DOI: 10.17188/1293760
title: Materials Data on MgMn2O4 by Materials Project

description: MgMn2O4 crystallizes in the monoclinic C2 space group. The structure is three-dimensional. there are three inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four MgO6 octahedra, corners with four MnO5 trigonal bipyramids, and edges with two MnO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 44°. There are a spread of Mg–O bond distances ranging from 2.07–2.20 Å. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, corners with two equivalent MnO5 trigonal bipyramids, and edges with two equivalent MnO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 44°. There are two shorter (2.12 Å) and four longer (2.13 Å) Mg–O bond lengths. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with four equivalent MgO6 octahedra, corners with two equivalent MnO5 trigonal bipyramids, and edges with two equivalent MnO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 44°. There are four shorter (2.12 Å) and two longer (2.13 Å) Mg–O bond lengths. There are four inequivalent Mn3+ sites. In the first Mn3+ site, Mn3+ is bonded to five O2- atoms to form distorted MnO5 trigonal bipyramids that share corners with three MgO6 octahedra, edges with two MgO6 octahedra, and edges with two equivalent MnO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 51–76°. There are a spread of Mn–O bond distances ranging from 1.93–2.14 Å. In the second Mn3+ site, Mn3+ is bonded to five O2- atoms to form distorted MnO5 trigonal bipyramids that share corners with three MgO6 octahedra, edges with two MgO6 octahedra, and edges with two equivalent MnO5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 51–76°. There are a spread of Mn–O bond distances ranging from 1.93–2.14 Å. In the third Mn3+ site, Mn3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Mn–O bond distances ranging from 1.95–2.16 Å. In the fourth Mn3+ site, Mn3+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Mn–O bond distances ranging from 1.95–2.16 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Mn2 trigonal pyramids. In the second O2- site, O2- is bonded to two Mg2+ and two Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMg2Mn2 trigonal pyramids. In the third O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMgMn3 trigonal pyramids. In the fourth O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMgMn3 trigonal pyramids. In the fifth O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMgMn3 trigonal pyramids. In the sixth O2- site, O2- is bonded to two Mg2+ and two equivalent Mn3+ atoms to form distorted OMg2Mn2 trigonal pyramids that share corners with twelve OMg2Mn2 trigonal pyramids and edges with three OMgMn3 trigonal pyramids. In the seventh O2- site, O2- is bonded to two Mg2+ and two equivalent Mn3+ atoms to form distorted OMg2Mn2 trigonal pyramids that share corners with twelve OMg2Mn2 trigonal pyramids and edges with three OMgMn3 trigonal pyramids. In the eighth O2- site, O2- is bonded to one Mg2+ and three Mn3+ atoms to form a mixture of distorted edge and corner-sharing OMgMn3 trigonal pyramids.