DOE OSTI2020
Sr3LaMn4O12 crystallizes in the monoclinic P2 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 distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with two equivalent SrO12 cuboctahedra, faces with four equivalent LaO12 cuboctahedra, and faces with eight MnO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.55–2.98 Å. In the second Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with twelve SrO12 cuboctahedra, faces with two equivalent LaO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight MnO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.55–2.99 Å. In the third Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form distorted SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, corners with eight equivalent LaO12 cuboctahedra, faces with six SrO12 cuboctahedra, and faces with eight MnO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.55–3.05 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 SrO12 cuboctahedra, faces with six SrO12 cuboctahedra, and faces with eight MnO6 octahedra. There are a spread of La–O bond distances ranging from 2.50–3.01 Å. There are two inequivalent Mn+3.75+ sites. In the first Mn+3.75+ site, Mn+3.75+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six MnO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 11–17°. There are a spread of Mn–O bond distances ranging from 1.95–1.99 Å. In the second Mn+3.75+ site, Mn+3.75+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six MnO6 octahedra, faces with two equivalent LaO12 cuboctahedra, and faces with six SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 11–17°. There are a spread of Mn–O bond distances ranging from 1.95–1.98 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, and two Mn+3.75+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, and two Mn+3.75+ atoms. In the third O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+ and two equivalent Mn+3.75+ atoms. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, two equivalent La3+, and two equivalent Mn+3.75+ atoms. In the fifth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, and two Mn+3.75+ atoms. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to three Sr2+, one La3+, and two Mn+3.75+ atoms. In the seventh O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, two equivalent La3+, and two equivalent Mn+3.75+ atoms. In the eighth O2- site, O2- is bonded in a 2-coordinate geometry to four Sr2+ and two equivalent Mn+3.75+ atoms.