DOE OSTI2020
Dy2O3 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are three inequivalent Dy3+ sites. In the first Dy3+ site, Dy3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Dy–O bond distances ranging from 2.24–2.60 Å. In the second Dy3+ site, Dy3+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of Dy–O bond distances ranging from 2.24–2.75 Å. In the third Dy3+ site, Dy3+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing DyO6 octahedra. The corner-sharing octahedral tilt angles are 0°. There are a spread of Dy–O bond distances ranging from 2.21–2.48 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to five Dy3+ atoms to form distorted ODy5 square pyramids that share corners with seven ODy4 tetrahedra, corners with two equivalent ODy4 trigonal pyramids, edges with two equivalent ODy6 octahedra, edges with two equivalent ODy5 square pyramids, edges with three ODy4 tetrahedra, and edges with three equivalent ODy4 trigonal pyramids. In the second O2- site, O2- is bonded to four Dy3+ atoms to form distorted ODy4 trigonal pyramids that share a cornercorner with one ODy6 octahedra, corners with two equivalent ODy5 square pyramids, corners with nine ODy4 tetrahedra, corners with two equivalent ODy4 trigonal pyramids, edges with three equivalent ODy5 square pyramids, and edges with two equivalent ODy4 trigonal pyramids. The corner-sharing octahedral tilt angles are 37°. In the third O2- site, O2- is bonded to six Dy3+ atoms to form ODy6 octahedra that share corners with six ODy4 tetrahedra, corners with two equivalent ODy4 trigonal pyramids, edges with two equivalent ODy6 octahedra, edges with four equivalent ODy5 square pyramids, and edges with six ODy4 tetrahedra. In the fourth O2- site, O2- is bonded to four Dy3+ atoms to form ODy4 tetrahedra that share corners with two equivalent ODy6 octahedra, corners with two equivalent ODy5 square pyramids, corners with four ODy4 tetrahedra, corners with six equivalent ODy4 trigonal pyramids, an edgeedge with one ODy6 octahedra, edges with two equivalent ODy5 square pyramids, and an edgeedge with one ODy4 tetrahedra. The corner-sharing octahedral tilt angles are 13°. In the fifth O2- site, O2- is bonded to four Dy3+ atoms to form ODy4 tetrahedra that share a cornercorner with one ODy6 octahedra, corners with five equivalent ODy5 square pyramids, corners with four ODy4 tetrahedra, corners with three equivalent ODy4 trigonal pyramids, edges with two equivalent ODy6 octahedra, an edgeedge with one ODy5 square pyramid, and edges with two equivalent ODy4 tetrahedra. The corner-sharing octahedral tilt angles are 49°.