SrCa7Mn6Al2O23 crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded in a distorted q6 geometry to one O(4), two equivalent O(2), four equivalent O(6), and four equivalent O(7) atoms. There are five inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(5), two equivalent O(3), four equivalent O(6), and four equivalent O(7) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(5)O12 cuboctahedra, faces with four equivalent Ca(3)O12 cuboctahedra, faces with two equivalent Mn(2)O6 octahedra, faces with four equivalent Mn(1)O6 octahedra, and faces with two equivalent Al(1)O5 square pyramids. In the second Ca site, Ca(2) is bonded in a distorted q6 geometry to one O(4), two equivalent O(2), two equivalent O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms. In the third Ca site, Ca(3) is bonded to one O(1), one O(5), two equivalent O(3), two equivalent O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(3)O12 cuboctahedra, faces with two equivalent Ca(1)O12 cuboctahedra, faces with two equivalent Ca(5)O12 cuboctahedra, faces with two equivalent Mn(2)O6 octahedra, faces with four equivalent Mn(1)O6 octahedra, and faces with two equivalent Al(1)O5 square pyramids. In the fourth Ca site, Ca(4) is bonded in a distorted q6 geometry to one O(4), two equivalent O(2), four equivalent O(8), and four equivalent O(9) atoms. In the fifth Ca site, Ca(5) is bonded to one O(1), one O(5), two equivalent O(3), four equivalent O(8), and four equivalent O(9) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, faces with four equivalent Ca(3)O12 cuboctahedra, faces with two equivalent Mn(2)O6 octahedra, faces with four equivalent Mn(1)O6 octahedra, and faces with two equivalent Al(1)O5 square pyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(3), one O(6), one O(7), one O(8), 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, corners with two equivalent Al(1)O5 square pyramids,  a faceface with one Ca(1)O12 cuboctahedra,  a faceface with one Ca(5)O12 cuboctahedra, and faces with two equivalent Ca(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second Mn site, Mn(2) is bonded to one O(4), one O(5), two equivalent O(7), and two equivalent O(9) atoms to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra,  a faceface with one Ca(1)O12 cuboctahedra,  a faceface with one Ca(5)O12 cuboctahedra, and faces with two equivalent Ca(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-4°. Al(1) is bonded to one O(1), two equivalent O(6), and two equivalent O(8) atoms to form distorted AlO5 square pyramids that share corners with four equivalent Mn(1)O6 octahedra,  a cornercorner with one Al(1)O5 square pyramid,  a faceface with one Ca(1)O12 cuboctahedra,  a faceface with one Ca(5)O12 cuboctahedra, and faces with two equivalent Ca(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 14-17°. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ca(1), one Ca(5), two equivalent Ca(3), and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Sr(1), one Ca(4), two equivalent Ca(2), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded to one Ca(1), one Ca(5), two equivalent Ca(3), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing OCa4Mn2 octahedra. The corner-sharing octahedral tilt angles are 4°. In the fourth O site, O(4) is bonded to one Sr(1), one Ca(4), two equivalent Ca(2), and two equivalent Mn(2) atoms to form distorted corner-sharing OSrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the fifth O site, O(5) is bonded to one Ca(1), one Ca(5), two equivalent Ca(3), and two equivalent Mn(2) atoms to form distorted OCa4Mn2 octahedra that share corners with two equivalent O(4)SrCa3Mn2 octahedra and edges with four equivalent O(3)Ca4Mn2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(1), and one Al(1) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(1), and one Mn(2) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Al(1) atom. In the ninth O site, O(9) is bonded in a distorted linear geometry to one Ca(2), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Mn(2) atom.
SrCa7Mn6Al2O23 crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded in a distorted q6 geometry to one O(4), two equivalent O(2), four equivalent O(6), and four equivalent O(7) atoms. The Sr(1)-O(4) bond length is 2.67 Å. Both Sr(1)-O(2) bond lengths are 2.69 Å. All Sr(1)-O(6) bond lengths are 2.64 Å. All Sr(1)-O(7) bond lengths are 2.74 Å. There are five inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(5), two equivalent O(3), four equivalent O(6), and four equivalent O(7) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(5)O12 cuboctahedra, faces with four equivalent Ca(3)O12 cuboctahedra, faces with two equivalent Mn(2)O6 octahedra, faces with four equivalent Mn(1)O6 octahedra, and faces with two equivalent Al(1)O5 square pyramids. The Ca(1)-O(1) bond length is 2.79 Å. The Ca(1)-O(5) bond length is 2.59 Å. Both Ca(1)-O(3) bond lengths are 2.70 Å. All Ca(1)-O(6) bond lengths are 2.87 Å. All Ca(1)-O(7) bond lengths are 2.63 Å. In the second Ca site, Ca(2) is bonded in a distorted q6 geometry to one O(4), two equivalent O(2), two equivalent O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms. The Ca(2)-O(4) bond length is 2.59 Å. There is one shorter (2.64 Å) and one longer (2.71 Å) Ca(2)-O(2) bond length. Both Ca(2)-O(6) bond lengths are 2.61 Å. Both Ca(2)-O(7) bond lengths are 2.68 Å. Both Ca(2)-O(8) bond lengths are 2.62 Å. Both Ca(2)-O(9) bond lengths are 2.68 Å. In the third Ca site, Ca(3) is bonded to one O(1), one O(5), two equivalent O(3), two equivalent O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(3)O12 cuboctahedra, faces with two equivalent Ca(1)O12 cuboctahedra, faces with two equivalent Ca(5)O12 cuboctahedra, faces with two equivalent Mn(2)O6 octahedra, faces with four equivalent Mn(1)O6 octahedra, and faces with two equivalent Al(1)O5 square pyramids. The Ca(3)-O(1) bond length is 2.76 Å. The Ca(3)-O(5) bond length is 2.58 Å. There is one shorter (2.66 Å) and one longer (2.68 Å) Ca(3)-O(3) bond length. Both Ca(3)-O(6) bond lengths are 2.82 Å. Both Ca(3)-O(7) bond lengths are 2.60 Å. Both Ca(3)-O(8) bond lengths are 2.89 Å. Both Ca(3)-O(9) bond lengths are 2.63 Å. In the fourth Ca site, Ca(4) is bonded in a distorted q6 geometry to one O(4), two equivalent O(2), four equivalent O(8), and four equivalent O(9) atoms. The Ca(4)-O(4) bond length is 2.56 Å. Both Ca(4)-O(2) bond lengths are 2.65 Å. All Ca(4)-O(8) bond lengths are 2.59 Å. All Ca(4)-O(9) bond lengths are 2.68 Å. In the fifth Ca site, Ca(5) is bonded to one O(1), one O(5), two equivalent O(3), four equivalent O(8), and four equivalent O(9) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, faces with four equivalent Ca(3)O12 cuboctahedra, faces with two equivalent Mn(2)O6 octahedra, faces with four equivalent Mn(1)O6 octahedra, and faces with two equivalent Al(1)O5 square pyramids. The Ca(5)-O(1) bond length is 2.73 Å. The Ca(5)-O(5) bond length is 2.57 Å. Both Ca(5)-O(3) bond lengths are 2.65 Å. All Ca(5)-O(8) bond lengths are 2.87 Å. All Ca(5)-O(9) bond lengths are 2.62 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), one O(3), one O(6), one O(7), one O(8), 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, corners with two equivalent Al(1)O5 square pyramids,  a faceface with one Ca(1)O12 cuboctahedra,  a faceface with one Ca(5)O12 cuboctahedra, and faces with two equivalent Ca(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 1-4°. The Mn(1)-O(2) bond length is 1.89 Å. The Mn(1)-O(3) bond length is 1.96 Å. The Mn(1)-O(6) bond length is 1.96 Å. The Mn(1)-O(7) bond length is 1.89 Å. The Mn(1)-O(8) bond length is 1.95 Å. The Mn(1)-O(9) bond length is 1.88 Å. In the second Mn site, Mn(2) is bonded to one O(4), one O(5), two equivalent O(7), and two equivalent O(9) atoms to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra,  a faceface with one Ca(1)O12 cuboctahedra,  a faceface with one Ca(5)O12 cuboctahedra, and faces with two equivalent Ca(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-4°. The Mn(2)-O(4) bond length is 1.93 Å. The Mn(2)-O(5) bond length is 1.92 Å. Both Mn(2)-O(7) bond lengths are 1.90 Å. Both Mn(2)-O(9) bond lengths are 1.88 Å. Al(1) is bonded to one O(1), two equivalent O(6), and two equivalent O(8) atoms to form distorted AlO5 square pyramids that share corners with four equivalent Mn(1)O6 octahedra,  a cornercorner with one Al(1)O5 square pyramid,  a faceface with one Ca(1)O12 cuboctahedra,  a faceface with one Ca(5)O12 cuboctahedra, and faces with two equivalent Ca(3)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 14-17°. The Al(1)-O(1) bond length is 1.73 Å. Both Al(1)-O(6) bond lengths are 1.86 Å. Both Al(1)-O(8) bond lengths are 1.86 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ca(1), one Ca(5), two equivalent Ca(3), and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Sr(1), one Ca(4), two equivalent Ca(2), and two equivalent Mn(1) atoms. In the third O site, O(3) is bonded to one Ca(1), one Ca(5), two equivalent Ca(3), and two equivalent Mn(1) atoms to form a mixture of distorted corner and edge-sharing OCa4Mn2 octahedra. The corner-sharing octahedral tilt angles are 4°. In the fourth O site, O(4) is bonded to one Sr(1), one Ca(4), two equivalent Ca(2), and two equivalent Mn(2) atoms to form distorted corner-sharing OSrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the fifth O site, O(5) is bonded to one Ca(1), one Ca(5), two equivalent Ca(3), and two equivalent Mn(2) atoms to form distorted OCa4Mn2 octahedra that share corners with two equivalent O(4)SrCa3Mn2 octahedra and edges with four equivalent O(3)Ca4Mn2 octahedra. The corner-sharing octahedral tilt angles are 1°. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(1), and one Al(1) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(1), and one Mn(2) atom. In the eighth O site, O(8) is bonded in a 2-coordinate geometry to one Ca(2), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Al(1) atom. In the ninth O site, O(9) is bonded in a distorted linear geometry to one Ca(2), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Mn(2) atom.