Materials Data on La7YAl8O24 by Materials Project

Abstract

La7YAl8O24 is (Cubic) Perovskite-derived structured and crystallizes in the cubic Pm-3m space group. The structure is three-dimensional. there are three inequivalent La3+ sites. In the first La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with twelve LaO12 cuboctahedra, faces with two equivalent YO12 cuboctahedra, faces with four equivalent LaO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. There are four shorter (2.68 Å) and eight longer (2.69 Å) La–O bond lengths. In the second La3+ site, La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share corners with four equivalent YO12 cuboctahedra, corners with eight equivalent LaO12 cuboctahedra, faces with six LaO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. There are eight shorter (2.69 Å) and four longer (2.71 Å) La–O bond lengths. In the third La3+ site, La3+ is bonded to twelve equivalent O2- atoms to form LaO12 cuboctahedra that share corners with twelve equivalent LaO12 cuboctahedra, faces with six equivalent LaO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. All La–O bond lengths are 2.69 Å. Y3+ is bonded to twelve equivalent O2- atoms to form YO12 cuboctahedra that share corners with twelve equivalent LaO12 cuboctahedra, faces with six equivalent LaO12 cuboctahedra, and faces with eight equivalent AlO6 octahedra. All Y–O bond lengths are 2.66 Å. Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six equivalent AlO6 octahedra, a faceface with one YO12 cuboctahedra, and faces with seven LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There is three shorter (1.89 Å) and three longer (1.91 Å) Al–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted linear geometry to three La3+, one Y3+, and two equivalent Al3+ atoms. In the second O2- site, O2- is bonded in a distorted linear geometry to four La3+ and two equivalent Al3+ atoms.