SrCa7Cr2Mn6O21 crystallizes in the triclinic P1 space group. Sr(1) is bonded in a 10-coordinate geometry to one O(10), one O(14), one O(15), one O(18), one O(19), one O(2), one O(4), one O(7), one O(8), and one O(9) atom. There are seven inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to one O(10), one O(15), one O(18), one O(19), one O(3), one O(5), one O(6), one O(8), and one O(9) atom. In the second Ca site, Ca(2) is bonded in a 9-coordinate geometry to one O(10), one O(16), one O(17), one O(2), one O(20), one O(21), one O(7), one O(8), and one O(9) atom. In the third Ca site, Ca(3) is bonded in a 8-coordinate geometry to one O(10), one O(17), one O(21), one O(3), one O(5), one O(6), one O(8), and one O(9) atom. In the fourth Ca site, Ca(4) is bonded in a 9-coordinate geometry to one O(11), one O(12), one O(13), one O(14), one O(15), one O(18), one O(19), one O(2), and one O(4) atom. In the fifth Ca site, Ca(5) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(13), one O(15), one O(18), one O(19), one O(3), one O(5), and one O(6) atom. In the sixth Ca site, Ca(6) is bonded in a 9-coordinate geometry to one O(11), one O(12), one O(13), one O(16), one O(17), one O(2), one O(20), one O(21), and one O(4) atom. In the seventh Ca site, Ca(7) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(13), one O(17), one O(20), one O(21), one O(3), one O(5), and one O(6) atom. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(14), one O(16), and one O(7) atom to form CrO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid, and  a cornercorner with one Cr(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 39-42°. In the second Cr site, Cr(2) is bonded to one O(18), one O(20), one O(4), one O(5), and one O(7) atom to form CrO5 trigonal bipyramids that share corners with two equivalent Mn(4)O6 octahedra, corners with two equivalent Mn(5)O5 square pyramids, and  a cornercorner with one Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-27°. There are six inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(11), one O(15), one O(17), and one O(8) atom to form MnO5 square pyramids that share corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(4)O6 octahedra, and  a cornercorner with one Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 2-9°. In the second Mn site, Mn(2) is bonded to one O(12), one O(14), one O(16), one O(2), one O(3), and one O(9) atom to form distorted MnO6 octahedra that share corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(5)O5 square pyramids, and corners with two equivalent Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 3-12°. In the third Mn site, Mn(3) is bonded to one O(10), one O(13), one O(15), one O(17), one O(2), and one O(3) atom to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, and corners with two equivalent Mn(6)O5 square pyramids. The corner-sharing octahedral tilt angles range from 3-12°. In the fourth Mn site, Mn(4) is bonded to one O(11), one O(19), one O(21), one O(4), one O(5), and one O(8) atom to form MnO6 octahedra that share corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(6)O5 square pyramids, and corners with two equivalent Cr(2)O5 trigonal bipyramids. In the fifth Mn site, Mn(5) is bonded to one O(12), one O(18), one O(20), one O(6), and one O(9) atom to form MnO5 square pyramids that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(6)O5 square pyramid, and corners with two equivalent Cr(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 8-24°. In the sixth Mn site, Mn(6) is bonded to one O(10), one O(13), one O(19), one O(21), and one O(6) atom to form MnO5 square pyramids that share corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(4)O6 octahedra, and  a cornercorner with one Mn(5)O5 square pyramid. The corner-sharing octahedral tilt angles range from 1-14°. There are twenty-one inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ca(5), one Ca(7), one Cr(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Sr(1), one Ca(2), one Ca(4), one Ca(6), one Mn(2), and one Mn(3) atom. In the third O site, O(3) is bonded in a distorted linear geometry to one Ca(1), one Ca(3), one Ca(5), one Ca(7), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(4), one Ca(6), one Cr(2), and one Mn(4) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(3), one Ca(5), one Ca(7), one Cr(2), and one Mn(4) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(3), one Ca(5), one Ca(7), one Mn(5), and one Mn(6) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(2), one Cr(1), and one Cr(2) atom. In the eighth O site, O(8) is bonded to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(1), and one Mn(4) atom to form distorted OSrCa3Mn2 octahedra that share corners with two equivalent O(11)Ca4Mn2 octahedra, corners with two equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(10)SrCa3Mn2 octahedra,  a faceface with one O(15)SrCa3Mn2 octahedra, and  a faceface with one O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-63°. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(2), and one Mn(5) atom. In the tenth O site, O(10) is bonded to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(3), and one Mn(6) atom to form distorted OSrCa3Mn2 octahedra that share corners with two equivalent O(13)Ca4Mn2 octahedra, corners with two equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(8)SrCa3Mn2 octahedra,  a faceface with one O(15)SrCa3Mn2 octahedra, and  a faceface with one O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 5-62°. In the eleventh O site, O(11) is bonded to one Ca(4), one Ca(5), one Ca(6), one Ca(7), one Mn(1), and one Mn(4) atom to form distorted OCa4Mn2 octahedra that share corners with two equivalent O(8)SrCa3Mn2 octahedra, corners with two equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(13)Ca4Mn2 octahedra,  a faceface with one O(15)SrCa3Mn2 octahedra, and  a faceface with one O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-61°. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(6), one Mn(2), and one Mn(5) atom. In the thirteenth O site, O(13) is bonded to one Ca(4), one Ca(5), one Ca(6), one Ca(7), one Mn(3), and one Mn(6) atom to form distorted OCa4Mn2 octahedra that share corners with two equivalent O(10)SrCa3Mn2 octahedra, corners with two equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(11)Ca4Mn2 octahedra,  a faceface with one O(15)SrCa3Mn2 octahedra, and  a faceface with one O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 5-60°. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(4), one Cr(1), and one Mn(2) atom. In the fifteenth O site, O(15) is bonded to one Sr(1), one Ca(1), one Ca(4), one Ca(5), one Mn(1), and one Mn(3) atom to form distorted OSrCa3Mn2 octahedra that share corners with four equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(19)SrCa3Mn2 octahedra,  a faceface with one O(11)Ca4Mn2 octahedra,  a faceface with one O(13)Ca4Mn2 octahedra,  a faceface with one O(10)SrCa3Mn2 octahedra, and  a faceface with one O(8)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 4-17°. In the sixteenth O site, O(16) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(6), one Cr(1), and one Mn(2) atom. In the seventeenth O site, O(17) is bonded in a 6-coordinate geometry to one Ca(2), one Ca(3), one Ca(6), one Ca(7), one Mn(1), and one Mn(3) atom. In the eighteenth O site, O(18) is bonded to one Sr(1), one Ca(1), one Ca(4), one Ca(5), one Cr(2), and one Mn(5) atom to form distorted OSrCa3MnCr octahedra that share corners with two equivalent O(11)Ca4Mn2 octahedra, corners with two equivalent O(13)Ca4Mn2 octahedra, corners with two equivalent O(10)SrCa3Mn2 octahedra, corners with two equivalent O(8)SrCa3Mn2 octahedra, corners with four equivalent O(15)SrCa3Mn2 octahedra, and edges with two equivalent O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 4-63°. In the nineteenth O site, O(19) is bonded to one Sr(1), one Ca(1), one Ca(4), one Ca(5), one Mn(4), and one Mn(6) atom to form distorted OSrCa3Mn2 octahedra that share edges with two equivalent O(15)SrCa3Mn2 octahedra, edges with two equivalent O(18)SrCa3MnCr octahedra,  a faceface with one O(11)Ca4Mn2 octahedra,  a faceface with one O(13)Ca4Mn2 octahedra,  a faceface with one O(10)SrCa3Mn2 octahedra, and  a faceface with one O(8)SrCa3Mn2 octahedra. In the twentieth O site, O(20) is bonded in a 5-coordinate geometry to one Ca(2), one Ca(6), one Ca(7), one Cr(2), and one Mn(5) atom. In the twenty-first O site, O(21) is bonded in a 6-coordinate geometry to one Ca(2), one Ca(3), one Ca(6), one Ca(7), one Mn(4), and one Mn(6) atom.
SrCa7Cr2Mn6O21 crystallizes in the triclinic P1 space group. Sr(1) is bonded in a 10-coordinate geometry to one O(10), one O(14), one O(15), one O(18), one O(19), one O(2), one O(4), one O(7), one O(8), and one O(9) atom. The Sr(1)-O(10) bond length is 2.72 Å. The Sr(1)-O(14) bond length is 2.66 Å. The Sr(1)-O(15) bond length is 2.77 Å. The Sr(1)-O(18) bond length is 2.76 Å. The Sr(1)-O(19) bond length is 2.82 Å. The Sr(1)-O(2) bond length is 2.58 Å. The Sr(1)-O(4) bond length is 3.03 Å. The Sr(1)-O(7) bond length is 2.65 Å. The Sr(1)-O(8) bond length is 2.76 Å. The Sr(1)-O(9) bond length is 2.68 Å. There are seven inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 9-coordinate geometry to one O(10), one O(15), one O(18), one O(19), one O(3), one O(5), one O(6), one O(8), and one O(9) atom. The Ca(1)-O(10) bond length is 2.37 Å. The Ca(1)-O(15) bond length is 2.54 Å. The Ca(1)-O(18) bond length is 2.92 Å. The Ca(1)-O(19) bond length is 2.46 Å. The Ca(1)-O(3) bond length is 2.86 Å. The Ca(1)-O(5) bond length is 3.07 Å. The Ca(1)-O(6) bond length is 2.68 Å. The Ca(1)-O(8) bond length is 2.63 Å. The Ca(1)-O(9) bond length is 3.07 Å. In the second Ca site, Ca(2) is bonded in a 9-coordinate geometry to one O(10), one O(16), one O(17), one O(2), one O(20), one O(21), one O(7), one O(8), and one O(9) atom. The Ca(2)-O(10) bond length is 2.66 Å. The Ca(2)-O(16) bond length is 2.60 Å. The Ca(2)-O(17) bond length is 2.54 Å. The Ca(2)-O(2) bond length is 2.48 Å. The Ca(2)-O(20) bond length is 2.79 Å. The Ca(2)-O(21) bond length is 2.66 Å. The Ca(2)-O(7) bond length is 2.50 Å. The Ca(2)-O(8) bond length is 2.87 Å. The Ca(2)-O(9) bond length is 2.48 Å. In the third Ca site, Ca(3) is bonded in a 8-coordinate geometry to one O(10), one O(17), one O(21), one O(3), one O(5), one O(6), one O(8), and one O(9) atom. The Ca(3)-O(10) bond length is 2.41 Å. The Ca(3)-O(17) bond length is 2.51 Å. The Ca(3)-O(21) bond length is 2.53 Å. The Ca(3)-O(3) bond length is 2.78 Å. The Ca(3)-O(5) bond length is 2.92 Å. The Ca(3)-O(6) bond length is 2.54 Å. The Ca(3)-O(8) bond length is 2.63 Å. The Ca(3)-O(9) bond length is 3.00 Å. In the fourth Ca site, Ca(4) is bonded in a 9-coordinate geometry to one O(11), one O(12), one O(13), one O(14), one O(15), one O(18), one O(19), one O(2), and one O(4) atom. The Ca(4)-O(11) bond length is 2.65 Å. The Ca(4)-O(12) bond length is 2.45 Å. The Ca(4)-O(13) bond length is 2.56 Å. The Ca(4)-O(14) bond length is 2.28 Å. The Ca(4)-O(15) bond length is 2.83 Å. The Ca(4)-O(18) bond length is 2.79 Å. The Ca(4)-O(19) bond length is 2.56 Å. The Ca(4)-O(2) bond length is 2.85 Å. The Ca(4)-O(4) bond length is 2.42 Å. In the fifth Ca site, Ca(5) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(13), one O(15), one O(18), one O(19), one O(3), one O(5), and one O(6) atom. The Ca(5)-O(1) bond length is 2.59 Å. The Ca(5)-O(11) bond length is 2.72 Å. The Ca(5)-O(13) bond length is 2.73 Å. The Ca(5)-O(15) bond length is 2.57 Å. The Ca(5)-O(18) bond length is 2.87 Å. The Ca(5)-O(19) bond length is 2.55 Å. The Ca(5)-O(3) bond length is 2.84 Å. The Ca(5)-O(5) bond length is 2.62 Å. The Ca(5)-O(6) bond length is 2.84 Å. In the sixth Ca site, Ca(6) is bonded in a 9-coordinate geometry to one O(11), one O(12), one O(13), one O(16), one O(17), one O(2), one O(20), one O(21), and one O(4) atom. The Ca(6)-O(11) bond length is 2.58 Å. The Ca(6)-O(12) bond length is 2.56 Å. The Ca(6)-O(13) bond length is 2.53 Å. The Ca(6)-O(16) bond length is 2.27 Å. The Ca(6)-O(17) bond length is 2.85 Å. The Ca(6)-O(2) bond length is 2.94 Å. The Ca(6)-O(20) bond length is 2.45 Å. The Ca(6)-O(21) bond length is 2.45 Å. The Ca(6)-O(4) bond length is 2.57 Å. In the seventh Ca site, Ca(7) is bonded in a 9-coordinate geometry to one O(1), one O(11), one O(13), one O(17), one O(20), one O(21), one O(3), one O(5), and one O(6) atom. The Ca(7)-O(1) bond length is 2.50 Å. The Ca(7)-O(11) bond length is 2.68 Å. The Ca(7)-O(13) bond length is 2.66 Å. The Ca(7)-O(17) bond length is 2.70 Å. The Ca(7)-O(20) bond length is 3.00 Å. The Ca(7)-O(21) bond length is 2.79 Å. The Ca(7)-O(3) bond length is 2.70 Å. The Ca(7)-O(5) bond length is 2.49 Å. The Ca(7)-O(6) bond length is 2.63 Å. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(14), one O(16), and one O(7) atom to form CrO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(1)O5 square pyramid, and  a cornercorner with one Cr(2)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 39-42°. The Cr(1)-O(1) bond length is 1.76 Å. The Cr(1)-O(14) bond length is 1.77 Å. The Cr(1)-O(16) bond length is 1.78 Å. The Cr(1)-O(7) bond length is 1.83 Å. In the second Cr site, Cr(2) is bonded to one O(18), one O(20), one O(4), one O(5), and one O(7) atom to form CrO5 trigonal bipyramids that share corners with two equivalent Mn(4)O6 octahedra, corners with two equivalent Mn(5)O5 square pyramids, and  a cornercorner with one Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 18-27°. The Cr(2)-O(18) bond length is 2.02 Å. The Cr(2)-O(20) bond length is 1.99 Å. The Cr(2)-O(4) bond length is 1.93 Å. The Cr(2)-O(5) bond length is 1.98 Å. The Cr(2)-O(7) bond length is 1.90 Å. There are six inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(11), one O(15), one O(17), and one O(8) atom to form MnO5 square pyramids that share corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(4)O6 octahedra, and  a cornercorner with one Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 2-9°. The Mn(1)-O(1) bond length is 2.06 Å. The Mn(1)-O(11) bond length is 1.91 Å. The Mn(1)-O(15) bond length is 1.95 Å. The Mn(1)-O(17) bond length is 1.94 Å. The Mn(1)-O(8) bond length is 1.95 Å. In the second Mn site, Mn(2) is bonded to one O(12), one O(14), one O(16), one O(2), one O(3), and one O(9) atom to form distorted MnO6 octahedra that share corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(5)O5 square pyramids, and corners with two equivalent Cr(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 3-12°. The Mn(2)-O(12) bond length is 1.98 Å. The Mn(2)-O(14) bond length is 2.47 Å. The Mn(2)-O(16) bond length is 2.31 Å. The Mn(2)-O(2) bond length is 1.91 Å. The Mn(2)-O(3) bond length is 1.95 Å. The Mn(2)-O(9) bond length is 2.05 Å. In the third Mn site, Mn(3) is bonded to one O(10), one O(13), one O(15), one O(17), one O(2), and one O(3) atom to form MnO6 octahedra that share corners with two equivalent Mn(2)O6 octahedra, corners with two equivalent Mn(1)O5 square pyramids, and corners with two equivalent Mn(6)O5 square pyramids. The corner-sharing octahedral tilt angles range from 3-12°. The Mn(3)-O(10) bond length is 2.03 Å. The Mn(3)-O(13) bond length is 1.97 Å. The Mn(3)-O(15) bond length is 1.97 Å. The Mn(3)-O(17) bond length is 1.97 Å. The Mn(3)-O(2) bond length is 1.89 Å. The Mn(3)-O(3) bond length is 2.00 Å. In the fourth Mn site, Mn(4) is bonded to one O(11), one O(19), one O(21), one O(4), one O(5), and one O(8) atom to form MnO6 octahedra that share corners with two equivalent Mn(1)O5 square pyramids, corners with two equivalent Mn(6)O5 square pyramids, and corners with two equivalent Cr(2)O5 trigonal bipyramids. The Mn(4)-O(11) bond length is 1.97 Å. The Mn(4)-O(19) bond length is 2.02 Å. The Mn(4)-O(21) bond length is 2.00 Å. The Mn(4)-O(4) bond length is 1.94 Å. The Mn(4)-O(5) bond length is 2.04 Å. The Mn(4)-O(8) bond length is 1.99 Å. In the fifth Mn site, Mn(5) is bonded to one O(12), one O(18), one O(20), one O(6), and one O(9) atom to form MnO5 square pyramids that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(6)O5 square pyramid, and corners with two equivalent Cr(2)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 8-24°. The Mn(5)-O(12) bond length is 1.91 Å. The Mn(5)-O(18) bond length is 1.95 Å. The Mn(5)-O(20) bond length is 1.92 Å. The Mn(5)-O(6) bond length is 1.90 Å. The Mn(5)-O(9) bond length is 1.95 Å. In the sixth Mn site, Mn(6) is bonded to one O(10), one O(13), one O(19), one O(21), and one O(6) atom to form MnO5 square pyramids that share corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(4)O6 octahedra, and  a cornercorner with one Mn(5)O5 square pyramid. The corner-sharing octahedral tilt angles range from 1-14°. The Mn(6)-O(10) bond length is 1.93 Å. The Mn(6)-O(13) bond length is 1.89 Å. The Mn(6)-O(19) bond length is 1.91 Å. The Mn(6)-O(21) bond length is 1.90 Å. The Mn(6)-O(6) bond length is 1.91 Å. There are twenty-one inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ca(5), one Ca(7), one Cr(1), and one Mn(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Sr(1), one Ca(2), one Ca(4), one Ca(6), one Mn(2), and one Mn(3) atom. In the third O site, O(3) is bonded in a distorted linear geometry to one Ca(1), one Ca(3), one Ca(5), one Ca(7), one Mn(2), and one Mn(3) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(4), one Ca(6), one Cr(2), and one Mn(4) atom. In the fifth O site, O(5) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(3), one Ca(5), one Ca(7), one Cr(2), and one Mn(4) atom. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to one Ca(1), one Ca(3), one Ca(5), one Ca(7), one Mn(5), and one Mn(6) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(2), one Cr(1), and one Cr(2) atom. In the eighth O site, O(8) is bonded to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(1), and one Mn(4) atom to form distorted OSrCa3Mn2 octahedra that share corners with two equivalent O(11)Ca4Mn2 octahedra, corners with two equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(10)SrCa3Mn2 octahedra,  a faceface with one O(15)SrCa3Mn2 octahedra, and  a faceface with one O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-63°. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(2), and one Mn(5) atom. In the tenth O site, O(10) is bonded to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(3), and one Mn(6) atom to form distorted OSrCa3Mn2 octahedra that share corners with two equivalent O(13)Ca4Mn2 octahedra, corners with two equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(8)SrCa3Mn2 octahedra,  a faceface with one O(15)SrCa3Mn2 octahedra, and  a faceface with one O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 5-62°. In the eleventh O site, O(11) is bonded to one Ca(4), one Ca(5), one Ca(6), one Ca(7), one Mn(1), and one Mn(4) atom to form distorted OCa4Mn2 octahedra that share corners with two equivalent O(8)SrCa3Mn2 octahedra, corners with two equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(13)Ca4Mn2 octahedra,  a faceface with one O(15)SrCa3Mn2 octahedra, and  a faceface with one O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-61°. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(6), one Mn(2), and one Mn(5) atom. In the thirteenth O site, O(13) is bonded to one Ca(4), one Ca(5), one Ca(6), one Ca(7), one Mn(3), and one Mn(6) atom to form distorted OCa4Mn2 octahedra that share corners with two equivalent O(10)SrCa3Mn2 octahedra, corners with two equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(11)Ca4Mn2 octahedra,  a faceface with one O(15)SrCa3Mn2 octahedra, and  a faceface with one O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 5-60°. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(4), one Cr(1), and one Mn(2) atom. In the fifteenth O site, O(15) is bonded to one Sr(1), one Ca(1), one Ca(4), one Ca(5), one Mn(1), and one Mn(3) atom to form distorted OSrCa3Mn2 octahedra that share corners with four equivalent O(18)SrCa3MnCr octahedra, edges with two equivalent O(19)SrCa3Mn2 octahedra,  a faceface with one O(11)Ca4Mn2 octahedra,  a faceface with one O(13)Ca4Mn2 octahedra,  a faceface with one O(10)SrCa3Mn2 octahedra, and  a faceface with one O(8)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 4-17°. In the sixteenth O site, O(16) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(6), one Cr(1), and one Mn(2) atom. In the seventeenth O site, O(17) is bonded in a 6-coordinate geometry to one Ca(2), one Ca(3), one Ca(6), one Ca(7), one Mn(1), and one Mn(3) atom. In the eighteenth O site, O(18) is bonded to one Sr(1), one Ca(1), one Ca(4), one Ca(5), one Cr(2), and one Mn(5) atom to form distorted OSrCa3MnCr octahedra that share corners with two equivalent O(11)Ca4Mn2 octahedra, corners with two equivalent O(13)Ca4Mn2 octahedra, corners with two equivalent O(10)SrCa3Mn2 octahedra, corners with two equivalent O(8)SrCa3Mn2 octahedra, corners with four equivalent O(15)SrCa3Mn2 octahedra, and edges with two equivalent O(19)SrCa3Mn2 octahedra. The corner-sharing octahedral tilt angles range from 4-63°. In the nineteenth O site, O(19) is bonded to one Sr(1), one Ca(1), one Ca(4), one Ca(5), one Mn(4), and one Mn(6) atom to form distorted OSrCa3Mn2 octahedra that share edges with two equivalent O(15)SrCa3Mn2 octahedra, edges with two equivalent O(18)SrCa3MnCr octahedra,  a faceface with one O(11)Ca4Mn2 octahedra,  a faceface with one O(13)Ca4Mn2 octahedra,  a faceface with one O(10)SrCa3Mn2 octahedra, and  a faceface with one O(8)SrCa3Mn2 octahedra. In the twentieth O site, O(20) is bonded in a 5-coordinate geometry to one Ca(2), one Ca(6), one Ca(7), one Cr(2), and one Mn(5) atom. In the twenty-first O site, O(21) is bonded in a 6-coordinate geometry to one Ca(2), one Ca(3), one Ca(6), one Ca(7), one Mn(4), and one Mn(6) atom.