Materials Data on LaPr3Al4O12 by Materials Project

Abstract

Pr3LaAl4O12 crystallizes in the trigonal R32 space group. The structure is three-dimensional. there are two inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded to twelve O2- atoms to form distorted PrO12 cuboctahedra that share corners with twelve equivalent PrO12 cuboctahedra, faces with three equivalent PrO12 cuboctahedra, faces with three equivalent LaO12 cuboctahedra, and faces with eight AlO6 octahedra. There are a spread of Pr–O bond distances ranging from 2.48–2.91 Å. In the second Pr3+ site, Pr3+ is bonded to twelve O2- atoms to form distorted PrO12 cuboctahedra that share corners with six equivalent PrO12 cuboctahedra, corners with six equivalent LaO12 cuboctahedra, faces with six equivalent PrO12 cuboctahedra, and faces with eight AlO6 octahedra. There are a spread of Pr–O bond distances ranging from 2.48–2.91 Å. La3+ is bonded to twelve O2- atoms to form distorted LaO12 cuboctahedra that share corners with six equivalent PrO12 cuboctahedra, corners with six equivalent LaO12 cuboctahedra, faces with six equivalent PrO12 cuboctahedra, and faces with eight AlO6 octahedra. There are a spread of La–O bond distances ranging from 2.49–2.89 Å. There are two inequivalent Al3+ sites. In the first Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six AlO6 octahedra, faces with three equivalent LaO12 cuboctahedra, and faces with five PrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 12–13°. All Al–O bond lengths are 1.91 Å. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six AlO6 octahedra, a faceface with one LaO12 cuboctahedra, and faces with seven PrO12 cuboctahedra. The corner-sharing octahedral tilt angles are 13°. All Al–O bond lengths are 1.91 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three Pr3+, one La3+, and two Al3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Pr3+, two equivalent La3+, and two equivalent Al3+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to four Pr3+ and two equivalent Al3+ atoms.