SrCa7TiMn7O21 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 5-coordinate geometry to one O(10), one O(18), one O(19), one O(7), one O(8), and one O(9) atom. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one O(16), one O(17), one O(2), one O(20), one O(21), 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(5), one O(6), one O(7), one O(8), and one O(9) atom. In the fourth Ca site, Ca(4) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(13), one O(14), one O(15), one O(19), 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(12), 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 6-coordinate geometry to one O(11), one O(12), one O(13), one O(16), one O(20), and one O(21) atom. In the seventh Ca site, Ca(7) is bonded in a 7-coordinate geometry to one O(1), one O(11), one O(13), one O(17), one O(3), one O(5), and one O(6) atom. Ti(1) is bonded to one O(1), one O(14), one O(16), and one O(7) atom to form TiO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(4)O5 square pyramid, and  a cornercorner with one Mn(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 41-48°. There are seven 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 trigonal bipyramids that share corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(5)O6 octahedra, and  a cornercorner with one Ti(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 14-28°. 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 Ti(1)O4 tetrahedra, and corners with two equivalent Mn(6)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-22°. 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(7)O5 square pyramids, and corners with two equivalent Mn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-22°. In the fourth Mn site, Mn(4) is bonded to one O(18), one O(20), one O(4), one O(5), and one O(7) atom to form MnO5 square pyramids that share corners with two equivalent Mn(5)O6 octahedra,  a cornercorner with one Ti(1)O4 tetrahedra, and corners with two equivalent Mn(6)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 23-27°. In the fifth Mn site, Mn(5) 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 corner-sharing MnO6 octahedra. In the sixth Mn site, Mn(6) is bonded to one O(12), one O(18), one O(20), one O(6), and one O(9) atom to form MnO5 trigonal bipyramids that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(7)O5 square pyramid, and corners with two equivalent Mn(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 2-35°. In the seventh Mn site, Mn(7) 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(5)O6 octahedra, and  a cornercorner with one Mn(6)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 18-35°. There are twenty-one inequivalent O sites. In the first O site, O(1) is bonded to one Ca(5), one Ca(7), one Ti(1), and one Mn(1) atom to form distorted corner-sharing OCa2TiMn tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(2), one Mn(2), and one Mn(3) atom. In the third O site, O(3) is bonded in a distorted see-saw-like geometry to 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 Mn(4), and one Mn(5) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(3), one Ca(5), one Ca(7), one Mn(4), and one Mn(5) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Ca(3), one Ca(5), one Ca(7), one Mn(6), and one Mn(7) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(1), one Ca(3), one Ti(1), and one Mn(4) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Sr(1), one Ca(1), one Ca(3), one Mn(1), and one Mn(5) atom. In the ninth O site, O(9) is bonded to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(2), and one Mn(6) atom to form distorted face-sharing OSrCa3Mn2 octahedra. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(1), one Ca(1), one Ca(3), one Mn(3), and one Mn(7) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to one Ca(4), one Ca(6), one Ca(7), one Mn(1), and one Mn(5) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(5), one Ca(6), one Mn(2), and one Mn(6) atom. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Ca(4), one Ca(5), one Ca(6), one Ca(7), one Mn(3), and one Mn(7) atom. In the fourteenth O site, O(14) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Ca(4), one Ti(1), and one Mn(2) atom. In the fifteenth O site, O(15) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(4), one Ca(5), one Mn(1), and one Mn(3) atom. In the sixteenth O site, O(16) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(6), one Ti(1), and one Mn(2) atom. In the seventeenth O site, O(17) is bonded in a 5-coordinate geometry to one Ca(2), one Ca(3), 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(5), one Mn(4), and one Mn(6) atom to form distorted OSrCa2Mn2 trigonal pyramids that share  a cornercorner with one O(1)Ca2TiMn tetrahedra and  a faceface with one O(9)SrCa3Mn2 octahedra. In the nineteenth O site, O(19) is bonded in a 5-coordinate geometry to one Sr(1), one Ca(1), one Ca(4), one Ca(5), one Mn(5), and one Mn(7) atom. In the twentieth O site, O(20) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(6), one Mn(4), and one Mn(6) atom. In the twenty-first O site, O(21) is bonded in a 5-coordinate geometry to one Ca(2), one Ca(3), one Ca(6), one Mn(5), and one Mn(7) atom.
SrCa7TiMn7O21 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 2.73 Å. The Sr(1)-O(14) bond length is 2.52 Å. The Sr(1)-O(15) bond length is 2.86 Å. The Sr(1)-O(18) bond length is 3.23 Å. The Sr(1)-O(19) bond length is 3.11 Å. The Sr(1)-O(2) bond length is 2.50 Å. The Sr(1)-O(4) bond length is 2.60 Å. The Sr(1)-O(7) bond length is 3.17 Å. The Sr(1)-O(8) bond length is 2.58 Å. The Sr(1)-O(9) bond length is 2.80 Å. There are seven inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 5-coordinate geometry to one O(10), one O(18), one O(19), one O(7), one O(8), and one O(9) atom. The Ca(1)-O(10) bond length is 2.32 Å. The Ca(1)-O(18) bond length is 2.34 Å. The Ca(1)-O(19) bond length is 2.50 Å. The Ca(1)-O(7) bond length is 2.61 Å. The Ca(1)-O(8) bond length is 2.42 Å. The Ca(1)-O(9) bond length is 2.93 Å. In the second Ca site, Ca(2) is bonded in a 6-coordinate geometry to one O(16), one O(17), one O(2), one O(20), one O(21), and one O(9) atom. The Ca(2)-O(16) bond length is 2.52 Å. The Ca(2)-O(17) bond length is 2.75 Å. The Ca(2)-O(2) bond length is 2.34 Å. The Ca(2)-O(20) bond length is 2.51 Å. The Ca(2)-O(21) bond length is 2.35 Å. The Ca(2)-O(9) bond length is 2.57 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(5), one O(6), one O(7), one O(8), and one O(9) atom. The Ca(3)-O(10) bond length is 2.61 Å. The Ca(3)-O(17) bond length is 2.41 Å. The Ca(3)-O(21) bond length is 2.56 Å. The Ca(3)-O(5) bond length is 2.42 Å. The Ca(3)-O(6) bond length is 2.45 Å. The Ca(3)-O(7) bond length is 2.62 Å. The Ca(3)-O(8) bond length is 2.76 Å. The Ca(3)-O(9) bond length is 2.96 Å. In the fourth Ca site, Ca(4) is bonded in a 7-coordinate geometry to one O(11), one O(12), one O(13), one O(14), one O(15), one O(19), and one O(4) atom. The Ca(4)-O(11) bond length is 2.62 Å. The Ca(4)-O(12) bond length is 2.42 Å. The Ca(4)-O(13) bond length is 2.54 Å. The Ca(4)-O(14) bond length is 2.28 Å. The Ca(4)-O(15) bond length is 2.38 Å. The Ca(4)-O(19) bond length is 2.47 Å. The Ca(4)-O(4) bond length is 2.50 Å. In the fifth Ca site, Ca(5) is bonded in a 9-coordinate geometry to one O(1), one O(12), 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 2.37 Å. The Ca(5)-O(12) bond length is 3.07 Å. The Ca(5)-O(13) bond length is 2.93 Å. The Ca(5)-O(15) bond length is 2.51 Å. The Ca(5)-O(18) bond length is 2.41 Å. The Ca(5)-O(19) bond length is 2.37 Å. The Ca(5)-O(3) bond length is 2.38 Å. The Ca(5)-O(5) bond length is 3.05 Å. The Ca(5)-O(6) bond length is 2.77 Å. In the sixth Ca site, Ca(6) is bonded in a 6-coordinate geometry to one O(11), one O(12), one O(13), one O(16), one O(20), and one O(21) atom. The Ca(6)-O(11) bond length is 2.34 Å. The Ca(6)-O(12) bond length is 2.41 Å. The Ca(6)-O(13) bond length is 2.34 Å. The Ca(6)-O(16) bond length is 2.30 Å. The Ca(6)-O(20) bond length is 2.36 Å. The Ca(6)-O(21) bond length is 2.47 Å. In the seventh Ca site, Ca(7) is bonded in a 7-coordinate geometry to one O(1), one O(11), one O(13), one O(17), one O(3), one O(5), and one O(6) atom. The Ca(7)-O(1) bond length is 2.38 Å. The Ca(7)-O(11) bond length is 2.56 Å. The Ca(7)-O(13) bond length is 2.49 Å. The Ca(7)-O(17) bond length is 2.55 Å. The Ca(7)-O(3) bond length is 2.51 Å. The Ca(7)-O(5) bond length is 2.41 Å. The Ca(7)-O(6) bond length is 2.36 Å. Ti(1) is bonded to one O(1), one O(14), one O(16), and one O(7) atom to form TiO4 tetrahedra that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(4)O5 square pyramid, and  a cornercorner with one Mn(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 41-48°. The Ti(1)-O(1) bond length is 1.81 Å. The Ti(1)-O(14) bond length is 1.81 Å. The Ti(1)-O(16) bond length is 1.82 Å. The Ti(1)-O(7) bond length is 1.80 Å. There are seven 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 trigonal bipyramids that share corners with two equivalent Mn(3)O6 octahedra, corners with two equivalent Mn(5)O6 octahedra, and  a cornercorner with one Ti(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 14-28°. The Mn(1)-O(1) bond length is 2.13 Å. The Mn(1)-O(11) bond length is 1.97 Å. The Mn(1)-O(15) bond length is 1.95 Å. The Mn(1)-O(17) bond length is 1.95 Å. The Mn(1)-O(8) bond length is 1.98 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 Ti(1)O4 tetrahedra, and corners with two equivalent Mn(6)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-22°. The Mn(2)-O(12) bond length is 2.04 Å. The Mn(2)-O(14) bond length is 2.52 Å. The Mn(2)-O(16) bond length is 2.29 Å. The Mn(2)-O(2) bond length is 1.98 Å. The Mn(2)-O(3) bond length is 1.96 Å. The Mn(2)-O(9) bond length is 2.07 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(7)O5 square pyramids, and corners with two equivalent Mn(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 21-22°. The Mn(3)-O(10) bond length is 2.00 Å. The Mn(3)-O(13) bond length is 2.04 Å. The Mn(3)-O(15) bond length is 1.99 Å. The Mn(3)-O(17) bond length is 1.98 Å. The Mn(3)-O(2) bond length is 1.93 Å. The Mn(3)-O(3) bond length is 2.06 Å. In the fourth Mn site, Mn(4) is bonded to one O(18), one O(20), one O(4), one O(5), and one O(7) atom to form MnO5 square pyramids that share corners with two equivalent Mn(5)O6 octahedra,  a cornercorner with one Ti(1)O4 tetrahedra, and corners with two equivalent Mn(6)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 23-27°. The Mn(4)-O(18) bond length is 2.00 Å. The Mn(4)-O(20) bond length is 2.01 Å. The Mn(4)-O(4) bond length is 1.95 Å. The Mn(4)-O(5) bond length is 1.99 Å. The Mn(4)-O(7) bond length is 2.08 Å. In the fifth Mn site, Mn(5) 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 corner-sharing MnO6 octahedra. The Mn(5)-O(11) bond length is 1.99 Å. The Mn(5)-O(19) bond length is 2.09 Å. The Mn(5)-O(21) bond length is 2.13 Å. The Mn(5)-O(4) bond length is 2.01 Å. The Mn(5)-O(5) bond length is 2.03 Å. The Mn(5)-O(8) bond length is 2.03 Å. In the sixth Mn site, Mn(6) is bonded to one O(12), one O(18), one O(20), one O(6), and one O(9) atom to form MnO5 trigonal bipyramids that share corners with two equivalent Mn(2)O6 octahedra,  a cornercorner with one Mn(7)O5 square pyramid, and corners with two equivalent Mn(4)O5 square pyramids. The corner-sharing octahedral tilt angles range from 2-35°. The Mn(6)-O(12) bond length is 1.92 Å. The Mn(6)-O(18) bond length is 2.00 Å. The Mn(6)-O(20) bond length is 1.97 Å. The Mn(6)-O(6) bond length is 1.94 Å. The Mn(6)-O(9) bond length is 1.97 Å. In the seventh Mn site, Mn(7) 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(5)O6 octahedra, and  a cornercorner with one Mn(6)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 18-35°. The Mn(7)-O(10) bond length is 1.95 Å. The Mn(7)-O(13) bond length is 1.94 Å. The Mn(7)-O(19) bond length is 1.90 Å. The Mn(7)-O(21) bond length is 1.91 Å. The Mn(7)-O(6) bond length is 1.89 Å. There are twenty-one inequivalent O sites. In the first O site, O(1) is bonded to one Ca(5), one Ca(7), one Ti(1), and one Mn(1) atom to form distorted corner-sharing OCa2TiMn tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(2), one Mn(2), and one Mn(3) atom. In the third O site, O(3) is bonded in a distorted see-saw-like geometry to 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 Mn(4), and one Mn(5) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(3), one Ca(5), one Ca(7), one Mn(4), and one Mn(5) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Ca(3), one Ca(5), one Ca(7), one Mn(6), and one Mn(7) atom. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(1), one Ca(3), one Ti(1), and one Mn(4) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Sr(1), one Ca(1), one Ca(3), one Mn(1), and one Mn(5) atom. In the ninth O site, O(9) is bonded to one Sr(1), one Ca(1), one Ca(2), one Ca(3), one Mn(2), and one Mn(6) atom to form distorted face-sharing OSrCa3Mn2 octahedra. In the tenth O site, O(10) is bonded in a 5-coordinate geometry to one Sr(1), one Ca(1), one Ca(3), one Mn(3), and one Mn(7) atom. In the eleventh O site, O(11) is bonded in a 5-coordinate geometry to one Ca(4), one Ca(6), one Ca(7), one Mn(1), and one Mn(5) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to one Ca(4), one Ca(5), one Ca(6), one Mn(2), and one Mn(6) atom. In the thirteenth O site, O(13) is bonded in a 5-coordinate geometry to one Ca(4), one Ca(5), one Ca(6), one Ca(7), one Mn(3), and one Mn(7) atom. In the fourteenth O site, O(14) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Ca(4), one Ti(1), and one Mn(2) atom. In the fifteenth O site, O(15) is bonded in a 4-coordinate geometry to one Sr(1), one Ca(4), one Ca(5), one Mn(1), and one Mn(3) atom. In the sixteenth O site, O(16) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(6), one Ti(1), and one Mn(2) atom. In the seventeenth O site, O(17) is bonded in a 5-coordinate geometry to one Ca(2), one Ca(3), 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(5), one Mn(4), and one Mn(6) atom to form distorted OSrCa2Mn2 trigonal pyramids that share  a cornercorner with one O(1)Ca2TiMn tetrahedra and  a faceface with one O(9)SrCa3Mn2 octahedra. In the nineteenth O site, O(19) is bonded in a 5-coordinate geometry to one Sr(1), one Ca(1), one Ca(4), one Ca(5), one Mn(5), and one Mn(7) atom. In the twentieth O site, O(20) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(6), one Mn(4), and one Mn(6) atom. In the twenty-first O site, O(21) is bonded in a 5-coordinate geometry to one Ca(2), one Ca(3), one Ca(6), one Mn(5), and one Mn(7) atom.