CaMn3O6 crystallizes in the monoclinic Cm space group. Ca(1) is bonded in a 6-coordinate geometry to one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form MnO5 square pyramids that share corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 52-59°. In the second Mn site, Mn(2) is bonded to one O(2), one O(5), two equivalent O(4), and two equivalent O(6) atoms to form MnO6 octahedra that share corners with two equivalent Mn(1)O5 square pyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. In the third Mn site, Mn(3) is bonded to one O(1), one O(6), two equivalent O(3), and two equivalent O(5) atoms to form distorted MnO6 octahedra that share corners with four equivalent Mn(1)O5 square pyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mn(3) and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Mn(1) and two equivalent Mn(3) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1) and two equivalent Mn(2) atoms. In the fifth O site, O(5) is bonded to two equivalent Ca(1), one Mn(2), and two equivalent Mn(3) atoms to form OCa2Mn3 square pyramids that share corners with two equivalent O(6)CaMn3 tetrahedra, edges with two equivalent O(5)Ca2Mn3 square pyramids, and edges with two equivalent O(6)CaMn3 tetrahedra. In the sixth O site, O(6) is bonded to one Ca(1), one Mn(3), and two equivalent Mn(2) atoms to form distorted OCaMn3 tetrahedra that share corners with two equivalent O(5)Ca2Mn3 square pyramids, corners with two equivalent O(6)CaMn3 tetrahedra, and edges with two equivalent O(5)Ca2Mn3 square pyramids.
CaMn3O6 crystallizes in the monoclinic Cm space group. Ca(1) is bonded in a 6-coordinate geometry to one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms. The Ca(1)-O(4) bond length is 2.31 Å. The Ca(1)-O(6) bond length is 2.18 Å. Both Ca(1)-O(2) bond lengths are 2.55 Å. Both Ca(1)-O(5) bond lengths are 2.29 Å. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(3), two equivalent O(1), and two equivalent O(2) atoms to form MnO5 square pyramids that share corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 52-59°. The Mn(1)-O(3) bond length is 2.09 Å. Both Mn(1)-O(1) bond lengths are 1.95 Å. Both Mn(1)-O(2) bond lengths are 2.07 Å. In the second Mn site, Mn(2) is bonded to one O(2), one O(5), two equivalent O(4), and two equivalent O(6) atoms to form MnO6 octahedra that share corners with two equivalent Mn(1)O5 square pyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. The Mn(2)-O(2) bond length is 2.04 Å. The Mn(2)-O(5) bond length is 2.01 Å. Both Mn(2)-O(4) bond lengths are 1.93 Å. Both Mn(2)-O(6) bond lengths are 1.95 Å. In the third Mn site, Mn(3) is bonded to one O(1), one O(6), two equivalent O(3), and two equivalent O(5) atoms to form distorted MnO6 octahedra that share corners with four equivalent Mn(1)O5 square pyramids, edges with two equivalent Mn(2)O6 octahedra, and edges with two equivalent Mn(3)O6 octahedra. The Mn(3)-O(1) bond length is 2.23 Å. The Mn(3)-O(6) bond length is 2.20 Å. Both Mn(3)-O(3) bond lengths are 1.92 Å. Both Mn(3)-O(5) bond lengths are 2.09 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Mn(3) and two equivalent Mn(1) atoms. In the second O site, O(2) is bonded in a 5-coordinate geometry to two equivalent Ca(1), one Mn(2), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded in a trigonal planar geometry to one Mn(1) and two equivalent Mn(3) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1) and two equivalent Mn(2) atoms. In the fifth O site, O(5) is bonded to two equivalent Ca(1), one Mn(2), and two equivalent Mn(3) atoms to form OCa2Mn3 square pyramids that share corners with two equivalent O(6)CaMn3 tetrahedra, edges with two equivalent O(5)Ca2Mn3 square pyramids, and edges with two equivalent O(6)CaMn3 tetrahedra. In the sixth O site, O(6) is bonded to one Ca(1), one Mn(3), and two equivalent Mn(2) atoms to form distorted OCaMn3 tetrahedra that share corners with two equivalent O(5)Ca2Mn3 square pyramids, corners with two equivalent O(6)CaMn3 tetrahedra, and edges with two equivalent O(5)Ca2Mn3 square pyramids.