Materials Data on Sr6La2Ta3Al5O24 by Materials Project

Abstract

Sr6La2Ta3Al5O24 is (Cubic) Perovskite-derived structured and crystallizes in the trigonal R32 space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with three equivalent LaO12 cuboctahedra, corners with nine SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four AlO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.76–2.80 Å. In the second Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with three equivalent LaO12 cuboctahedra, corners with nine SrO12 cuboctahedra, faces with three equivalent SrO12 cuboctahedra, faces with three equivalent LaO12 cuboctahedra, faces with three equivalent TaO6 octahedra, and faces with five AlO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.72–2.86 Å. In the third Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, faces with four TaO6 octahedra, and faces with four equivalent AlO6 octahedra. There are nine shorter (2.76 Å) and three longer (2.77 Å) Sr–O bond lengths. La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with six SrO12 cuboctahedra, corners with six equivalent LaO12 cuboctahedra, faces with three equivalent SrO12 cuboctahedra, faces with three equivalent LaO12 cuboctahedra, a faceface with one TaO6 octahedra, and faces with seven AlO6 octahedra. There are a spread of La–O bond distances ranging from 2.60–2.82 Å. There are two inequivalent Ta5+ sites. In the first Ta5+ site, Ta5+ is bonded to six O2- atoms to form TaO6 octahedra that share corners with six AlO6 octahedra, a faceface with one LaO12 cuboctahedra, and faces with seven SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There is three shorter (1.99 Å) and three longer (2.00 Å) Ta–O bond length. In the second Ta5+ site, Ta5+ is bonded to six equivalent O2- atoms to form TaO6 octahedra that share corners with six equivalent AlO6 octahedra and faces with eight SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Ta–O bond lengths are 1.99 Å. There are three inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six equivalent O2- atoms to form AlO6 octahedra that share corners with six equivalent AlO6 octahedra, faces with two equivalent SrO12 cuboctahedra, and faces with six equivalent LaO12 cuboctahedra. The corner-sharing octahedral tilt angles are 2°. All Al–O bond lengths are 1.94 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with three equivalent TaO6 octahedra, corners with three equivalent AlO6 octahedra, faces with four SrO12 cuboctahedra, and faces with four equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 1–2°. All Al–O bond lengths are 1.93 Å. In the third Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six TaO6 octahedra and faces with eight SrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 0°. All Al–O bond lengths are 1.92 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to one Sr2+, three equivalent La3+, and two Al3+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to three Sr2+, one La3+, one Ta5+, and one Al3+ atom. In the third O2- site, O2- is bonded in a distorted linear geometry to four Sr2+, one Ta5+, and one Al3+ atom. In the fourth O2- site, O2- is bonded in a distorted linear geometry to four Sr2+, one Ta5+, and one Al3+ atom.