Materials Data on Dy3TaO7 by Materials Project

Abstract

Dy3TaO7 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent Dy3+ sites. In the first Dy3+ site, Dy3+ is bonded to seven O2- atoms to form distorted DyO7 pentagonal bipyramids that share corners with two equivalent TaO6 octahedra, corners with three equivalent DyO7 pentagonal bipyramids, edges with two equivalent TaO6 octahedra, and edges with two equivalent DyO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 42°. There are a spread of Dy–O bond distances ranging from 2.22–2.65 Å. In the second Dy3+ site, Dy3+ is bonded in a body-centered cubic geometry to eight O2- atoms. There are four shorter (2.36 Å) and four longer (2.66 Å) Dy–O bond lengths. Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with two equivalent TaO6 octahedra, corners with four equivalent DyO7 pentagonal bipyramids, and edges with four equivalent DyO7 pentagonal bipyramids. The corner-sharing octahedral tilt angles are 34°. There is two shorter (1.97 Å) and four longer (2.00 Å) Ta–O bond length. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four Dy3+ atoms to form a mixture of edge and corner-sharing ODy4 tetrahedra. In the second O2- site, O2- is bonded in a 4-coordinate geometry to three Dy3+ and one Ta5+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Dy3+ and two equivalent Ta5+ atoms.