DOE OSTI2020
Ba2YSb3O8 crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. Ba2+ is bonded in a 12-coordinate geometry to eight O2- atoms. There are four shorter (2.96 Å) and four longer (3.11 Å) Ba–O bond lengths. Y3+ is bonded in a body-centered cubic geometry to eight equivalent O2- atoms. All Y–O bond lengths are 2.61 Å. There are two inequivalent Sb3+ sites. In the first Sb3+ site, Sb3+ is bonded to five O2- atoms to form SbO5 square pyramids that share a cornercorner with one SbO6 octahedra and corners with four equivalent SbO5 square pyramids. The corner-sharing octahedral tilt angles are 0°. There are one shorter (2.09 Å) and four longer (2.20 Å) Sb–O bond lengths. In the second Sb3+ site, Sb3+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with four equivalent SbO6 octahedra and corners with two equivalent SbO5 square pyramids. The corner-sharing octahedral tilt angles are 0°. There are four shorter (2.19 Å) and two longer (2.31 Å) Sb–O bond lengths. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted see-saw-like geometry to two equivalent Y3+ and two equivalent Sb3+ atoms. In the second O2- site, O2- is bonded to four equivalent Ba2+ and two equivalent Sb3+ atoms to form a mixture of distorted edge, face, and corner-sharing OBa4Sb2 octahedra. The corner-sharing octahedra tilt angles range from 0–54°. In the third O2- site, O2- is bonded to four equivalent Ba2+ and two Sb3+ atoms to form a mixture of distorted edge, face, and corner-sharing OBa4Sb2 octahedra. The corner-sharing octahedra tilt angles range from 0–54°.