Materials Data on LaMn7O12 by Materials Project
LaMn7O12 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. La3+ is bonded to twelve O2- atoms to form LaO12 cuboctahedra that share faces with eight MnO6 octahedra. There are a spread of La–O bond distances ranging from 2.66–2.74 Å. There are five inequivalent Mn3+ sites. In the first Mn3+ site, Mn3+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Mn–O bond lengths are 1.97 Å. In the second Mn3+ site, Mn3+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Mn–O bond lengths are 1.97 Å. In the third Mn3+ site, Mn3+ is bonded in a square co-planar geometry to four O2- atoms. There is two shorter (1.97 Å) and two longer (1.98 Å) Mn–O bond length. In the fourth Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six MnO6 octahedra and faces with two equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 42–43°. There are a spread of Mn–O bond distances ranging from 1.97–2.08 Å. In the fifth Mn3+ site, Mn3+ is bonded to six O2- atoms to form MnO6 octahedra that share corners with six MnO6 octahedra and faces with two equivalent LaO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 41–42°. There are a spread of Mn–O bond distances ranging from 1.99–2.10 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to one La3+ and three Mn3+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and three Mn3+ atoms. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one La3+ and three Mn3+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one La3+ and three Mn3+ atoms.