Sr6Mn3FeO14 crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent O(5), two equivalent O(6), four equivalent O(7), and four equivalent O(8) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Sr(2)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 Fe(1)O6 octahedra. In the second Sr site, Sr(2) is bonded to two equivalent O(5), two equivalent O(6), four equivalent O(7), and four equivalent O(8) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(2)O12 cuboctahedra, faces with four equivalent Sr(1)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 Fe(1)O6 octahedra. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), and four equivalent O(7) atoms. In the fourth Sr site, Sr(4) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and four equivalent O(7) atoms. In the fifth Sr site, Sr(5) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(3), two equivalent O(4), and four equivalent O(8) atoms. In the sixth Sr site, Sr(6) is bonded in a 9-coordinate geometry to one O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(8) atoms. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(6), and four equivalent O(7) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Mn site, Mn(2) is bonded to one O(4), one O(6), and four equivalent O(8) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the third Mn site, Mn(3) is bonded to one O(3), one O(5), and four equivalent O(8) atoms to form MnO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with four equivalent Mn(2)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. Fe(1) is bonded to one O(2), one O(5), and four equivalent O(7) atoms to form FeO6 octahedra that share  a cornercorner with one Mn(3)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Sr(5), two equivalent Sr(3), two equivalent Sr(4), and one Mn(1) atom to form distorted OSr5Mn octahedra that share corners with four equivalent O(8)Sr4Mn2 octahedra, corners with four equivalent O(1)Sr5Mn octahedra, corners with eight equivalent O(7)Sr4MnFe octahedra, edges with two equivalent O(3)Sr5Mn octahedra, edges with two equivalent O(4)Sr5Mn octahedra, edges with four equivalent O(2)Sr5Fe octahedra, and faces with four equivalent O(7)Sr4MnFe octahedra. The corner-sharing octahedral tilt angles range from 9-55°. In the second O site, O(2) is bonded to one Sr(6), two equivalent Sr(3), two equivalent Sr(4), and one Fe(1) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(5)Sr4MnFe octahedra, corners with four equivalent O(8)Sr4Mn2 octahedra, corners with four equivalent O(2)Sr5Fe octahedra, corners with eight equivalent O(7)Sr4MnFe octahedra, edges with two equivalent O(3)Sr5Mn octahedra, edges with two equivalent O(4)Sr5Mn octahedra, edges with four equivalent O(1)Sr5Mn octahedra, and faces with four equivalent O(7)Sr4MnFe octahedra. The corner-sharing octahedral tilt angles range from 0-55°. In the third O site, O(3) is bonded to one Sr(3), two equivalent Sr(5), two equivalent Sr(6), and one Mn(3) atom to form distorted OSr5Mn octahedra that share  a cornercorner with one O(5)Sr4MnFe octahedra, corners with four equivalent O(7)Sr4MnFe octahedra, corners with four equivalent O(3)Sr5Mn octahedra, corners with eight equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(2)Sr5Fe octahedra, edges with two equivalent O(1)Sr5Mn octahedra, edges with four equivalent O(4)Sr5Mn octahedra, and faces with four equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-55°. In the fourth O site, O(4) is bonded to one Sr(4), two equivalent Sr(5), two equivalent Sr(6), and one Mn(2) atom to form distorted OSr5Mn octahedra that share corners with four equivalent O(7)Sr4MnFe octahedra, corners with four equivalent O(4)Sr5Mn octahedra, corners with eight equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(2)Sr5Fe octahedra, edges with two equivalent O(1)Sr5Mn octahedra, edges with four equivalent O(3)Sr5Mn octahedra, and faces with four equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 8-55°. In the fifth O site, O(5) is bonded to two equivalent Sr(1), two equivalent Sr(2), one Mn(3), and one Fe(1) atom to form distorted OSr4MnFe octahedra that share  a cornercorner with one O(2)Sr5Fe octahedra,  a cornercorner with one O(3)Sr5Mn octahedra, corners with four equivalent O(5)Sr4MnFe octahedra, corners with eight equivalent O(8)Sr4Mn2 octahedra, corners with eight equivalent O(7)Sr4MnFe octahedra, faces with four equivalent O(8)Sr4Mn2 octahedra, and faces with four equivalent O(7)Sr4MnFe octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the sixth O site, O(6) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), one Mn(1), and one Mn(2) 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 Fe(1) atom to form distorted OSr4MnFe octahedra that share  a cornercorner with one O(3)Sr5Mn octahedra,  a cornercorner with one O(4)Sr5Mn octahedra, corners with two equivalent O(5)Sr4MnFe octahedra, corners with two equivalent O(7)Sr4MnFe octahedra, corners with two equivalent O(2)Sr5Fe octahedra, corners with two equivalent O(1)Sr5Mn octahedra, corners with six equivalent O(8)Sr4Mn2 octahedra,  an edgeedge with one O(8)Sr4Mn2 octahedra, edges with two equivalent O(7)Sr4MnFe octahedra,  a faceface with one O(5)Sr4MnFe octahedra,  a faceface with one O(2)Sr5Fe octahedra,  a faceface with one O(1)Sr5Mn octahedra, and faces with four equivalent O(7)Sr4MnFe octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the eighth O site, O(8) is bonded to one Sr(1), one Sr(2), one Sr(5), one Sr(6), one Mn(2), and one Mn(3) atom to form distorted OSr4Mn2 octahedra that share  a cornercorner with one O(2)Sr5Fe octahedra,  a cornercorner with one O(1)Sr5Mn octahedra, corners with two equivalent O(8)Sr4Mn2 octahedra, corners with two equivalent O(5)Sr4MnFe octahedra, corners with two equivalent O(3)Sr5Mn octahedra, corners with two equivalent O(4)Sr5Mn octahedra, corners with six equivalent O(7)Sr4MnFe octahedra,  an edgeedge with one O(7)Sr4MnFe octahedra, edges with two equivalent O(8)Sr4Mn2 octahedra,  a faceface with one O(5)Sr4MnFe octahedra,  a faceface with one O(3)Sr5Mn octahedra,  a faceface with one O(4)Sr5Mn octahedra, and faces with four equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-60°.
Sr6Mn3FeO14 crystallizes in the orthorhombic Amm2 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent O(5), two equivalent O(6), four equivalent O(7), and four equivalent O(8) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(1)O12 cuboctahedra, faces with four equivalent Sr(2)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 Fe(1)O6 octahedra. Both Sr(1)-O(5) bond lengths are 2.76 Å. Both Sr(1)-O(6) bond lengths are 2.76 Å. All Sr(1)-O(7) bond lengths are 2.75 Å. All Sr(1)-O(8) bond lengths are 2.75 Å. In the second Sr site, Sr(2) is bonded to two equivalent O(5), two equivalent O(6), four equivalent O(7), and four equivalent O(8) atoms to form SrO12 cuboctahedra that share corners with four equivalent Sr(2)O12 cuboctahedra, faces with four equivalent Sr(1)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 Fe(1)O6 octahedra. Both Sr(2)-O(5) bond lengths are 2.76 Å. Both Sr(2)-O(6) bond lengths are 2.76 Å. All Sr(2)-O(7) bond lengths are 2.75 Å. All Sr(2)-O(8) bond lengths are 2.76 Å. In the third Sr site, Sr(3) is bonded in a 9-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), and four equivalent O(7) atoms. The Sr(3)-O(3) bond length is 2.51 Å. Both Sr(3)-O(1) bond lengths are 2.76 Å. Both Sr(3)-O(2) bond lengths are 2.77 Å. All Sr(3)-O(7) bond lengths are 2.63 Å. In the fourth Sr site, Sr(4) is bonded in a 9-coordinate geometry to one O(4), two equivalent O(1), two equivalent O(2), and four equivalent O(7) atoms. The Sr(4)-O(4) bond length is 2.52 Å. Both Sr(4)-O(1) bond lengths are 2.77 Å. Both Sr(4)-O(2) bond lengths are 2.77 Å. All Sr(4)-O(7) bond lengths are 2.63 Å. In the fifth Sr site, Sr(5) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(3), two equivalent O(4), and four equivalent O(8) atoms. The Sr(5)-O(1) bond length is 2.50 Å. Both Sr(5)-O(3) bond lengths are 2.76 Å. Both Sr(5)-O(4) bond lengths are 2.76 Å. All Sr(5)-O(8) bond lengths are 2.63 Å. In the sixth Sr site, Sr(6) is bonded in a 9-coordinate geometry to one O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(8) atoms. The Sr(6)-O(2) bond length is 2.49 Å. Both Sr(6)-O(3) bond lengths are 2.76 Å. Both Sr(6)-O(4) bond lengths are 2.76 Å. All Sr(6)-O(8) bond lengths are 2.63 Å. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(1), one O(6), and four equivalent O(7) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(2)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. The Mn(1)-O(1) bond length is 1.95 Å. The Mn(1)-O(6) bond length is 1.99 Å. All Mn(1)-O(7) bond lengths are 1.93 Å. In the second Mn site, Mn(2) is bonded to one O(4), one O(6), and four equivalent O(8) atoms to form MnO6 octahedra that share  a cornercorner with one Mn(1)O6 octahedra, corners with four equivalent Mn(3)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. The Mn(2)-O(4) bond length is 1.93 Å. The Mn(2)-O(6) bond length is 1.96 Å. All Mn(2)-O(8) bond lengths are 1.95 Å. In the third Mn site, Mn(3) is bonded to one O(3), one O(5), and four equivalent O(8) atoms to form MnO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with four equivalent Mn(2)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. The Mn(3)-O(3) bond length is 1.94 Å. The Mn(3)-O(5) bond length is 1.96 Å. All Mn(3)-O(8) bond lengths are 1.95 Å. Fe(1) is bonded to one O(2), one O(5), and four equivalent O(7) atoms to form FeO6 octahedra that share  a cornercorner with one Mn(3)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, faces with two equivalent Sr(1)O12 cuboctahedra, and faces with two equivalent Sr(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-2°. The Fe(1)-O(2) bond length is 1.97 Å. The Fe(1)-O(5) bond length is 1.98 Å. All Fe(1)-O(7) bond lengths are 1.97 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Sr(5), two equivalent Sr(3), two equivalent Sr(4), and one Mn(1) atom to form distorted OSr5Mn octahedra that share corners with four equivalent O(8)Sr4Mn2 octahedra, corners with four equivalent O(1)Sr5Mn octahedra, corners with eight equivalent O(7)Sr4MnFe octahedra, edges with two equivalent O(3)Sr5Mn octahedra, edges with two equivalent O(4)Sr5Mn octahedra, edges with four equivalent O(2)Sr5Fe octahedra, and faces with four equivalent O(7)Sr4MnFe octahedra. The corner-sharing octahedral tilt angles range from 9-55°. In the second O site, O(2) is bonded to one Sr(6), two equivalent Sr(3), two equivalent Sr(4), and one Fe(1) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(5)Sr4MnFe octahedra, corners with four equivalent O(8)Sr4Mn2 octahedra, corners with four equivalent O(2)Sr5Fe octahedra, corners with eight equivalent O(7)Sr4MnFe octahedra, edges with two equivalent O(3)Sr5Mn octahedra, edges with two equivalent O(4)Sr5Mn octahedra, edges with four equivalent O(1)Sr5Mn octahedra, and faces with four equivalent O(7)Sr4MnFe octahedra. The corner-sharing octahedral tilt angles range from 0-55°. In the third O site, O(3) is bonded to one Sr(3), two equivalent Sr(5), two equivalent Sr(6), and one Mn(3) atom to form distorted OSr5Mn octahedra that share  a cornercorner with one O(5)Sr4MnFe octahedra, corners with four equivalent O(7)Sr4MnFe octahedra, corners with four equivalent O(3)Sr5Mn octahedra, corners with eight equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(2)Sr5Fe octahedra, edges with two equivalent O(1)Sr5Mn octahedra, edges with four equivalent O(4)Sr5Mn octahedra, and faces with four equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-55°. In the fourth O site, O(4) is bonded to one Sr(4), two equivalent Sr(5), two equivalent Sr(6), and one Mn(2) atom to form distorted OSr5Mn octahedra that share corners with four equivalent O(7)Sr4MnFe octahedra, corners with four equivalent O(4)Sr5Mn octahedra, corners with eight equivalent O(8)Sr4Mn2 octahedra, edges with two equivalent O(2)Sr5Fe octahedra, edges with two equivalent O(1)Sr5Mn octahedra, edges with four equivalent O(3)Sr5Mn octahedra, and faces with four equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 8-55°. In the fifth O site, O(5) is bonded to two equivalent Sr(1), two equivalent Sr(2), one Mn(3), and one Fe(1) atom to form distorted OSr4MnFe octahedra that share  a cornercorner with one O(2)Sr5Fe octahedra,  a cornercorner with one O(3)Sr5Mn octahedra, corners with four equivalent O(5)Sr4MnFe octahedra, corners with eight equivalent O(8)Sr4Mn2 octahedra, corners with eight equivalent O(7)Sr4MnFe octahedra, faces with four equivalent O(8)Sr4Mn2 octahedra, and faces with four equivalent O(7)Sr4MnFe octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the sixth O site, O(6) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), one Mn(1), and one Mn(2) 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 Fe(1) atom to form distorted OSr4MnFe octahedra that share  a cornercorner with one O(3)Sr5Mn octahedra,  a cornercorner with one O(4)Sr5Mn octahedra, corners with two equivalent O(5)Sr4MnFe octahedra, corners with two equivalent O(7)Sr4MnFe octahedra, corners with two equivalent O(2)Sr5Fe octahedra, corners with two equivalent O(1)Sr5Mn octahedra, corners with six equivalent O(8)Sr4Mn2 octahedra,  an edgeedge with one O(8)Sr4Mn2 octahedra, edges with two equivalent O(7)Sr4MnFe octahedra,  a faceface with one O(5)Sr4MnFe octahedra,  a faceface with one O(2)Sr5Fe octahedra,  a faceface with one O(1)Sr5Mn octahedra, and faces with four equivalent O(7)Sr4MnFe octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the eighth O site, O(8) is bonded to one Sr(1), one Sr(2), one Sr(5), one Sr(6), one Mn(2), and one Mn(3) atom to form distorted OSr4Mn2 octahedra that share  a cornercorner with one O(2)Sr5Fe octahedra,  a cornercorner with one O(1)Sr5Mn octahedra, corners with two equivalent O(8)Sr4Mn2 octahedra, corners with two equivalent O(5)Sr4MnFe octahedra, corners with two equivalent O(3)Sr5Mn octahedra, corners with two equivalent O(4)Sr5Mn octahedra, corners with six equivalent O(7)Sr4MnFe octahedra,  an edgeedge with one O(7)Sr4MnFe octahedra, edges with two equivalent O(8)Sr4Mn2 octahedra,  a faceface with one O(5)Sr4MnFe octahedra,  a faceface with one O(3)Sr5Mn octahedra,  a faceface with one O(4)Sr5Mn octahedra, and faces with four equivalent O(8)Sr4Mn2 octahedra. The corner-sharing octahedral tilt angles range from 0-60°.