DOI: 10.17188/1677378
title: Materials Data on Y11Ta5O28 by Materials Project

description: Y11Ta5O28 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are six inequivalent Y3+ sites. In the first Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with two equivalent TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, an edgeedge with one YO8 hexagonal bipyramid, edges with two equivalent TaO6 octahedra, and edges with two equivalent YO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 57°. There are a spread of Y–O bond distances ranging from 2.29–2.41 Å. In the second Y3+ site, Y3+ is bonded to eight O2- atoms to form distorted YO8 hexagonal bipyramids that share edges with six TaO6 octahedra and edges with two equivalent YO7 pentagonal bipyramids. There are a spread of Y–O bond distances ranging from 2.15–2.59 Å. In the third Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with three TaO6 octahedra, edges with two equivalent TaO6 octahedra, and edges with three YO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 46–54°. There are a spread of Y–O bond distances ranging from 2.20–2.45 Å. In the fourth Y3+ site, Y3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.32–2.61 Å. In the fifth Y3+ site, Y3+ is bonded in a distorted body-centered cubic geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.26–2.77 Å. In the sixth Y3+ site, Y3+ is bonded to seven O2- atoms to form distorted YO7 pentagonal bipyramids that share corners with two equivalent TaO6 octahedra, a cornercorner with one YO7 pentagonal bipyramid, edges with two equivalent TaO6 octahedra, and edges with three YO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 51°. There are a spread of Y–O bond distances ranging from 2.23–2.43 Å. There are two inequivalent Ta+4.60+ sites. In the first Ta+4.60+ site, Ta+4.60+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with four equivalent TaO6 octahedra, corners with two equivalent YO7 pentagonal bipyramids, and edges with two equivalent YO8 hexagonal bipyramids. The corner-sharing octahedral tilt angles are 39°. There are four shorter (1.98 Å) and two longer (2.06 Å) Ta–O bond lengths. In the second Ta+4.60+ site, Ta+4.60+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with three TaO6 octahedra, corners with three YO7 pentagonal bipyramids, an edgeedge with one YO8 hexagonal bipyramid, and edges with three YO7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 39–63°. There are a spread of Ta–O bond distances ranging from 1.96–2.11 Å. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded to two Y3+ and two equivalent Ta+4.60+ atoms to form distorted OY2Ta2 tetrahedra that share corners with seven OY2Ta2 tetrahedra, corners with two equivalent OY2Ta2 trigonal pyramids, and an edgeedge with one OY4 tetrahedra. In the second O2- site, O2- is bonded to two Y3+ and two equivalent Ta+4.60+ atoms to form distorted OY2Ta2 trigonal pyramids that share corners with four OY2Ta2 tetrahedra and edges with three OY3Ta tetrahedra. In the third O2- site, O2- is bonded in a 2-coordinate geometry to two Y3+ and two Ta+4.60+ atoms. In the fourth O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share corners with eight OY4 tetrahedra, an edgeedge with one OY4 tetrahedra, and an edgeedge with one OY2Ta2 trigonal pyramid. In the fifth O2- site, O2- is bonded to four Y3+ atoms to form OY4 tetrahedra that share corners with nine OY2Ta2 tetrahedra, a cornercorner with one OY2Ta2 trigonal pyramid, and an edgeedge with one OY4 tetrahedra. In the sixth O2- site, O2- is bonded to three Y3+ and one Ta+4.60+ atom to form distorted OY3Ta tetrahedra that share corners with eight OY4 tetrahedra, a cornercorner with one OY2Ta2 trigonal pyramid, and edges with three OY3Ta tetrahedra. In the seventh O2- site, O2- is bonded to four Y3+ atoms to form a mixture of edge and corner-sharing OY4 tetrahedra. In the eighth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta+4.60+ atom. In the ninth O2- site, O2- is bonded to three Y3+ and one Ta+4.60+ atom to form distorted OY3Ta tetrahedra that share corners with nine OY2Ta2 tetrahedra, edges with two OY3Ta tetrahedra, and an edgeedge with one OY2Ta2 trigonal pyramid. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to three Y3+ and one Ta+4.60+ atom.