Materials Data on LaPr3Al4O12 by Materials Project
Pr3LaAl4O12 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are three 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 PrO12 cuboctahedra, faces with two equivalent LaO12 cuboctahedra, faces with four equivalent PrO12 cuboctahedra, and faces with eight AlO6 octahedra. There are a spread of Pr–O bond distances ranging from 2.48–2.90 Å. In the second Pr3+ site, Pr3+ is bonded to twelve O2- atoms to form distorted PrO12 cuboctahedra that share corners with twelve PrO12 cuboctahedra, faces with two equivalent PrO12 cuboctahedra, faces with four 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 third Pr3+ site, Pr3+ is bonded to twelve O2- atoms to form distorted PrO12 cuboctahedra that share corners with four equivalent PrO12 cuboctahedra, corners with eight equivalent LaO12 cuboctahedra, faces with six PrO12 cuboctahedra, and faces with eight AlO6 octahedra. There are a spread of Pr–O bond distances ranging from 2.49–2.89 Å. La3+ is bonded to twelve O2- atoms to form distorted LaO12 cuboctahedra that share corners with four equivalent LaO12 cuboctahedra, corners with eight equivalent PrO12 cuboctahedra, faces with six PrO12 cuboctahedra, and faces with eight AlO6 octahedra. There are a spread of La–O bond distances ranging from 2.50–2.91 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 two equivalent LaO12 cuboctahedra, and faces with six PrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–16°. There is three shorter (1.91 Å) and three longer (1.92 Å) Al–O bond length. In the second Al3+ site, Al3+ is bonded to six O2- atoms to form AlO6 octahedra that share corners with six AlO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six PrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 2–16°. There are a spread of Al–O bond distances ranging from 1.90–1.92 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three Pr3+, one La3+, and two equivalent Al3+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to three Pr3+, one La3+, and two equivalent Al3+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to three Pr3+, one La3+, and two equivalent Al3+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to three Pr3+, one La3+, and two equivalent Al3+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four Pr3+ and two Al3+ atoms. In the sixth O2- site, O2- is bonded in a distorted linear geometry to two equivalent Pr3+, two equivalent La3+, and two Al3+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to three Pr3+, one La3+, and two equivalent Al3+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to three Pr3+, one La3+, and two equivalent Al3+ atoms.