LaSr2Mn2O7 crystallizes in the monoclinic C2 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), two equivalent O(7), and two equivalent O(8) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), two equivalent O(7), and two equivalent O(8) atoms. In the third Sr site, Sr(3) is bonded to two equivalent O(10), two equivalent O(5), two equivalent O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(3)O12 cuboctahedra, faces with four equivalent Sr(4)O12 cuboctahedra, faces with two equivalent Mn(1)O6 octahedra, faces with two equivalent Mn(2)O6 octahedra, faces with two equivalent Mn(3)O6 octahedra, and faces with two equivalent Mn(4)O6 octahedra. In the fourth Sr site, Sr(4) is bonded to two equivalent O(10), two equivalent O(5), two equivalent O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(4)O12 cuboctahedra, faces with four equivalent Sr(3)O12 cuboctahedra, faces with two equivalent Mn(1)O6 octahedra, faces with two equivalent Mn(2)O6 octahedra, faces with two equivalent Mn(3)O6 octahedra, and faces with two equivalent Mn(4)O6 octahedra. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(10), two equivalent O(3), two equivalent O(4), and two equivalent O(9) atoms. In the second La site, La(2) is bonded in a 9-coordinate geometry to one O(2), two equivalent O(10), two equivalent O(3), two equivalent O(4), and two equivalent O(9) atoms. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(6), two equivalent O(7), and two equivalent O(8) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(4)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, faces with two equivalent Sr(3)O12 cuboctahedra, and faces with two equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Mn site, Mn(2) is bonded to one O(3), one O(5), two equivalent O(10), and two equivalent O(9) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(3)O6 octahedra, corners with four equivalent Mn(4)O6 octahedra, faces with two equivalent Sr(3)O12 cuboctahedra, and faces with two equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the third Mn site, Mn(3) is bonded to one O(2), one O(5), two equivalent O(7), and two equivalent O(8) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, faces with two equivalent Sr(3)O12 cuboctahedra, and faces with two equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth Mn site, Mn(4) is bonded to one O(4), one O(6), two equivalent O(10), and two equivalent O(9) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with four equivalent Mn(2)O6 octahedra, faces with two equivalent Sr(3)O12 cuboctahedra, and faces with two equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. There are ten inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Sr(2), one La(1), and one Mn(1) atom to form distorted OSr4LaMn octahedra that share corners with four equivalent O(1)Sr4LaMn octahedra, corners with four equivalent O(7)Sr4Mn2 octahedra, corners with four equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(3)SrLa4Mn octahedra, edges with two equivalent O(4)SrLa4Mn octahedra, edges with four equivalent O(2)Sr4LaMn octahedra, faces with two equivalent O(7)Sr4Mn2 octahedra, and faces with two equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 15-51°. In the second O site, O(2) is bonded to two equivalent Sr(1), two equivalent Sr(2), one La(2), and one Mn(3) atom to form distorted OSr4LaMn octahedra that share corners with four equivalent O(2)Sr4LaMn octahedra, corners with four equivalent O(7)Sr4Mn2 octahedra, corners with four equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(3)SrLa4Mn octahedra, edges with two equivalent O(4)SrLa4Mn octahedra, edges with four equivalent O(1)Sr4LaMn octahedra, faces with two equivalent O(7)Sr4Mn2 octahedra, and faces with two equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 17-55°. In the third O site, O(3) is bonded to one Sr(1), two equivalent La(1), two equivalent La(2), and one Mn(2) atom to form distorted OSrLa4Mn octahedra that share corners with two equivalent O(7)Sr4Mn2 octahedra, corners with two equivalent O(8)Sr4Mn2 octahedra, corners with four equivalent O(3)SrLa4Mn octahedra, edges with two equivalent O(1)Sr4LaMn octahedra, edges with two equivalent O(2)Sr4LaMn octahedra, and edges with four equivalent O(4)SrLa4Mn octahedra. The corner-sharing octahedral tilt angles range from 11-50°. In the fourth O site, O(4) is bonded to one Sr(2), two equivalent La(1), two equivalent La(2), and one Mn(4) atom to form distorted OSrLa4Mn octahedra that share corners with two equivalent O(7)Sr4Mn2 octahedra, corners with two equivalent O(8)Sr4Mn2 octahedra, corners with four equivalent O(4)SrLa4Mn octahedra, edges with two equivalent O(1)Sr4LaMn octahedra, edges with two equivalent O(2)Sr4LaMn octahedra, and edges with four equivalent O(3)SrLa4Mn octahedra. The corner-sharing octahedral tilt angles range from 10-50°. In the fifth O site, O(5) is bonded in a distorted linear geometry to two equivalent Sr(3), two equivalent Sr(4), one Mn(2), and one Mn(3) atom. In the sixth O site, O(6) is bonded in a distorted linear geometry to two equivalent Sr(3), two equivalent Sr(4), one Mn(1), and one Mn(4) atom. In the seventh O site, O(7) is bonded to one Sr(1), one Sr(2), one Sr(3), one Sr(4), one Mn(1), and one Mn(3) atom to form distorted OSr4Mn2 octahedra that share  a cornercorner with one O(3)SrLa4Mn octahedra,  a cornercorner with one O(4)SrLa4Mn octahedra, corners with two equivalent O(1)Sr4LaMn octahedra, corners with two equivalent O(2)Sr4LaMn octahedra, corners with two equivalent O(7)Sr4Mn2 octahedra, edges with two equivalent O(7)Sr4Mn2 octahedra,  a faceface with one O(1)Sr4LaMn octahedra,  a faceface with one O(2)Sr4LaMn octahedra, and faces with four equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-55°. In the eighth O site, O(8) is bonded to one Sr(1), one Sr(2), one Sr(3), one Sr(4), one Mn(1), and one Mn(3) atom to form distorted OSr4Mn2 octahedra that share  a cornercorner with one O(3)SrLa4Mn octahedra,  a cornercorner with one O(4)SrLa4Mn octahedra, corners with two equivalent O(1)Sr4LaMn octahedra, corners with two equivalent O(2)Sr4LaMn octahedra, corners with two equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(8)Sr4Mn2 octahedra,  a faceface with one O(1)Sr4LaMn octahedra,  a faceface with one O(2)Sr4LaMn octahedra, and faces with four equivalent O(7)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-51°. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Sr(3), one Sr(4), one La(1), one La(2), one Mn(2), and one Mn(4) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Sr(3), one Sr(4), one La(1), one La(2), one Mn(2), and one Mn(4) atom.
LaSr2Mn2O7 crystallizes in the monoclinic C2 space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), two equivalent O(7), and two equivalent O(8) atoms. The Sr(1)-O(3) bond length is 2.45 Å. Both Sr(1)-O(1) bond lengths are 2.81 Å. Both Sr(1)-O(2) bond lengths are 2.82 Å. Both Sr(1)-O(7) bond lengths are 2.56 Å. Both Sr(1)-O(8) bond lengths are 2.61 Å. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), two equivalent O(7), and two equivalent O(8) atoms. The Sr(2)-O(4) bond length is 2.50 Å. Both Sr(2)-O(1) bond lengths are 2.82 Å. Both Sr(2)-O(2) bond lengths are 2.82 Å. Both Sr(2)-O(7) bond lengths are 2.56 Å. Both Sr(2)-O(8) bond lengths are 2.61 Å. In the third Sr site, Sr(3) is bonded to two equivalent O(10), two equivalent O(5), two equivalent O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(3)O12 cuboctahedra, faces with four equivalent Sr(4)O12 cuboctahedra, faces with two equivalent Mn(1)O6 octahedra, faces with two equivalent Mn(2)O6 octahedra, faces with two equivalent Mn(3)O6 octahedra, and faces with two equivalent Mn(4)O6 octahedra. Both Sr(3)-O(10) bond lengths are 2.95 Å. Both Sr(3)-O(5) bond lengths are 2.80 Å. Both Sr(3)-O(6) bond lengths are 2.79 Å. Both Sr(3)-O(7) bond lengths are 2.68 Å. Both Sr(3)-O(8) bond lengths are 2.74 Å. Both Sr(3)-O(9) bond lengths are 2.91 Å. In the fourth Sr site, Sr(4) is bonded to two equivalent O(10), two equivalent O(5), two equivalent O(6), two equivalent O(7), two equivalent O(8), and two equivalent O(9) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(4)O12 cuboctahedra, faces with four equivalent Sr(3)O12 cuboctahedra, faces with two equivalent Mn(1)O6 octahedra, faces with two equivalent Mn(2)O6 octahedra, faces with two equivalent Mn(3)O6 octahedra, and faces with two equivalent Mn(4)O6 octahedra. Both Sr(4)-O(10) bond lengths are 2.94 Å. Both Sr(4)-O(5) bond lengths are 2.79 Å. Both Sr(4)-O(6) bond lengths are 2.79 Å. Both Sr(4)-O(7) bond lengths are 2.68 Å. Both Sr(4)-O(8) bond lengths are 2.75 Å. Both Sr(4)-O(9) bond lengths are 2.90 Å. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(10), two equivalent O(3), two equivalent O(4), and two equivalent O(9) atoms. The La(1)-O(1) bond length is 2.37 Å. Both La(1)-O(10) bond lengths are 2.58 Å. Both La(1)-O(3) bond lengths are 2.80 Å. Both La(1)-O(4) bond lengths are 2.80 Å. Both La(1)-O(9) bond lengths are 2.51 Å. In the second La site, La(2) is bonded in a 9-coordinate geometry to one O(2), two equivalent O(10), two equivalent O(3), two equivalent O(4), and two equivalent O(9) atoms. The La(2)-O(2) bond length is 2.33 Å. Both La(2)-O(10) bond lengths are 2.58 Å. Both La(2)-O(3) bond lengths are 2.81 Å. Both La(2)-O(4) bond lengths are 2.80 Å. Both La(2)-O(9) bond lengths are 2.51 Å. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(6), two equivalent O(7), and two equivalent O(8) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(4)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, faces with two equivalent Sr(3)O12 cuboctahedra, and faces with two equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. The Mn(1)-O(1) bond length is 2.02 Å. The Mn(1)-O(6) bond length is 1.97 Å. Both Mn(1)-O(7) bond lengths are 1.89 Å. Both Mn(1)-O(8) bond lengths are 1.93 Å. In the second Mn site, Mn(2) is bonded to one O(3), one O(5), two equivalent O(10), and two equivalent O(9) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(3)O6 octahedra, corners with four equivalent Mn(4)O6 octahedra, faces with two equivalent Sr(3)O12 cuboctahedra, and faces with two equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. The Mn(2)-O(3) bond length is 2.00 Å. The Mn(2)-O(5) bond length is 1.89 Å. Both Mn(2)-O(10) bond lengths are 1.91 Å. Both Mn(2)-O(9) bond lengths are 1.90 Å. In the third Mn site, Mn(3) is bonded to one O(2), one O(5), two equivalent O(7), and two equivalent O(8) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, faces with two equivalent Sr(3)O12 cuboctahedra, and faces with two equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-1°. The Mn(3)-O(2) bond length is 2.06 Å. The Mn(3)-O(5) bond length is 2.03 Å. Both Mn(3)-O(7) bond lengths are 2.14 Å. Both Mn(3)-O(8) bond lengths are 1.94 Å. In the fourth Mn site, Mn(4) is bonded to one O(4), one O(6), two equivalent O(10), and two equivalent O(9) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with four equivalent Mn(2)O6 octahedra, faces with two equivalent Sr(3)O12 cuboctahedra, and faces with two equivalent Sr(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-8°. The Mn(4)-O(4) bond length is 1.99 Å. The Mn(4)-O(6) bond length is 1.91 Å. Both Mn(4)-O(10) bond lengths are 1.97 Å. Both Mn(4)-O(9) bond lengths are 2.13 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1), two equivalent Sr(2), one La(1), and one Mn(1) atom to form distorted OSr4LaMn octahedra that share corners with four equivalent O(1)Sr4LaMn octahedra, corners with four equivalent O(7)Sr4Mn2 octahedra, corners with four equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(3)SrLa4Mn octahedra, edges with two equivalent O(4)SrLa4Mn octahedra, edges with four equivalent O(2)Sr4LaMn octahedra, faces with two equivalent O(7)Sr4Mn2 octahedra, and faces with two equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 15-51°. In the second O site, O(2) is bonded to two equivalent Sr(1), two equivalent Sr(2), one La(2), and one Mn(3) atom to form distorted OSr4LaMn octahedra that share corners with four equivalent O(2)Sr4LaMn octahedra, corners with four equivalent O(7)Sr4Mn2 octahedra, corners with four equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(3)SrLa4Mn octahedra, edges with two equivalent O(4)SrLa4Mn octahedra, edges with four equivalent O(1)Sr4LaMn octahedra, faces with two equivalent O(7)Sr4Mn2 octahedra, and faces with two equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 17-55°. In the third O site, O(3) is bonded to one Sr(1), two equivalent La(1), two equivalent La(2), and one Mn(2) atom to form distorted OSrLa4Mn octahedra that share corners with two equivalent O(7)Sr4Mn2 octahedra, corners with two equivalent O(8)Sr4Mn2 octahedra, corners with four equivalent O(3)SrLa4Mn octahedra, edges with two equivalent O(1)Sr4LaMn octahedra, edges with two equivalent O(2)Sr4LaMn octahedra, and edges with four equivalent O(4)SrLa4Mn octahedra. The corner-sharing octahedral tilt angles range from 11-50°. In the fourth O site, O(4) is bonded to one Sr(2), two equivalent La(1), two equivalent La(2), and one Mn(4) atom to form distorted OSrLa4Mn octahedra that share corners with two equivalent O(7)Sr4Mn2 octahedra, corners with two equivalent O(8)Sr4Mn2 octahedra, corners with four equivalent O(4)SrLa4Mn octahedra, edges with two equivalent O(1)Sr4LaMn octahedra, edges with two equivalent O(2)Sr4LaMn octahedra, and edges with four equivalent O(3)SrLa4Mn octahedra. The corner-sharing octahedral tilt angles range from 10-50°. In the fifth O site, O(5) is bonded in a distorted linear geometry to two equivalent Sr(3), two equivalent Sr(4), one Mn(2), and one Mn(3) atom. In the sixth O site, O(6) is bonded in a distorted linear geometry to two equivalent Sr(3), two equivalent Sr(4), one Mn(1), and one Mn(4) atom. In the seventh O site, O(7) is bonded to one Sr(1), one Sr(2), one Sr(3), one Sr(4), one Mn(1), and one Mn(3) atom to form distorted OSr4Mn2 octahedra that share  a cornercorner with one O(3)SrLa4Mn octahedra,  a cornercorner with one O(4)SrLa4Mn octahedra, corners with two equivalent O(1)Sr4LaMn octahedra, corners with two equivalent O(2)Sr4LaMn octahedra, corners with two equivalent O(7)Sr4Mn2 octahedra, edges with two equivalent O(7)Sr4Mn2 octahedra,  a faceface with one O(1)Sr4LaMn octahedra,  a faceface with one O(2)Sr4LaMn octahedra, and faces with four equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-55°. In the eighth O site, O(8) is bonded to one Sr(1), one Sr(2), one Sr(3), one Sr(4), one Mn(1), and one Mn(3) atom to form distorted OSr4Mn2 octahedra that share  a cornercorner with one O(3)SrLa4Mn octahedra,  a cornercorner with one O(4)SrLa4Mn octahedra, corners with two equivalent O(1)Sr4LaMn octahedra, corners with two equivalent O(2)Sr4LaMn octahedra, corners with two equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(8)Sr4Mn2 octahedra,  a faceface with one O(1)Sr4LaMn octahedra,  a faceface with one O(2)Sr4LaMn octahedra, and faces with four equivalent O(7)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 1-51°. In the ninth O site, O(9) is bonded in a 6-coordinate geometry to one Sr(3), one Sr(4), one La(1), one La(2), one Mn(2), and one Mn(4) atom. In the tenth O site, O(10) is bonded in a 2-coordinate geometry to one Sr(3), one Sr(4), one La(1), one La(2), one Mn(2), and one Mn(4) atom.