The material described by Sr12Fe8O27 crystallizes in the triclinic P-1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(10), one O(11), one O(3), one O(4), one O(5), one O(6), one O(7), and two equivalent O(1) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(6), one O(7), one O(9), and two equivalent O(4) atoms. In the third Sr site, Sr(3) is bonded in a distorted q6 geometry to one O(12), one O(14), one O(2), one O(3), one O(5), one O(6), one O(8), two equivalent O(11), and two equivalent O(13) atoms. In the fourth Sr site, Sr(4) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), one O(4), one O(8), and two equivalent O(7) atoms. In the fifth Sr site, Sr(5) is bonded in a distorted q6 geometry to one O(12), one O(14), one O(2), one O(3), one O(5), one O(6), one O(8), two equivalent O(13), and two equivalent O(9) atoms. In the sixth Sr site, Sr(6) is bonded in a 9-coordinate geometry to one O(1), one O(12), one O(4), one O(5), one O(7), one O(8), one O(9), and two equivalent O(10) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(12), one O(2), one O(5), and one O(6) atom to form corner-sharing FeO5 square pyramids. The corner-sharing octahedral tilt angles range from 10-12°. In the second Fe site, Fe(2) is bonded to one O(14), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, and corners with two equivalent Fe(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 0-1°. In the third Fe site, Fe(3) is bonded to one O(11), one O(12), one O(13), one O(3), one O(7), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with three equivalent Fe(4)O6 octahedra, and  a cornercorner with one Fe(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 1-2°. In the fourth Fe site, Fe(4) is bonded to one O(10), one O(11), one O(13), one O(6), one O(8), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with three equivalent Fe(3)O6 octahedra, and  a cornercorner with one Fe(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 1-2°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded to one Sr(2), one Sr(4), one Sr(6), two equivalent Sr(1), and one Fe(1) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra, corners with two equivalent O(8)Sr4Fe2 octahedra, corners with two equivalent O(9)Sr4Fe2 octahedra, corners with two equivalent O(10)Sr5Fe octahedra, corners with two equivalent O(7)Sr5Fe octahedra, corners with three equivalent O(11)Sr4Fe2 octahedra, corners with three equivalent O(3)Sr4Fe2 octahedra,  an edgeedge with one O(1)Sr5Fe octahedra, edges with two equivalent O(10)Sr5Fe octahedra, edges with two equivalent O(7)Sr5Fe octahedra, edges with three equivalent O(4)Sr5Fe octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra, and  a faceface with one O(6)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 10-54°. In the second O site, O(2) is bonded to one Sr(2), one Sr(3), one Sr(4), one Sr(5), one Fe(1), and one Fe(2) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(4)Sr5Fe octahedra, corners with two equivalent O(5)Sr4Fe2 octahedra, corners with two equivalent O(10)Sr5Fe octahedra, corners with three equivalent O(7)Sr5Fe octahedra, corners with four equivalent O(13)Sr4Fe2 octahedra,  an edgeedge with one O(11)Sr4Fe2 octahedra,  an edgeedge with one O(5)Sr4Fe2 octahedra,  an edgeedge with one O(9)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra,  a faceface with one O(1)Sr5Fe octahedra, and  a faceface with one O(4)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 5-68°. In the third O site, O(3) is bonded to one Sr(1), one Sr(2), one Sr(3), one Sr(5), one Fe(2), and one Fe(3) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(4)Sr5Fe octahedra, corners with two equivalent O(13)Sr4Fe2 octahedra, corners with two equivalent O(10)Sr5Fe octahedra, corners with three equivalent O(12)Sr4Fe2 octahedra, corners with three equivalent O(1)Sr5Fe octahedra,  an edgeedge with one O(8)Sr4Fe2 octahedra, edges with two equivalent O(6)Sr4Fe2 octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(13)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra,  a faceface with one O(9)Sr4Fe2 octahedra,  a faceface with one O(4)Sr5Fe octahedra, and  a faceface with one O(7)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the fourth O site, O(4) is bonded to one Sr(1), one Sr(4), one Sr(6), two equivalent Sr(2), and one Fe(2) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra, corners with two equivalent O(11)Sr4Fe2 octahedra, corners with two equivalent O(12)Sr4Fe2 octahedra, corners with two equivalent O(10)Sr5Fe octahedra, corners with two equivalent O(7)Sr5Fe octahedra, corners with three equivalent O(6)Sr4Fe2 octahedra, corners with three equivalent O(9)Sr4Fe2 octahedra,  an edgeedge with one O(4)Sr5Fe octahedra, edges with two equivalent O(10)Sr5Fe octahedra, edges with two equivalent O(7)Sr5Fe octahedra, edges with three equivalent O(1)Sr5Fe octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra, and  a faceface with one O(8)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 8-58°. In the fifth O site, O(5) is bonded to one Sr(1), one Sr(3), one Sr(5), one Sr(6), one Fe(1), and one Fe(2) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(1)Sr5Fe octahedra, corners with two equivalent O(2)Sr4Fe2 octahedra, corners with two equivalent O(7)Sr5Fe octahedra, corners with three equivalent O(10)Sr5Fe octahedra, corners with four equivalent O(13)Sr4Fe2 octahedra,  an edgeedge with one O(11)Sr4Fe2 octahedra,  an edgeedge with one O(2)Sr4Fe2 octahedra,  an edgeedge with one O(9)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra,  a faceface with one O(1)Sr5Fe octahedra, and  a faceface with one O(4)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 5-68°. In the sixth O site, O(6) is bonded to one Sr(1), one Sr(2), one Sr(3), one Sr(5), one Fe(1), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(1)Sr5Fe octahedra, corners with two equivalent O(13)Sr4Fe2 octahedra, corners with two equivalent O(7)Sr5Fe octahedra, corners with three equivalent O(8)Sr4Fe2 octahedra, corners with three equivalent O(4)Sr5Fe octahedra,  an edgeedge with one O(12)Sr4Fe2 octahedra, edges with two equivalent O(3)Sr4Fe2 octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(13)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra,  a faceface with one O(9)Sr4Fe2 octahedra,  a faceface with one O(1)Sr5Fe octahedra, and  a faceface with one O(10)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 4-68°. In the seventh O site, O(7) is bonded to one Sr(1), one Sr(2), one Sr(6), two equivalent Sr(4), and one Fe(3) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(13)Sr4Fe2 octahedra, corners with two equivalent O(5)Sr4Fe2 octahedra, corners with two equivalent O(6)Sr4Fe2 octahedra, corners with two equivalent O(1)Sr5Fe octahedra, corners with two equivalent O(4)Sr5Fe octahedra, corners with three equivalent O(2)Sr4Fe2 octahedra, corners with three equivalent O(8)Sr4Fe2 octahedra,  an edgeedge with one O(7)Sr5Fe octahedra, edges with two equivalent O(1)Sr5Fe octahedra, edges with two equivalent O(4)Sr5Fe octahedra, edges with three equivalent O(10)Sr5Fe octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra, and  a faceface with one O(9)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 1-59°. In the eighth O site, O(8) is bonded to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Fe(2), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(10)Sr5Fe octahedra, corners with two equivalent O(13)Sr4Fe2 octahedra, corners with two equivalent O(1)Sr5Fe octahedra, corners with three equivalent O(6)Sr4Fe2 octahedra, corners with three equivalent O(7)Sr5Fe octahedra,  an edgeedge with one O(3)Sr4Fe2 octahedra, edges with two equivalent O(12)Sr4Fe2 octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(13)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra,  a faceface with one O(9)Sr4Fe2 octahedra,  a faceface with one O(10)Sr5Fe octahedra, and  a faceface with one O(4)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the ninth O site, O(9) is bonded to one Sr(2), one Sr(6), two equivalent Sr(5), one Fe(3), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(10)Sr5Fe octahedra, corners with two equivalent O(11)Sr4Fe2 octahedra, corners with two equivalent O(1)Sr5Fe octahedra, corners with three equivalent O(4)Sr5Fe octahedra,  an edgeedge with one O(2)Sr4Fe2 octahedra,  an edgeedge with one O(5)Sr4Fe2 octahedra,  an edgeedge with one O(9)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra,  a faceface with one O(10)Sr5Fe octahedra,  a faceface with one O(7)Sr5Fe octahedra, and faces with two equivalent O(13)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 2-60°. In the tenth O site, O(10) is bonded to one Sr(1), one Sr(2), one Sr(4), two equivalent Sr(6), and one Fe(4) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(13)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra, corners with two equivalent O(2)Sr4Fe2 octahedra, corners with two equivalent O(3)Sr4Fe2 octahedra, corners with two equivalent O(1)Sr5Fe octahedra, corners with two equivalent O(4)Sr5Fe octahedra, corners with three equivalent O(12)Sr4Fe2 octahedra, corners with three equivalent O(5)Sr4Fe2 octahedra,  an edgeedge with one O(10)Sr5Fe octahedra, edges with two equivalent O(1)Sr5Fe octahedra, edges with two equivalent O(4)Sr5Fe octahedra, edges with three equivalent O(7)Sr5Fe octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra, and  a faceface with one O(9)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-58°. In the eleventh O site, O(11) is bonded to one Sr(1), one Sr(4), two equivalent Sr(3), one Fe(3), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(7)Sr5Fe octahedra, corners with two equivalent O(9)Sr4Fe2 octahedra, corners with two equivalent O(4)Sr5Fe octahedra, corners with three equivalent O(1)Sr5Fe octahedra,  an edgeedge with one O(11)Sr4Fe2 octahedra,  an edgeedge with one O(2)Sr4Fe2 octahedra,  an edgeedge with one O(5)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra,  a faceface with one O(10)Sr5Fe octahedra,  a faceface with one O(7)Sr5Fe octahedra, and faces with two equivalent O(13)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 2-60°. In the twelfth O site, O(12) is bonded to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Fe(1), and one Fe(3) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(7)Sr5Fe octahedra, corners with two equivalent O(13)Sr4Fe2 octahedra, corners with two equivalent O(4)Sr5Fe octahedra, corners with three equivalent O(3)Sr4Fe2 octahedra, corners with three equivalent O(10)Sr5Fe octahedra,  an edgeedge with one O(6)Sr4Fe2 octahedra, edges with two equivalent O(8)Sr4Fe2 octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(13)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra,  a faceface with one O(9)Sr4Fe2 octahedra,  a faceface with one O(1)Sr5Fe octahedra, and  a faceface with one O(7)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 5-68°. In the thirteenth O site, O(13) is bonded to two equivalent Sr(3), two equivalent Sr(5), one Fe(3), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(10)Sr5Fe octahedra,  a cornercorner with one O(7)Sr5Fe octahedra, corners with two equivalent O(12)Sr4Fe2 octahedra, corners with two equivalent O(3)Sr4Fe2 octahedra, corners with two equivalent O(6)Sr4Fe2 octahedra, corners with two equivalent O(8)Sr4Fe2 octahedra, corners with four equivalent O(2)Sr4Fe2 octahedra, corners with four equivalent O(5)Sr4Fe2 octahedra, edges with two equivalent O(13)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra, faces with two equivalent O(11)Sr4Fe2 octahedra, and faces with two equivalent O(9)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the fourteenth O site, O(14) is bonded in a distorted linear geometry to two equivalent Sr(3), two equivalent Sr(5), and two equivalent Fe(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr12Fe8O27
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.717
_cell_length_b   8.615
_cell_length_c   10.417
_cell_angle_alpha   94.716
_cell_angle_beta   100.693
_cell_angle_gamma   116.594
_symmetry_Int_Tables_number   1
_cell_volume   597.710
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Sr  Sr0  1  0.240  0.160  0.638  1.0
  Sr  Sr1  1  0.738  0.159  0.635  1.0
  Sr  Sr2  1  0.386  0.258  0.000  1.0
  Sr  Sr3  1  0.513  0.343  0.365  1.0
  Sr  Sr4  1  0.871  0.257  1.000  1.0
  Sr  Sr5  1  0.011  0.341  0.365  1.0
  Sr  Sr6  1  0.989  0.659  0.635  1.0
  Sr  Sr7  1  0.487  0.657  0.635  1.0
  Sr  Sr8  1  0.129  0.743  0.000  1.0
  Sr  Sr9  1  0.262  0.841  0.365  1.0
  Sr  Sr10  1  0.760  0.840  0.362  1.0
  Sr  Sr11  1  0.614  0.742  1.000  1.0
  Fe  Fe12  1  0.078  0.052  0.206  1.0
  Fe  Fe13  1  0.571  0.048  0.191  1.0
  Fe  Fe14  1  0.679  0.454  0.807  1.0
  Fe  Fe15  1  0.177  0.451  0.807  1.0
  Fe  Fe16  1  0.823  0.549  0.193  1.0
  Fe  Fe17  1  0.321  0.546  0.193  1.0
  Fe  Fe18  1  0.429  0.952  0.809  1.0
  Fe  Fe19  1  0.922  0.948  0.794  1.0
  O  O20  1  0.152  0.100  0.396  1.0
  O  O21  1  0.306  0.045  0.180  1.0
  O  O22  1  0.553  0.200  0.809  1.0
  O  O23  1  0.642  0.096  0.382  1.0
  O  O24  1  0.830  0.045  0.182  1.0
  O  O25  1  0.052  0.195  0.820  1.0
  O  O26  1  0.612  0.412  0.616  1.0
  O  O27  1  0.695  0.295  0.191  1.0
  O  O28  1  0.929  0.453  0.810  1.0
  O  O29  1  0.101  0.398  0.616  1.0
  O  O30  1  0.429  0.453  0.810  1.0
  O  O31  1  0.187  0.285  0.180  1.0
  O  O32  1  0.813  0.715  0.820  1.0
  O  O33  1  0.749  0.498  0.000  1.0
  O  O34  1  0.571  0.547  0.190  1.0
  O  O35  1  0.899  0.602  0.384  1.0
  O  O36  1  0.305  0.705  0.809  1.0
  O  O37  1  0.388  0.588  0.384  1.0
  O  O38  1  0.251  0.502  1.000  1.0
  O  O39  1  0.071  0.547  0.190  1.0
  O  O40  1  0.694  0.955  0.820  1.0
  O  O41  1  0.358  0.904  0.618  1.0
  O  O42  1  0.948  0.805  0.180  1.0
  O  O43  1  0.170  0.955  0.818  1.0
  O  O44  1  0.848  0.900  0.604  1.0
  O  O45  1  0.447  0.800  0.191  1.0
  O  O46  1  0.500  0.000  0.000  1.0
[/CIF]
.
The material described by Sr12Fe8O27 crystallizes in the triclinic P-1 space group. There are six inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 9-coordinate geometry to one O(10), one O(11), one O(3), one O(4), one O(5), one O(6), one O(7), and two equivalent O(1) atoms. In the second Sr site, Sr(2) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(2), one O(3), one O(6), one O(7), one O(9), and two equivalent O(4) atoms. In the third Sr site, Sr(3) is bonded in a distorted q6 geometry to one O(12), one O(14), one O(2), one O(3), one O(5), one O(6), one O(8), two equivalent O(11), and two equivalent O(13) atoms. In the fourth Sr site, Sr(4) is bonded in a 9-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), one O(4), one O(8), and two equivalent O(7) atoms. In the fifth Sr site, Sr(5) is bonded in a distorted q6 geometry to one O(12), one O(14), one O(2), one O(3), one O(5), one O(6), one O(8), two equivalent O(13), and two equivalent O(9) atoms. In the sixth Sr site, Sr(6) is bonded in a 9-coordinate geometry to one O(1), one O(12), one O(4), one O(5), one O(7), one O(8), one O(9), and two equivalent O(10) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(12), one O(2), one O(5), and one O(6) atom to form corner-sharing FeO5 square pyramids. The corner-sharing octahedral tilt angles range from 10-12°. In the second Fe site, Fe(2) is bonded to one O(14), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, and corners with two equivalent Fe(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 0-1°. In the third Fe site, Fe(3) is bonded to one O(11), one O(12), one O(13), one O(3), one O(7), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with three equivalent Fe(4)O6 octahedra, and  a cornercorner with one Fe(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 1-2°. In the fourth Fe site, Fe(4) is bonded to one O(10), one O(11), one O(13), one O(6), one O(8), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with three equivalent Fe(3)O6 octahedra, and  a cornercorner with one Fe(1)O5 square pyramid. The corner-sharing octahedral tilt angles range from 1-2°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded to one Sr(2), one Sr(4), one Sr(6), two equivalent Sr(1), and one Fe(1) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra, corners with two equivalent O(8)Sr4Fe2 octahedra, corners with two equivalent O(9)Sr4Fe2 octahedra, corners with two equivalent O(10)Sr5Fe octahedra, corners with two equivalent O(7)Sr5Fe octahedra, corners with three equivalent O(11)Sr4Fe2 octahedra, corners with three equivalent O(3)Sr4Fe2 octahedra,  an edgeedge with one O(1)Sr5Fe octahedra, edges with two equivalent O(10)Sr5Fe octahedra, edges with two equivalent O(7)Sr5Fe octahedra, edges with three equivalent O(4)Sr5Fe octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra, and  a faceface with one O(6)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 10-54°. In the second O site, O(2) is bonded to one Sr(2), one Sr(3), one Sr(4), one Sr(5), one Fe(1), and one Fe(2) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(4)Sr5Fe octahedra, corners with two equivalent O(5)Sr4Fe2 octahedra, corners with two equivalent O(10)Sr5Fe octahedra, corners with three equivalent O(7)Sr5Fe octahedra, corners with four equivalent O(13)Sr4Fe2 octahedra,  an edgeedge with one O(11)Sr4Fe2 octahedra,  an edgeedge with one O(5)Sr4Fe2 octahedra,  an edgeedge with one O(9)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra,  a faceface with one O(1)Sr5Fe octahedra, and  a faceface with one O(4)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 5-68°. In the third O site, O(3) is bonded to one Sr(1), one Sr(2), one Sr(3), one Sr(5), one Fe(2), and one Fe(3) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(4)Sr5Fe octahedra, corners with two equivalent O(13)Sr4Fe2 octahedra, corners with two equivalent O(10)Sr5Fe octahedra, corners with three equivalent O(12)Sr4Fe2 octahedra, corners with three equivalent O(1)Sr5Fe octahedra,  an edgeedge with one O(8)Sr4Fe2 octahedra, edges with two equivalent O(6)Sr4Fe2 octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(13)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra,  a faceface with one O(9)Sr4Fe2 octahedra,  a faceface with one O(4)Sr5Fe octahedra, and  a faceface with one O(7)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the fourth O site, O(4) is bonded to one Sr(1), one Sr(4), one Sr(6), two equivalent Sr(2), and one Fe(2) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra, corners with two equivalent O(11)Sr4Fe2 octahedra, corners with two equivalent O(12)Sr4Fe2 octahedra, corners with two equivalent O(10)Sr5Fe octahedra, corners with two equivalent O(7)Sr5Fe octahedra, corners with three equivalent O(6)Sr4Fe2 octahedra, corners with three equivalent O(9)Sr4Fe2 octahedra,  an edgeedge with one O(4)Sr5Fe octahedra, edges with two equivalent O(10)Sr5Fe octahedra, edges with two equivalent O(7)Sr5Fe octahedra, edges with three equivalent O(1)Sr5Fe octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra, and  a faceface with one O(8)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 8-58°. In the fifth O site, O(5) is bonded to one Sr(1), one Sr(3), one Sr(5), one Sr(6), one Fe(1), and one Fe(2) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(1)Sr5Fe octahedra, corners with two equivalent O(2)Sr4Fe2 octahedra, corners with two equivalent O(7)Sr5Fe octahedra, corners with three equivalent O(10)Sr5Fe octahedra, corners with four equivalent O(13)Sr4Fe2 octahedra,  an edgeedge with one O(11)Sr4Fe2 octahedra,  an edgeedge with one O(2)Sr4Fe2 octahedra,  an edgeedge with one O(9)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra,  a faceface with one O(1)Sr5Fe octahedra, and  a faceface with one O(4)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 5-68°. In the sixth O site, O(6) is bonded to one Sr(1), one Sr(2), one Sr(3), one Sr(5), one Fe(1), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(1)Sr5Fe octahedra, corners with two equivalent O(13)Sr4Fe2 octahedra, corners with two equivalent O(7)Sr5Fe octahedra, corners with three equivalent O(8)Sr4Fe2 octahedra, corners with three equivalent O(4)Sr5Fe octahedra,  an edgeedge with one O(12)Sr4Fe2 octahedra, edges with two equivalent O(3)Sr4Fe2 octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(13)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra,  a faceface with one O(9)Sr4Fe2 octahedra,  a faceface with one O(1)Sr5Fe octahedra, and  a faceface with one O(10)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 4-68°. In the seventh O site, O(7) is bonded to one Sr(1), one Sr(2), one Sr(6), two equivalent Sr(4), and one Fe(3) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(13)Sr4Fe2 octahedra, corners with two equivalent O(5)Sr4Fe2 octahedra, corners with two equivalent O(6)Sr4Fe2 octahedra, corners with two equivalent O(1)Sr5Fe octahedra, corners with two equivalent O(4)Sr5Fe octahedra, corners with three equivalent O(2)Sr4Fe2 octahedra, corners with three equivalent O(8)Sr4Fe2 octahedra,  an edgeedge with one O(7)Sr5Fe octahedra, edges with two equivalent O(1)Sr5Fe octahedra, edges with two equivalent O(4)Sr5Fe octahedra, edges with three equivalent O(10)Sr5Fe octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra, and  a faceface with one O(9)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 1-59°. In the eighth O site, O(8) is bonded to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Fe(2), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(10)Sr5Fe octahedra, corners with two equivalent O(13)Sr4Fe2 octahedra, corners with two equivalent O(1)Sr5Fe octahedra, corners with three equivalent O(6)Sr4Fe2 octahedra, corners with three equivalent O(7)Sr5Fe octahedra,  an edgeedge with one O(3)Sr4Fe2 octahedra, edges with two equivalent O(12)Sr4Fe2 octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(13)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra,  a faceface with one O(9)Sr4Fe2 octahedra,  a faceface with one O(10)Sr5Fe octahedra, and  a faceface with one O(4)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-60°. In the ninth O site, O(9) is bonded to one Sr(2), one Sr(6), two equivalent Sr(5), one Fe(3), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(10)Sr5Fe octahedra, corners with two equivalent O(11)Sr4Fe2 octahedra, corners with two equivalent O(1)Sr5Fe octahedra, corners with three equivalent O(4)Sr5Fe octahedra,  an edgeedge with one O(2)Sr4Fe2 octahedra,  an edgeedge with one O(5)Sr4Fe2 octahedra,  an edgeedge with one O(9)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra,  a faceface with one O(10)Sr5Fe octahedra,  a faceface with one O(7)Sr5Fe octahedra, and faces with two equivalent O(13)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 2-60°. In the tenth O site, O(10) is bonded to one Sr(1), one Sr(2), one Sr(4), two equivalent Sr(6), and one Fe(4) atom to form distorted OSr5Fe octahedra that share  a cornercorner with one O(13)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra, corners with two equivalent O(2)Sr4Fe2 octahedra, corners with two equivalent O(3)Sr4Fe2 octahedra, corners with two equivalent O(1)Sr5Fe octahedra, corners with two equivalent O(4)Sr5Fe octahedra, corners with three equivalent O(12)Sr4Fe2 octahedra, corners with three equivalent O(5)Sr4Fe2 octahedra,  an edgeedge with one O(10)Sr5Fe octahedra, edges with two equivalent O(1)Sr5Fe octahedra, edges with two equivalent O(4)Sr5Fe octahedra, edges with three equivalent O(7)Sr5Fe octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra, and  a faceface with one O(9)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-58°. In the eleventh O site, O(11) is bonded to one Sr(1), one Sr(4), two equivalent Sr(3), one Fe(3), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(12)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(3)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(8)Sr4Fe2 octahedra,  a cornercorner with one O(7)Sr5Fe octahedra, corners with two equivalent O(9)Sr4Fe2 octahedra, corners with two equivalent O(4)Sr5Fe octahedra, corners with three equivalent O(1)Sr5Fe octahedra,  an edgeedge with one O(11)Sr4Fe2 octahedra,  an edgeedge with one O(2)Sr4Fe2 octahedra,  an edgeedge with one O(5)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra,  a faceface with one O(10)Sr5Fe octahedra,  a faceface with one O(7)Sr5Fe octahedra, and faces with two equivalent O(13)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 2-60°. In the twelfth O site, O(12) is bonded to one Sr(3), one Sr(4), one Sr(5), one Sr(6), one Fe(1), and one Fe(3) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(11)Sr4Fe2 octahedra,  a cornercorner with one O(2)Sr4Fe2 octahedra,  a cornercorner with one O(5)Sr4Fe2 octahedra,  a cornercorner with one O(6)Sr4Fe2 octahedra,  a cornercorner with one O(9)Sr4Fe2 octahedra,  a cornercorner with one O(7)Sr5Fe octahedra, corners with two equivalent O(13)Sr4Fe2 octahedra, corners with two equivalent O(4)Sr5Fe octahedra, corners with three equivalent O(3)Sr4Fe2 octahedra, corners with three equivalent O(10)Sr5Fe octahedra,  an edgeedge with one O(6)Sr4Fe2 octahedra, edges with two equivalent O(8)Sr4Fe2 octahedra,  a faceface with one O(11)Sr4Fe2 octahedra,  a faceface with one O(13)Sr4Fe2 octahedra,  a faceface with one O(2)Sr4Fe2 octahedra,  a faceface with one O(5)Sr4Fe2 octahedra,  a faceface with one O(9)Sr4Fe2 octahedra,  a faceface with one O(1)Sr5Fe octahedra, and  a faceface with one O(7)Sr5Fe octahedra. The corner-sharing octahedral tilt angles range from 5-68°. In the thirteenth O site, O(13) is bonded to two equivalent Sr(3), two equivalent Sr(5), one Fe(3), and one Fe(4) atom to form distorted OSr4Fe2 octahedra that share  a cornercorner with one O(10)Sr5Fe octahedra,  a cornercorner with one O(7)Sr5Fe octahedra, corners with two equivalent O(12)Sr4Fe2 octahedra, corners with two equivalent O(3)Sr4Fe2 octahedra, corners with two equivalent O(6)Sr4Fe2 octahedra, corners with two equivalent O(8)Sr4Fe2 octahedra, corners with four equivalent O(2)Sr4Fe2 octahedra, corners with four equivalent O(5)Sr4Fe2 octahedra, edges with two equivalent O(13)Sr4Fe2 octahedra,  a faceface with one O(12)Sr4Fe2 octahedra,  a faceface with one O(3)Sr4Fe2 octahedra,  a faceface with one O(6)Sr4Fe2 octahedra,  a faceface with one O(8)Sr4Fe2 octahedra, faces with two equivalent O(11)Sr4Fe2 octahedra, and faces with two equivalent O(9)Sr4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the fourteenth O site, O(14) is bonded in a distorted linear geometry to two equivalent Sr(3), two equivalent Sr(5), and two equivalent Fe(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr12Fe8O27
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.717
_cell_length_b   8.615
_cell_length_c   10.417
_cell_angle_alpha   94.716
_cell_angle_beta   100.693
_cell_angle_gamma   116.594
_symmetry_Int_Tables_number   1
_cell_volume   597.710
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Sr  Sr0  1  0.240  0.160  0.638  1.0
  Sr  Sr1  1  0.738  0.159  0.635  1.0
  Sr  Sr2  1  0.386  0.258  0.000  1.0
  Sr  Sr3  1  0.513  0.343  0.365  1.0
  Sr  Sr4  1  0.871  0.257  1.000  1.0
  Sr  Sr5  1  0.011  0.341  0.365  1.0
  Sr  Sr6  1  0.989  0.659  0.635  1.0
  Sr  Sr7  1  0.487  0.657  0.635  1.0
  Sr  Sr8  1  0.129  0.743  0.000  1.0
  Sr  Sr9  1  0.262  0.841  0.365  1.0
  Sr  Sr10  1  0.760  0.840  0.362  1.0
  Sr  Sr11  1  0.614  0.742  1.000  1.0
  Fe  Fe12  1  0.078  0.052  0.206  1.0
  Fe  Fe13  1  0.571  0.048  0.191  1.0
  Fe  Fe14  1  0.679  0.454  0.807  1.0
  Fe  Fe15  1  0.177  0.451  0.807  1.0
  Fe  Fe16  1  0.823  0.549  0.193  1.0
  Fe  Fe17  1  0.321  0.546  0.193  1.0
  Fe  Fe18  1  0.429  0.952  0.809  1.0
  Fe  Fe19  1  0.922  0.948  0.794  1.0
  O  O20  1  0.152  0.100  0.396  1.0
  O  O21  1  0.306  0.045  0.180  1.0
  O  O22  1  0.553  0.200  0.809  1.0
  O  O23  1  0.642  0.096  0.382  1.0
  O  O24  1  0.830  0.045  0.182  1.0
  O  O25  1  0.052  0.195  0.820  1.0
  O  O26  1  0.612  0.412  0.616  1.0
  O  O27  1  0.695  0.295  0.191  1.0
  O  O28  1  0.929  0.453  0.810  1.0
  O  O29  1  0.101  0.398  0.616  1.0
  O  O30  1  0.429  0.453  0.810  1.0
  O  O31  1  0.187  0.285  0.180  1.0
  O  O32  1  0.813  0.715  0.820  1.0
  O  O33  1  0.749  0.498  0.000  1.0
  O  O34  1  0.571  0.547  0.190  1.0
  O  O35  1  0.899  0.602  0.384  1.0
  O  O36  1  0.305  0.705  0.809  1.0
  O  O37  1  0.388  0.588  0.384  1.0
  O  O38  1  0.251  0.502  1.000  1.0
  O  O39  1  0.071  0.547  0.190  1.0
  O  O40  1  0.694  0.955  0.820  1.0
  O  O41  1  0.358  0.904  0.618  1.0
  O  O42  1  0.948  0.805  0.180  1.0
  O  O43  1  0.170  0.955  0.818  1.0
  O  O44  1  0.848  0.900  0.604  1.0
  O  O45  1  0.447  0.800  0.191  1.0
  O  O46  1  0.500  0.000  0.000  1.0
[/CIF]
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