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Materials Data on Ho2Zr8O19 by Materials Project

Ho2Zr8O19 is alpha bismuth trifluoride-derived structured and crystallizes in the tetragonal P-4m2 space group. The structure is three-dimensional. Ho3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ho–O bond distances ranging from 2.10–2.32 Å. There are four inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Zr–O bond distances ranging from 2.14–2.31 Å. In the second Zr4+ site, Zr4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Zr–O bond distances ranging from 2.15–2.30 Å. In the third Zr4+ site, Zr4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Zr–O bond distances ranging from 2.17–2.29 Å. In the fourth Zr4+ site, Zr4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Zr–O bond distances ranging from 2.19–2.26 Å. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded to four Zr4+ atoms to form a mixture of edge and corner-sharing OZr4 tetrahedra. In the second O2- site, O2- is bonded to four Zr4+ atoms to form a mixture of edge and corner-sharing OZr4 tetrahedra. In the third O2- site, O2- is bonded to four Zr4+ atoms to form a mixture of edge and corner-sharing OZr4 tetrahedra. In the fourth O2- site, O2- is bonded to four equivalent Zr4+ atoms to form a mixture of edge and corner-sharing OZr4 tetrahedra. In the fifth O2- site, O2- is bonded to four Zr4+ atoms to form OZr4 tetrahedra that share corners with sixteen OZr4 tetrahedra and edges with six OHo2Zr2 tetrahedra. In the sixth O2- site, O2- is bonded to two equivalent Ho3+ and two equivalent Zr4+ atoms to form a mixture of edge and corner-sharing OHo2Zr2 tetrahedra. In the seventh O2- site, O2- is bonded to two equivalent Ho3+ and two equivalent Zr4+ atoms to form OHo2Zr2 tetrahedra that share corners with fourteen OZr4 tetrahedra and edges with five OHo2Zr2 tetrahedra. In the eighth O2- site, O2- is bonded to four equivalent Ho3+ atoms to form a mixture of edge and corner-sharing OHo4 tetrahedra. In the ninth O2- site, O2- is bonded to four Zr4+ atoms to form a mixture of edge and corner-sharing OZr4 tetrahedra. In the tenth O2- site, O2- is bonded to four Zr4+ atoms to form a mixture of edge and corner-sharing OZr4 tetrahedra. In the eleventh O2- site, O2- is bonded to four equivalent Zr4+ atoms to form a mixture of edge and corner-sharing OZr4 tetrahedra.

36 MATERIALS SCIENCE↗

Materials Data on Ho2Zr2O7 by Materials Project

Ho2Zr2O7 crystallizes in the orthorhombic Pmma space group. The structure is three-dimensional. there are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing HoO6 octahedra. The corner-sharing octahedral tilt angles are 68°. There are two shorter (2.27 Å) and four longer (2.29 Å) Ho–O bond lengths. In the second Ho3+ site, Ho3+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ho–O bond distances ranging from 2.17–2.31 Å. There are two inequivalent Zr4+ sites. In the first Zr4+ site, Zr4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Zr–O bond distances ranging from 2.16–2.58 Å. In the second Zr4+ site, Zr4+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Zr–O bond distances ranging from 2.21–2.35 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ho3+ and two equivalent Zr4+ atoms to form OHo2Zr2 tetrahedra that share corners with ten OHo2Zr2 tetrahedra and an edgeedge with one OZr4 tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Ho3+ and one Zr4+ atom. In the third O2- site, O2- is bonded to two equivalent Ho3+ and two equivalent Zr4+ atoms to form OHo2Zr2 tetrahedra that share corners with ten OHo2Zr2 tetrahedra and edges with five OZr4 tetrahedra. In the fourth O2- site, O2- is bonded to four Zr4+ atoms to form a mixture of edge and corner-sharing OZr4 tetrahedra. In the fifth O2- site, O2- is bonded to one Ho3+ and three Zr4+ atoms to form a mixture of edge and corner-sharing OHoZr3 tetrahedra.

36 MATERIALS SCIENCE↗

Materials Data on Ho2Zr2O7 by Materials Project

Ho2Zr2O7 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Ho3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are two shorter (2.29 Å) and six longer (2.50 Å) Ho–O bond lengths. Zr4+ is bonded to six equivalent O2- atoms to form corner-sharing ZrO6 octahedra. The corner-sharing octahedral tilt angles are 55°. All Zr–O bond lengths are 2.11 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Ho3+ and two equivalent Zr4+ atoms to form a mixture of distorted corner and edge-sharing OHo2Zr2 tetrahedra. In the second O2- site, O2- is bonded to four equivalent Ho3+ atoms to form a mixture of corner and edge-sharing OHo4 tetrahedra.

36 MATERIALS SCIENCE↗