Ca6Mn3Al2O15 crystallizes in the monoclinic Cc space group. There are six inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(13), one O(14), one O(2), one O(4), one O(5), and one O(6) atom. In the second Ca site, Ca(2) is bonded in a 5-coordinate geometry to one O(11), one O(14), one O(15), one O(3), one O(5), and one O(6) atom. In the third Ca site, Ca(3) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(12), one O(13), one O(15), one O(4), and one O(6) atom. In the fourth Ca site, Ca(4) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(13), one O(15), one O(2), one O(7), one O(8), and one O(9) atom. In the fifth Ca site, Ca(5) is bonded in a 5-coordinate geometry to one O(10), one O(11), one O(13), one O(14), one O(3), one O(7), and one O(8) atom. In the sixth Ca site, Ca(6) is bonded in a 7-coordinate geometry to one O(1), one O(11), one O(12), one O(14), one O(15), one O(8), and one O(9) atom. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(10), one O(12), one O(13), one O(15), one O(4), and one O(7) atom to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra,  a cornercorner with one Al(1)O4 tetrahedra, and  a cornercorner with one Al(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 10-22°. In the second Mn site, Mn(2) is bonded to one O(10), one O(11), one O(13), one O(14), one O(5), and one O(8) atom to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, and  a cornercorner with one Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 10-21°. In the third Mn site, Mn(3) is bonded to one O(11), one O(12), one O(14), one O(15), one O(6), and one O(9) atom to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, and  a cornercorner with one Al(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 14-22°. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), one O(5), and one O(7) atom to form AlO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra, and  a cornercorner with one Al(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-44°. In the second Al site, Al(2) is bonded to one O(1), one O(3), one O(4), and one O(9) atom to form AlO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra, and  a cornercorner with one Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 38-45°. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded to one Ca(3), one Ca(6), one Al(1), and one Al(2) atom to form corner-sharing OCa2Al2 tetrahedra. The corner-sharing octahedral tilt angles are 55°. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Ca(4), and one Al(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(2), one Ca(5), and one Al(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Ca(3), one Mn(1), and one Al(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Mn(2), and one Al(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), and one Mn(3) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(5), one Mn(1), and one Al(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(5), one Ca(6), and one Mn(2) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(6), one Mn(3), and one Al(2) atom. In the tenth O site, O(10) is bonded to one Ca(1), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Mn(2) atom to form distorted corner-sharing OCa4Mn2 octahedra. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(2), one Ca(5), one Ca(6), one Mn(2), and one Mn(3) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Ca(3), one Ca(4), one Ca(6), one Mn(1), and one Mn(3) atom. In the thirteenth O site, O(13) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Mn(2) atom. In the fourteenth O site, O(14) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(2), one Ca(5), one Ca(6), one Mn(2), and one Mn(3) atom. In the fifteenth O site, O(15) is bonded in a 6-coordinate geometry to one Ca(2), one Ca(3), one Ca(4), one Ca(6), one Mn(1), and one Mn(3) atom.
Ca6Mn3Al2O15 crystallizes in the monoclinic Cc space group. There are six inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 8-coordinate geometry to one O(10), one O(11), one O(13), one O(14), one O(2), one O(4), one O(5), and one O(6) atom. The Ca(1)-O(10) bond length is 2.64 Å. The Ca(1)-O(11) bond length is 2.63 Å. The Ca(1)-O(13) bond length is 2.54 Å. The Ca(1)-O(14) bond length is 2.43 Å. The Ca(1)-O(2) bond length is 2.16 Å. The Ca(1)-O(4) bond length is 2.75 Å. The Ca(1)-O(5) bond length is 2.31 Å. The Ca(1)-O(6) bond length is 2.69 Å. In the second Ca site, Ca(2) is bonded in a 5-coordinate geometry to one O(11), one O(14), one O(15), one O(3), one O(5), and one O(6) atom. The Ca(2)-O(11) bond length is 2.80 Å. The Ca(2)-O(14) bond length is 2.40 Å. The Ca(2)-O(15) bond length is 2.52 Å. The Ca(2)-O(3) bond length is 2.16 Å. The Ca(2)-O(5) bond length is 2.49 Å. The Ca(2)-O(6) bond length is 2.39 Å. In the third Ca site, Ca(3) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(12), one O(13), one O(15), one O(4), and one O(6) atom. The Ca(3)-O(1) bond length is 2.29 Å. The Ca(3)-O(10) bond length is 2.63 Å. The Ca(3)-O(12) bond length is 2.62 Å. The Ca(3)-O(13) bond length is 2.49 Å. The Ca(3)-O(15) bond length is 2.45 Å. The Ca(3)-O(4) bond length is 2.33 Å. The Ca(3)-O(6) bond length is 2.44 Å. In the fourth Ca site, Ca(4) is bonded in a 8-coordinate geometry to one O(10), one O(12), one O(13), one O(15), one O(2), one O(7), one O(8), and one O(9) atom. The Ca(4)-O(10) bond length is 2.50 Å. The Ca(4)-O(12) bond length is 2.50 Å. The Ca(4)-O(13) bond length is 2.69 Å. The Ca(4)-O(15) bond length is 2.72 Å. The Ca(4)-O(2) bond length is 2.15 Å. The Ca(4)-O(7) bond length is 2.33 Å. The Ca(4)-O(8) bond length is 2.58 Å. The Ca(4)-O(9) bond length is 2.61 Å. In the fifth Ca site, Ca(5) is bonded in a 5-coordinate geometry to one O(10), one O(11), one O(13), one O(14), one O(3), one O(7), and one O(8) atom. The Ca(5)-O(10) bond length is 2.44 Å. The Ca(5)-O(11) bond length is 2.44 Å. The Ca(5)-O(13) bond length is 2.87 Å. The Ca(5)-O(14) bond length is 2.84 Å. The Ca(5)-O(3) bond length is 2.16 Å. The Ca(5)-O(7) bond length is 2.48 Å. The Ca(5)-O(8) bond length is 2.41 Å. In the sixth Ca site, Ca(6) is bonded in a 7-coordinate geometry to one O(1), one O(11), one O(12), one O(14), one O(15), one O(8), and one O(9) atom. The Ca(6)-O(1) bond length is 2.31 Å. The Ca(6)-O(11) bond length is 2.37 Å. The Ca(6)-O(12) bond length is 2.55 Å. The Ca(6)-O(14) bond length is 2.53 Å. The Ca(6)-O(15) bond length is 2.63 Å. The Ca(6)-O(8) bond length is 2.57 Å. The Ca(6)-O(9) bond length is 2.30 Å. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(10), one O(12), one O(13), one O(15), one O(4), and one O(7) atom to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra,  a cornercorner with one Al(1)O4 tetrahedra, and  a cornercorner with one Al(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 10-22°. The Mn(1)-O(10) bond length is 1.96 Å. The Mn(1)-O(12) bond length is 1.94 Å. The Mn(1)-O(13) bond length is 1.96 Å. The Mn(1)-O(15) bond length is 1.94 Å. The Mn(1)-O(4) bond length is 2.01 Å. The Mn(1)-O(7) bond length is 2.08 Å. In the second Mn site, Mn(2) is bonded to one O(10), one O(11), one O(13), one O(14), one O(5), and one O(8) atom to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(3)O6 octahedra, and  a cornercorner with one Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 10-21°. The Mn(2)-O(10) bond length is 1.98 Å. The Mn(2)-O(11) bond length is 2.04 Å. The Mn(2)-O(13) bond length is 1.92 Å. The Mn(2)-O(14) bond length is 1.94 Å. The Mn(2)-O(5) bond length is 2.15 Å. The Mn(2)-O(8) bond length is 1.82 Å. In the third Mn site, Mn(3) is bonded to one O(11), one O(12), one O(14), one O(15), one O(6), and one O(9) atom to form MnO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, and  a cornercorner with one Al(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 14-22°. The Mn(3)-O(11) bond length is 1.94 Å. The Mn(3)-O(12) bond length is 1.93 Å. The Mn(3)-O(14) bond length is 2.01 Å. The Mn(3)-O(15) bond length is 2.04 Å. The Mn(3)-O(6) bond length is 1.82 Å. The Mn(3)-O(9) bond length is 2.09 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(1), one O(2), one O(5), and one O(7) atom to form AlO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(2)O6 octahedra, and  a cornercorner with one Al(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 39-44°. The Al(1)-O(1) bond length is 1.82 Å. The Al(1)-O(2) bond length is 1.72 Å. The Al(1)-O(5) bond length is 1.80 Å. The Al(1)-O(7) bond length is 1.83 Å. In the second Al site, Al(2) is bonded to one O(1), one O(3), one O(4), and one O(9) atom to form AlO4 tetrahedra that share  a cornercorner with one Mn(1)O6 octahedra,  a cornercorner with one Mn(3)O6 octahedra, and  a cornercorner with one Al(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 38-45°. The Al(2)-O(1) bond length is 1.83 Å. The Al(2)-O(3) bond length is 1.74 Å. The Al(2)-O(4) bond length is 1.83 Å. The Al(2)-O(9) bond length is 1.79 Å. There are fifteen inequivalent O sites. In the first O site, O(1) is bonded to one Ca(3), one Ca(6), one Al(1), and one Al(2) atom to form corner-sharing OCa2Al2 tetrahedra. The corner-sharing octahedral tilt angles are 55°. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Ca(4), and one Al(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(2), one Ca(5), and one Al(2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Ca(3), one Mn(1), and one Al(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Mn(2), and one Al(1) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), and one Mn(3) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(5), one Mn(1), and one Al(1) atom. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(5), one Ca(6), and one Mn(2) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(6), one Mn(3), and one Al(2) atom. In the tenth O site, O(10) is bonded to one Ca(1), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Mn(2) atom to form distorted corner-sharing OCa4Mn2 octahedra. In the eleventh O site, O(11) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(2), one Ca(5), one Ca(6), one Mn(2), and one Mn(3) atom. In the twelfth O site, O(12) is bonded in a 2-coordinate geometry to one Ca(3), one Ca(4), one Ca(6), one Mn(1), and one Mn(3) atom. In the thirteenth O site, O(13) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Mn(2) atom. In the fourteenth O site, O(14) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(2), one Ca(5), one Ca(6), one Mn(2), and one Mn(3) atom. In the fifteenth O site, O(15) is bonded in a 6-coordinate geometry to one Ca(2), one Ca(3), one Ca(4), one Ca(6), one Mn(1), and one Mn(3) atom.