CaMn2O4 crystallizes in the orthorhombic Pnma space group. Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(4), two equivalent O(2), and three equivalent O(3) atoms to form a mixture of corner and edge-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 49-58°. In the second Mn site, Mn(2) is bonded to one O(2), two equivalent O(4), and three equivalent O(1) atoms to form a mixture of corner and edge-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 49-58°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1) and three equivalent Mn(2) atoms to form a mixture of distorted corner and edge-sharing OCa2Mn3 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Ca(1), one Mn(2), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing OCa2Mn3 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Ca(1) and three equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing OCa2Mn3 square pyramids. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Ca(1), one Mn(1), and two equivalent Mn(2) atoms.
CaMn2O4 crystallizes in the orthorhombic Pnma space group. Ca(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Both Ca(1)-O(1) bond lengths are 2.40 Å. There is one shorter (2.51 Å) and one longer (2.55 Å) Ca(1)-O(2) bond length. Both Ca(1)-O(3) bond lengths are 2.40 Å. Both Ca(1)-O(4) bond lengths are 2.49 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(4), two equivalent O(2), and three equivalent O(3) atoms to form a mixture of corner and edge-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 49-58°. The Mn(1)-O(4) bond length is 1.97 Å. Both Mn(1)-O(2) bond lengths are 2.08 Å. There is one shorter (1.96 Å) and two longer (2.15 Å) Mn(1)-O(3) bond lengths. In the second Mn site, Mn(2) is bonded to one O(2), two equivalent O(4), and three equivalent O(1) atoms to form a mixture of corner and edge-sharing MnO6 octahedra. The corner-sharing octahedral tilt angles range from 49-58°. The Mn(2)-O(2) bond length is 1.96 Å. Both Mn(2)-O(4) bond lengths are 2.19 Å. There is one shorter (1.95 Å) and two longer (2.14 Å) Mn(2)-O(1) bond lengths. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1) and three equivalent Mn(2) atoms to form a mixture of distorted corner and edge-sharing OCa2Mn3 trigonal bipyramids. In the second O site, O(2) is bonded to two equivalent Ca(1), one Mn(2), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing OCa2Mn3 trigonal bipyramids. In the third O site, O(3) is bonded to two equivalent Ca(1) and three equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing OCa2Mn3 square pyramids. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Ca(1), one Mn(1), and two equivalent Mn(2) atoms.