SrCa7Mn8O22 crystallizes in the orthorhombic Cmmm space group. Sr(1) is bonded in a distorted q6 geometry to two equivalent O(2) and eight equivalent O(4) atoms. There are five inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent O(1), two equivalent O(3), and eight equivalent O(4) 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 four equivalent Mn(2)O6 octahedra, and faces with four equivalent Mn(1)O5 square pyramids. In the second Ca site, Ca(2) is bonded in a distorted q6 geometry to two equivalent O(2), four equivalent O(4), and four equivalent O(5) atoms. In the third Ca site, Ca(3) is bonded to two equivalent O(1), two equivalent O(3), four equivalent O(4), and four equivalent O(5) 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 four equivalent Mn(2)O6 octahedra, and faces with four equivalent Mn(1)O5 square pyramids. In the fourth Ca site, Ca(4) is bonded in a distorted q6 geometry to two equivalent O(2) and eight equivalent O(5) atoms. In the fifth Ca site, Ca(5) is bonded to two equivalent O(1), two equivalent O(3), and eight equivalent O(5) 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 four equivalent Mn(2)O6 octahedra, and faces with four equivalent Mn(1)O5 square pyramids. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), two equivalent O(4), and two equivalent O(5) atoms to form MnO5 square pyramids that share corners with four equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(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 8-11°. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), two equivalent O(4), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(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 octahedra are not tilted. There are five 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 Mn(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(2) 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(2) atoms to form distorted OCa4Mn2 octahedra that share corners with four equivalent O(3)Ca4Mn2 octahedra, corners with eight equivalent O(4)SrCa3Mn2 octahedra, and faces with four equivalent O(4)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the fourth O site, O(4) is bonded to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(1), and one Mn(2) atom to form distorted OSrCa3Mn2 octahedra that share corners with two equivalent O(3)Ca4Mn2 octahedra, corners with eight equivalent O(4)SrCa3Mn2 octahedra, edges with four equivalent O(4)SrCa3Mn2 octahedra,  a faceface with one O(3)Ca4Mn2 octahedra, and faces with two equivalent O(4)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-64°. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ca(2), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Mn(2) atom.
SrCa7Mn8O22 crystallizes in the orthorhombic Cmmm space group. Sr(1) is bonded in a distorted q6 geometry to two equivalent O(2) and eight equivalent O(4) atoms. Both Sr(1)-O(2) bond lengths are 2.74 Å. All Sr(1)-O(4) bond lengths are 2.65 Å. There are five inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to two equivalent O(1), two equivalent O(3), and eight equivalent O(4) 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 four equivalent Mn(2)O6 octahedra, and faces with four equivalent Mn(1)O5 square pyramids. Both Ca(1)-O(1) bond lengths are 2.74 Å. Both Ca(1)-O(3) bond lengths are 2.74 Å. All Ca(1)-O(4) bond lengths are 2.82 Å. In the second Ca site, Ca(2) is bonded in a distorted q6 geometry to two equivalent O(2), four equivalent O(4), and four equivalent O(5) atoms. Both Ca(2)-O(2) bond lengths are 2.72 Å. All Ca(2)-O(4) bond lengths are 2.61 Å. All Ca(2)-O(5) bond lengths are 2.61 Å. In the third Ca site, Ca(3) is bonded to two equivalent O(1), two equivalent O(3), four equivalent O(4), and four equivalent O(5) 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 four equivalent Mn(2)O6 octahedra, and faces with four equivalent Mn(1)O5 square pyramids. Both Ca(3)-O(1) bond lengths are 2.72 Å. Both Ca(3)-O(3) bond lengths are 2.72 Å. All Ca(3)-O(4) bond lengths are 2.78 Å. All Ca(3)-O(5) bond lengths are 2.84 Å. In the fourth Ca site, Ca(4) is bonded in a distorted q6 geometry to two equivalent O(2) and eight equivalent O(5) atoms. Both Ca(4)-O(2) bond lengths are 2.71 Å. All Ca(4)-O(5) bond lengths are 2.59 Å. In the fifth Ca site, Ca(5) is bonded to two equivalent O(1), two equivalent O(3), and eight equivalent O(5) 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 four equivalent Mn(2)O6 octahedra, and faces with four equivalent Mn(1)O5 square pyramids. Both Ca(5)-O(1) bond lengths are 2.71 Å. Both Ca(5)-O(3) bond lengths are 2.71 Å. All Ca(5)-O(5) bond lengths are 2.83 Å. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), two equivalent O(4), and two equivalent O(5) atoms to form MnO5 square pyramids that share corners with four equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(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 8-11°. The Mn(1)-O(1) bond length is 1.85 Å. Both Mn(1)-O(4) bond lengths are 1.91 Å. Both Mn(1)-O(5) bond lengths are 1.90 Å. In the second Mn site, Mn(2) is bonded to one O(2), one O(3), two equivalent O(4), and two equivalent O(5) atoms to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with four equivalent Mn(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 octahedra are not tilted. The Mn(2)-O(2) bond length is 1.87 Å. The Mn(2)-O(3) bond length is 1.95 Å. Both Mn(2)-O(4) bond lengths are 1.97 Å. Both Mn(2)-O(5) bond lengths are 1.96 Å. There are five 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 Mn(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(2) 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(2) atoms to form distorted OCa4Mn2 octahedra that share corners with four equivalent O(3)Ca4Mn2 octahedra, corners with eight equivalent O(4)SrCa3Mn2 octahedra, and faces with four equivalent O(4)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the fourth O site, O(4) is bonded to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(1), and one Mn(2) atom to form distorted OSrCa3Mn2 octahedra that share corners with two equivalent O(3)Ca4Mn2 octahedra, corners with eight equivalent O(4)SrCa3Mn2 octahedra, edges with four equivalent O(4)SrCa3Mn2 octahedra,  a faceface with one O(3)Ca4Mn2 octahedra, and faces with two equivalent O(4)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-64°. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ca(2), one Ca(3), one Ca(4), one Ca(5), one Mn(1), and one Mn(2) atom.