DOI: 10.17188/1742201
title: Materials Data on Ba2CaCeGd2Ti2(CuO7)2 by Materials Project

description: Ba2CaGd2CeTi2(CuO7)2 crystallizes in the tetragonal P4mm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, faces with four equivalent BaO12 cuboctahedra, faces with four equivalent TiO6 octahedra, and faces with four equivalent CuO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.79–3.09 Å. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form distorted BaO12 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, faces with four equivalent BaO12 cuboctahedra, faces with four equivalent TiO6 octahedra, and faces with four equivalent CuO5 square pyramids. There are a spread of Ba–O bond distances ranging from 2.80–3.16 Å. Ca2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ca–O bond distances ranging from 2.33–2.80 Å. There are two inequivalent Gd3+ sites. In the first Gd3+ site, Gd3+ is bonded in a 1-coordinate geometry to nine O2- atoms. There are a spread of Gd–O bond distances ranging from 2.12–2.78 Å. In the second Gd3+ site, Gd3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.38 Å) and four longer (2.47 Å) Gd–O bond lengths. Ce4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.29 Å) and four longer (2.52 Å) Ce–O bond lengths. There are two inequivalent Ti4+ sites. In the first Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four equivalent TiO6 octahedra, a cornercorner with one CuO5 square pyramid, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 10°. There are a spread of Ti–O bond distances ranging from 1.86–2.20 Å. In the second Ti4+ site, Ti4+ is bonded to six O2- atoms to form TiO6 octahedra that share corners with four equivalent TiO6 octahedra, a cornercorner with one CuO5 square pyramid, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 11°. There are a spread of Ti–O bond distances ranging from 1.86–2.09 Å. There are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one TiO6 octahedra, corners with four equivalent CuO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.96 Å) and one longer (2.39 Å) Cu–O bond lengths. In the second Cu2+ site, Cu2+ is bonded to five O2- atoms to form CuO5 square pyramids that share a cornercorner with one TiO6 octahedra, corners with four equivalent CuO5 square pyramids, and faces with four equivalent BaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. There are four shorter (1.96 Å) and one longer (2.45 Å) Cu–O bond lengths. There are nine inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to four equivalent Ba2+, one Ti4+, and one Cu2+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Ba2+, one Ti4+, and one Cu2+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, two equivalent Ca2+, and two equivalent Ti4+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, two equivalent Gd3+, and two equivalent Ti4+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to four equivalent Ca2+, one Gd3+, and one Ti4+ atom. In the sixth O2- site, O2- is bonded in a distorted linear geometry to one Ca2+, four equivalent Gd3+, and one Ti4+ atom. In the seventh O2- site, O2- is bonded to two equivalent Gd3+ and two equivalent Ce4+ atoms to form a mixture of edge and corner-sharing OCe2Gd2 tetrahedra. In the eighth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Gd3+, and two equivalent Cu2+ atoms. In the ninth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Ce4+, and two equivalent Cu2+ atoms.