Materials Data on Ba5Lu8Ni4O21 by Materials Project
Ba5Lu8Ni4O21 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 10-coordinate geometry to ten O2- atoms. There are a spread of Ba–O bond distances ranging from 2.69–3.23 Å. In the second Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to ten O2- atoms. There are two shorter (2.83 Å) and eight longer (2.88 Å) Ba–O bond lengths. There are two inequivalent Lu3+ sites. In the first Lu3+ site, Lu3+ is bonded to seven O2- atoms to form distorted LuO7 pentagonal bipyramids that share corners with three LuO7 pentagonal bipyramids, corners with two equivalent NiO5 trigonal bipyramids, edges with three equivalent LuO7 pentagonal bipyramids, edges with two equivalent NiO5 trigonal bipyramids, and faces with two equivalent LuO7 pentagonal bipyramids. There are a spread of Lu–O bond distances ranging from 2.25–2.39 Å. In the second Lu3+ site, Lu3+ is bonded to seven O2- atoms to form distorted LuO7 pentagonal bipyramids that share corners with two equivalent LuO7 pentagonal bipyramids, corners with two equivalent NiO5 trigonal bipyramids, edges with five LuO7 pentagonal bipyramids, an edgeedge with one NiO5 trigonal bipyramid, and a faceface with one NiO5 trigonal bipyramid. There are a spread of Lu–O bond distances ranging from 2.23–2.37 Å. Ni2+ is bonded to five O2- atoms to form NiO5 trigonal bipyramids that share corners with four LuO7 pentagonal bipyramids, edges with three LuO7 pentagonal bipyramids, and a faceface with one LuO7 pentagonal bipyramid. There are a spread of Ni–O bond distances ranging from 2.01–2.08 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 6-coordinate geometry to two Ba2+, three Lu3+, and one Ni2+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, three Lu3+, and one Ni2+ atom. In the third O2- site, O2- is bonded to two equivalent Ba2+ and four equivalent Lu3+ atoms to form distorted corner-sharing OBa2Lu4 octahedra. The corner-sharing octahedral tilt angles are 0°. In the fourth O2- site, O2- is bonded to four equivalent Ba2+, one Lu3+, and one Ni2+ atom to form a mixture of distorted edge and corner-sharing OBa4LuNi octahedra. The corner-sharing octahedral tilt angles are 4°.