Materials Data on CeTa3O9 by Materials Project
CeTa3O9 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ce3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Ce–O bond distances ranging from 2.44–2.59 Å. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to seven O2- atoms to form TaO7 pentagonal bipyramids that share a cornercorner with one TaO6 octahedra, corners with two equivalent TaO7 pentagonal bipyramids, an edgeedge with one TaO6 octahedra, and edges with two equivalent TaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 37°. There are a spread of Ta–O bond distances ranging from 1.93–2.24 Å. In the second Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with two equivalent TaO6 octahedra, corners with two equivalent TaO7 pentagonal bipyramids, and edges with two equivalent TaO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 31°. There are a spread of Ta–O bond distances ranging from 1.98–2.01 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Ce3+ and two equivalent Ta5+ atoms. In the second O2- site, O2- is bonded in a 4-coordinate geometry to two equivalent Ce3+ and two Ta5+ atoms. In the third O2- site, O2- is bonded in a 3-coordinate geometry to three Ta5+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Ce3+ and two equivalent Ta5+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to one Ce3+ and two equivalent Ta5+ atoms. In the sixth O2- site, O2- is bonded in a linear geometry to two equivalent Ta5+ atoms.