5 square pyramids, and faces with eight SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There is five shorter (1.98 Å) and one longer (1.99 Å) Nb–O bond length. There are four inequivalent Cu+2.25+ sites. In the first Cu+2.25+ site, Cu+2.25+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one NbO6 octahedra, corners with four equivalent CuO5 square pyramids, and faces with four SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.98 Å) and one longer (2.16 Å) Cu–O bond lengths. In the second Cu+2.25+ site, Cu+2.25+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one NbO6 octahedra, corners with four equivalent CuO5 square pyramids, and faces with four SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.98 Å) and one longer (2.16 Å) Cu–O bond lengths. In the third Cu+2.25+ site, Cu+2.25+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one NbO6 octahedra, corners with four equivalent CuO5 square pyramids, and faces with four SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.98 Å) and one longer (2.16 Å) Cu–O bond lengths. In the fourth Cu+2.25+ site, Cu+2.25+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one NbO6 octahedra, corners with four equivalent CuO5 square pyramids, and faces with four SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.98 Å) and one longer (2.15 Å) Cu–O bond lengths. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+, one Nb5+, and one Cu+2.25+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+, one Nb5+, and one Cu+2.25+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+, one Nb5+, and one Cu+2.25+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+, one Nb5+, and one Cu+2.25+ atom. In the fifth O2- site, O2- is bonded to two Sr2+, one Nd3+, one Ce4+, and two Cu+2.25+ atoms to form distorted OSr2CeNdCu2 octahedra that share corners with two equivalent OSr2CeNdCu2 octahedra, corners with six equivalent OCeNd3 tetrahedra, edges with two equivalent OSr2CeNdCu2 octahedra, an edgeedge with one OCeNd3 tetrahedra, and faces with four equivalent OSr2CeNdCu2 octahedra. The corner-sharing octahedral tilt angles are 9°. In the sixth O2- site, O2- is bonded to two Sr2+, two equivalent Nd3+, and two Cu+2.25+ atoms to form distorted OSr2Nd2Cu2 octahedra that share corners with two equivalent OSr2Nd2Cu2 octahedra, corners with six equivalent OCeNd3 tetrahedra, edges with two equivalent OSr2Nd2Cu2 octahedra, an edgeedge with one OCeNd3 tetrahedra, and faces with four equivalent OSr2Nd2Cu2 octahedra. The corner-sharing octahedral tilt angles are 8°. In the seventh O2- site, O2- is bonded to three Nd3+ and one Ce4+ atom to form OCeNd3 tetrahedra that share corners with twelve OSr2CeNdCu2 octahedra, corners with four equivalent OCeNd3 tetrahedra, edges with two OSr2CeNdCu2 octahedra, and edges with four equivalent OCeNd3 tetrahedra. The corner-sharing octahedra tilt angles range from 7–70°. In the eighth O2- site, O2- is bonded in a linear geometry to four Sr2+ and two Nb5+ atoms.