Materials Data on Sr2LaMn2O7 by Materials Project
LaSr2Mn2O7 crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. there are two inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Sr–O bond distances ranging from 2.49–2.81 Å. In the second Sr2+ site, Sr2+ is bonded to twelve O2- atoms to form SrO12 cuboctahedra that share corners with four equivalent SrO12 cuboctahedra, faces with four equivalent SrO12 cuboctahedra, and faces with eight MnO6 octahedra. There are a spread of Sr–O bond distances ranging from 2.72–2.92 Å. La3+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of La–O bond distances ranging from 2.34–2.79 Å. There are two inequivalent Mn+3.50+ sites. In the first Mn+3.50+ site, Mn+3.50+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with five MnO6 octahedra and faces with four equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–1°. There are a spread of Mn–O bond distances ranging from 1.96–2.09 Å. In the second Mn+3.50+ site, Mn+3.50+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with five MnO6 octahedra and faces with four equivalent SrO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–8°. There are a spread of Mn–O bond distances ranging from 1.92–2.03 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Sr2+, one La3+, and one Mn+3.50+ atom to form distorted OSr4LaMn octahedra that share corners with twelve OSr4LaMn octahedra, edges with eight OSr4LaMn octahedra, and faces with four equivalent OSr4Mn2 octahedra. The corner-sharing octahedra tilt angles range from 17–51°. In the second O2- site, O2- is bonded to one Sr2+, four equivalent La3+, and one Mn+3.50+ atom to form distorted OSrLa4Mn octahedra that share corners with eight OSrLa4Mn octahedra and edges with eight OSr4LaMn octahedra. The corner-sharing octahedra tilt angles range from 11–49°. In the third O2- site, O2- is bonded to four Sr2+ and two equivalent Mn+3.50+ atoms to form distorted OSr4Mn2 octahedra that share corners with eight OSr4LaMn octahedra, edges with two equivalent OSr4Mn2 octahedra, and faces with six OSr4LaMn octahedra. The corner-sharing octahedra tilt angles range from 1–51°. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Sr2+, two equivalent La3+, and two equivalent Mn+3.50+ atoms. In the fifth O2- site, O2- is bonded in a distorted linear geometry to four equivalent Sr2+ and two Mn+3.50+ atoms.