CaMn4O8 is beta indium sulfide-derived structured and crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form edge-sharing MnO6 octahedra. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form edge-sharing MnO6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to one Ca(1), one Mn(1), and two equivalent Mn(2) atoms to form a mixture of distorted corner and edge-sharing OCaMn3 trigonal pyramids.
CaMn4O8 is beta indium sulfide-derived structured and crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. Both Ca(1)-O(1) bond lengths are 2.37 Å. Both Ca(1)-O(2) bond lengths are 2.39 Å. Both Ca(1)-O(4) bond lengths are 2.42 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form edge-sharing MnO6 octahedra. The Mn(1)-O(3) bond length is 2.05 Å. The Mn(1)-O(4) bond length is 2.04 Å. There is one shorter (1.92 Å) and one longer (2.25 Å) Mn(1)-O(1) bond length. There is one shorter (1.94 Å) and one longer (2.17 Å) Mn(1)-O(2) bond length. In the second Mn site, Mn(2) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form edge-sharing MnO6 octahedra. The Mn(2)-O(1) bond length is 1.93 Å. The Mn(2)-O(2) bond length is 1.93 Å. There is one shorter (1.93 Å) and one longer (1.94 Å) Mn(2)-O(3) bond length. There is one shorter (1.99 Å) and one longer (2.00 Å) Mn(2)-O(4) bond length. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Mn(2) atoms. In the fourth O site, O(4) is bonded to one Ca(1), one Mn(1), and two equivalent Mn(2) atoms to form a mixture of distorted corner and edge-sharing OCaMn3 trigonal pyramids.