Materials Data on HoTa3O9 by Materials Project
HoTa3O9 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Ho3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ho–O bond distances ranging from 2.30–2.51 Å. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 32–50°. There are a spread of Ta–O bond distances ranging from 1.96–2.05 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form a mixture of edge and corner-sharing TaO6 octahedra. The corner-sharing octahedra tilt angles range from 34–50°. There are a spread of Ta–O bond distances ranging from 1.86–2.19 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two equivalent Ta5+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Ho3+ and two Ta5+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ho3+ and two equivalent Ta5+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Ho3+ and two equivalent Ta5+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to two Ta5+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Ho3+ and two equivalent Ta5+ atoms.