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Materials Data on BaHo2ZnO5 by Materials Project

BaHo2ZnO5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Ba2+ is bonded in a 11-coordinate geometry to eleven O2- atoms. There are a spread of Ba–O bond distances ranging from 2.74–3.32 Å. There are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven O2- atoms to form distorted HoO7 pentagonal bipyramids that share corners with five equivalent ZnO5 trigonal bipyramids, edges with five HoO7 pentagonal bipyramids, an edgeedge with one ZnO5 trigonal bipyramid, and a faceface with one HoO7 pentagonal bipyramid. There are a spread of Ho–O bond distances ranging from 2.30–2.37 Å. In the second Ho3+ site, Ho3+ is bonded to seven O2- atoms to form distorted HoO7 pentagonal bipyramids that share corners with four equivalent HoO7 pentagonal bipyramids, edges with three equivalent HoO7 pentagonal bipyramids, edges with two equivalent ZnO5 trigonal bipyramids, a faceface with one HoO7 pentagonal bipyramid, and a faceface with one ZnO5 trigonal bipyramid. There are a spread of Ho–O bond distances ranging from 2.30–2.39 Å. Zn2+ is bonded to five O2- atoms to form ZnO5 trigonal bipyramids that share corners with five equivalent HoO7 pentagonal bipyramids, edges with three HoO7 pentagonal bipyramids, and a faceface with one HoO7 pentagonal bipyramid. There are a spread of Zn–O bond distances ranging from 2.00–2.15 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to three equivalent Ba2+, two Ho3+, and one Zn2+ atom to form a mixture of distorted corner and edge-sharing OBa3Ho2Zn octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, three Ho3+, and one Zn2+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, three Ho3+, and one Zn2+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Ba5Ho8Zn4O21 by Materials Project

Ba5Ho8Zn4O21 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 2.67–3.26 Å. In the second Ba2+ site, Ba2+ is bonded in a distorted q6 geometry to ten O2- atoms. There are two shorter (2.87 Å) and eight longer (2.93 Å) Ba–O bond lengths. There are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven O2- atoms to form distorted HoO7 pentagonal bipyramids that share corners with three HoO7 pentagonal bipyramids, corners with two equivalent ZnO5 trigonal bipyramids, edges with three equivalent HoO7 pentagonal bipyramids, edges with two equivalent ZnO5 trigonal bipyramids, and faces with two equivalent HoO7 pentagonal bipyramids. There are a spread of Ho–O bond distances ranging from 2.29–2.43 Å. In the second Ho3+ site, Ho3+ is bonded to seven O2- atoms to form distorted HoO7 pentagonal bipyramids that share corners with two equivalent HoO7 pentagonal bipyramids, corners with two equivalent ZnO5 trigonal bipyramids, edges with five HoO7 pentagonal bipyramids, an edgeedge with one ZnO5 trigonal bipyramid, and a faceface with one ZnO5 trigonal bipyramid. There are a spread of Ho–O bond distances ranging from 2.29–2.49 Å. Zn2+ is bonded to five O2- atoms to form distorted ZnO5 trigonal bipyramids that share corners with four HoO7 pentagonal bipyramids, edges with three HoO7 pentagonal bipyramids, and a faceface with one HoO7 pentagonal bipyramid. There are a spread of Zn–O bond distances ranging from 2.00–2.14 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ba2+, three Ho3+, and one Zn2+ atom. In the second O2- site, O2- is bonded in a 6-coordinate geometry to two Ba2+, three Ho3+, and one Zn2+ atom. In the third O2- site, O2- is bonded to four equivalent Ba2+, one Ho3+, and one Zn2+ atom to form a mixture of distorted edge and corner-sharing OBa4HoZn octahedra. The corner-sharing octahedral tilt angles are 6°. In the fourth O2- site, O2- is bonded to two equivalent Ba2+ and four equivalent Ho3+ atoms to form distorted corner-sharing OBa2Ho4 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗