The material described by Fe7SiO10 crystallizes in the monoclinic P2_1/m space group. There are seven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(8), two equivalent O(10), and three equivalent O(9) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(6)O6 octahedra, corners with four equivalent Fe(4)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, edges with two equivalent Fe(6)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and edges with four equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the second Fe site, Fe(2) is bonded to one O(4), two equivalent O(2), and three equivalent O(1) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(3)O6 octahedra, corners with four equivalent Fe(7)O6 octahedra,  a cornercorner with one Fe(5)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, edges with four equivalent Fe(2)O6 octahedra, and edges with four equivalent Fe(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-11°. In the third Fe site, Fe(3) is bonded to one O(1), one O(6), two equivalent O(3), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with four equivalent Fe(5)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(7)O6 octahedra. The corner-sharing octahedral tilt angles are 4°. In the fourth Fe site, Fe(4) is bonded to one O(7), two equivalent O(9), and three equivalent O(10) atoms to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, edges with two equivalent Fe(6)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and edges with four equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-14°. In the fifth Fe site, Fe(5) is bonded to one O(3), one O(4), and two equivalent O(5) atoms to form FeO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(7)O6 octahedra, corners with two equivalent Fe(6)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra, and corners with two equivalent Fe(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 54-62°. In the sixth Fe site, Fe(6) is bonded to one O(5), one O(9), two equivalent O(7), and two equivalent O(8) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Fe(5)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and edges with two equivalent Fe(6)O6 octahedra. The corner-sharing octahedra are not tilted. In the seventh Fe site, Fe(7) is bonded to one O(3), two equivalent O(1), and three equivalent O(2) atoms to form FeO6 octahedra that share corners with four equivalent Fe(2)O6 octahedra,  a cornercorner with one Fe(5)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, edges with four equivalent Fe(2)O6 octahedra, and edges with four equivalent Fe(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 9-11°. Si(1) is bonded to one O(7), one O(8), and two equivalent O(6) atoms to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with four equivalent Fe(6)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-60°. There are ten inequivalent O sites. In the first O site, O(9) is bonded to one Fe(6), two equivalent Fe(4), and three equivalent Fe(1) atoms to form OFe6 octahedra that share corners with four equivalent O(10)Fe5 square pyramids, edges with four equivalent O(9)Fe6 octahedra, and edges with four equivalent O(10)Fe5 square pyramids. In the second O site, O(10) is bonded to two equivalent Fe(1) and three equivalent Fe(4) atoms to form OFe5 square pyramids that share corners with four equivalent O(9)Fe6 octahedra, edges with four equivalent O(9)Fe6 octahedra, and edges with four equivalent O(10)Fe5 square pyramids. The corner-sharing octahedral tilt angles are 3°. In the third O site, O(1) is bonded to one Fe(3), two equivalent Fe(7), and three equivalent Fe(2) atoms to form OFe6 octahedra that share corners with four equivalent O(2)Fe5 square pyramids,  a cornercorner with one O(4)Fe4 tetrahedra, edges with four equivalent O(1)Fe6 octahedra, edges with four equivalent O(2)Fe5 square pyramids, edges with two equivalent O(3)Fe4 tetrahedra, and edges with two equivalent O(4)Fe4 tetrahedra. In the fourth O site, O(2) is bonded to two equivalent Fe(2) and three equivalent Fe(7) atoms to form OFe5 square pyramids that share corners with four equivalent O(1)Fe6 octahedra, corners with two equivalent O(4)Fe4 tetrahedra, corners with three equivalent O(3)Fe4 tetrahedra, edges with four equivalent O(1)Fe6 octahedra, and edges with four equivalent O(2)Fe5 square pyramids. The corner-sharing octahedral tilt angles range from 9-11°. In the fifth O site, O(3) is bonded to one Fe(5), one Fe(7), and two equivalent Fe(3) atoms to form distorted OFe4 tetrahedra that share corners with three equivalent O(2)Fe5 square pyramids, corners with two equivalent O(3)Fe4 tetrahedra, corners with three equivalent O(4)Fe4 tetrahedra, edges with two equivalent O(1)Fe6 octahedra, and  an edgeedge with one O(4)Fe4 tetrahedra. In the sixth O site, O(4) is bonded to one Fe(2), one Fe(5), and two equivalent Fe(3) atoms to form distorted OFe4 tetrahedra that share  a cornercorner with one O(1)Fe6 octahedra, corners with two equivalent O(2)Fe5 square pyramids, corners with two equivalent O(4)Fe4 tetrahedra, corners with three equivalent O(3)Fe4 tetrahedra, edges with two equivalent O(1)Fe6 octahedra, and  an edgeedge with one O(3)Fe4 tetrahedra. The corner-sharing octahedral tilt angles are 2°. In the seventh O site, O(5) is bonded in a trigonal planar geometry to one Fe(6) and two equivalent Fe(5) atoms. In the eighth O site, O(6) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Si(1) atoms. In the ninth O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Fe(4), two equivalent Fe(6), and one Si(1) atom. In the tenth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Fe(1), two equivalent Fe(6), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe7SiO10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.050
_cell_length_b   6.056
_cell_length_c   21.924
_cell_angle_alpha   82.201
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   401.196
_cell_formula_units_Z   2
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
  Fe  Fe0  1  0.250  0.846  0.552  1.0
  Fe  Fe1  1  0.750  0.344  0.055  1.0
  Fe  Fe2  1  0.750  0.455  0.839  1.0
  Fe  Fe3  1  0.250  0.545  0.161  1.0
  Fe  Fe4  1  0.250  0.360  0.554  1.0
  Fe  Fe5  1  0.750  0.640  0.446  1.0
  Fe  Fe6  1  0.250  0.656  0.945  1.0
  Fe  Fe7  1  0.750  0.154  0.448  1.0
  Fe  Fe8  1  0.250  0.974  0.804  1.0
  Fe  Fe9  1  0.750  0.026  0.196  1.0
  Fe  Fe10  1  0.750  0.044  0.659  1.0
  Fe  Fe11  1  0.250  0.956  0.341  1.0
  Fe  Fe12  1  0.750  0.853  0.053  1.0
  Fe  Fe13  1  0.250  0.147  0.947  1.0
  Si  Si14  1  0.750  0.468  0.309  1.0
  Si  Si15  1  0.250  0.532  0.691  1.0
  O  O16  1  0.750  0.383  0.954  1.0
  O  O17  1  0.250  0.617  0.046  1.0
  O  O18  1  0.750  0.911  0.956  1.0
  O  O19  1  0.250  0.089  0.044  1.0
  O  O20  1  0.250  0.212  0.854  1.0
  O  O21  1  0.750  0.788  0.146  1.0
  O  O22  1  0.250  0.683  0.850  1.0
  O  O23  1  0.750  0.317  0.150  1.0
  O  O24  1  0.750  0.005  0.753  1.0
  O  O25  1  0.250  0.995  0.247  1.0
  O  O26  1  0.750  0.509  0.731  1.0
  O  O27  1  0.250  0.491  0.269  1.0
  O  O28  1  0.250  0.323  0.651  1.0
  O  O29  1  0.750  0.677  0.349  1.0
  O  O30  1  0.250  0.784  0.654  1.0
  O  O31  1  0.750  0.216  0.346  1.0
  O  O32  1  0.750  0.094  0.561  1.0
  O  O33  1  0.250  0.906  0.439  1.0
  O  O34  1  0.250  0.382  0.459  1.0
  O  O35  1  0.750  0.618  0.541  1.0
[/CIF]
.
The material described by Fe7SiO10 crystallizes in the monoclinic P2_1/m space group. There are seven inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(8), two equivalent O(10), and three equivalent O(9) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(6)O6 octahedra, corners with four equivalent Fe(4)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, edges with two equivalent Fe(6)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and edges with four equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the second Fe site, Fe(2) is bonded to one O(4), two equivalent O(2), and three equivalent O(1) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(3)O6 octahedra, corners with four equivalent Fe(7)O6 octahedra,  a cornercorner with one Fe(5)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, edges with four equivalent Fe(2)O6 octahedra, and edges with four equivalent Fe(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-11°. In the third Fe site, Fe(3) is bonded to one O(1), one O(6), two equivalent O(3), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Si(1)O4 tetrahedra, corners with four equivalent Fe(5)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with two equivalent Fe(7)O6 octahedra. The corner-sharing octahedral tilt angles are 4°. In the fourth Fe site, Fe(4) is bonded to one O(7), two equivalent O(9), and three equivalent O(10) atoms to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, edges with two equivalent Fe(6)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and edges with four equivalent Fe(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-14°. In the fifth Fe site, Fe(5) is bonded to one O(3), one O(4), and two equivalent O(5) atoms to form FeO4 tetrahedra that share  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(7)O6 octahedra, corners with two equivalent Fe(6)O6 octahedra, corners with four equivalent Fe(3)O6 octahedra, and corners with two equivalent Fe(5)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 54-62°. In the sixth Fe site, Fe(6) is bonded to one O(5), one O(9), two equivalent O(7), and two equivalent O(8) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Fe(5)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(4)O6 octahedra, and edges with two equivalent Fe(6)O6 octahedra. The corner-sharing octahedra are not tilted. In the seventh Fe site, Fe(7) is bonded to one O(3), two equivalent O(1), and three equivalent O(2) atoms to form FeO6 octahedra that share corners with four equivalent Fe(2)O6 octahedra,  a cornercorner with one Fe(5)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, edges with four equivalent Fe(2)O6 octahedra, and edges with four equivalent Fe(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 9-11°. Si(1) is bonded to one O(7), one O(8), and two equivalent O(6) atoms to form SiO4 tetrahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra, corners with four equivalent Fe(6)O6 octahedra, and corners with two equivalent Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 53-60°. There are ten inequivalent O sites. In the first O site, O(9) is bonded to one Fe(6), two equivalent Fe(4), and three equivalent Fe(1) atoms to form OFe6 octahedra that share corners with four equivalent O(10)Fe5 square pyramids, edges with four equivalent O(9)Fe6 octahedra, and edges with four equivalent O(10)Fe5 square pyramids. In the second O site, O(10) is bonded to two equivalent Fe(1) and three equivalent Fe(4) atoms to form OFe5 square pyramids that share corners with four equivalent O(9)Fe6 octahedra, edges with four equivalent O(9)Fe6 octahedra, and edges with four equivalent O(10)Fe5 square pyramids. The corner-sharing octahedral tilt angles are 3°. In the third O site, O(1) is bonded to one Fe(3), two equivalent Fe(7), and three equivalent Fe(2) atoms to form OFe6 octahedra that share corners with four equivalent O(2)Fe5 square pyramids,  a cornercorner with one O(4)Fe4 tetrahedra, edges with four equivalent O(1)Fe6 octahedra, edges with four equivalent O(2)Fe5 square pyramids, edges with two equivalent O(3)Fe4 tetrahedra, and edges with two equivalent O(4)Fe4 tetrahedra. In the fourth O site, O(2) is bonded to two equivalent Fe(2) and three equivalent Fe(7) atoms to form OFe5 square pyramids that share corners with four equivalent O(1)Fe6 octahedra, corners with two equivalent O(4)Fe4 tetrahedra, corners with three equivalent O(3)Fe4 tetrahedra, edges with four equivalent O(1)Fe6 octahedra, and edges with four equivalent O(2)Fe5 square pyramids. The corner-sharing octahedral tilt angles range from 9-11°. In the fifth O site, O(3) is bonded to one Fe(5), one Fe(7), and two equivalent Fe(3) atoms to form distorted OFe4 tetrahedra that share corners with three equivalent O(2)Fe5 square pyramids, corners with two equivalent O(3)Fe4 tetrahedra, corners with three equivalent O(4)Fe4 tetrahedra, edges with two equivalent O(1)Fe6 octahedra, and  an edgeedge with one O(4)Fe4 tetrahedra. In the sixth O site, O(4) is bonded to one Fe(2), one Fe(5), and two equivalent Fe(3) atoms to form distorted OFe4 tetrahedra that share  a cornercorner with one O(1)Fe6 octahedra, corners with two equivalent O(2)Fe5 square pyramids, corners with two equivalent O(4)Fe4 tetrahedra, corners with three equivalent O(3)Fe4 tetrahedra, edges with two equivalent O(1)Fe6 octahedra, and  an edgeedge with one O(3)Fe4 tetrahedra. The corner-sharing octahedral tilt angles are 2°. In the seventh O site, O(5) is bonded in a trigonal planar geometry to one Fe(6) and two equivalent Fe(5) atoms. In the eighth O site, O(6) is bonded in a trigonal planar geometry to one Fe(3) and two equivalent Si(1) atoms. In the ninth O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Fe(4), two equivalent Fe(6), and one Si(1) atom. In the tenth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Fe(1), two equivalent Fe(6), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe7SiO10
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.050
_cell_length_b   6.056
_cell_length_c   21.924
_cell_angle_alpha   82.201
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   401.196
_cell_formula_units_Z   2
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
  Fe  Fe0  1  0.250  0.846  0.552  1.0
  Fe  Fe1  1  0.750  0.344  0.055  1.0
  Fe  Fe2  1  0.750  0.455  0.839  1.0
  Fe  Fe3  1  0.250  0.545  0.161  1.0
  Fe  Fe4  1  0.250  0.360  0.554  1.0
  Fe  Fe5  1  0.750  0.640  0.446  1.0
  Fe  Fe6  1  0.250  0.656  0.945  1.0
  Fe  Fe7  1  0.750  0.154  0.448  1.0
  Fe  Fe8  1  0.250  0.974  0.804  1.0
  Fe  Fe9  1  0.750  0.026  0.196  1.0
  Fe  Fe10  1  0.750  0.044  0.659  1.0
  Fe  Fe11  1  0.250  0.956  0.341  1.0
  Fe  Fe12  1  0.750  0.853  0.053  1.0
  Fe  Fe13  1  0.250  0.147  0.947  1.0
  Si  Si14  1  0.750  0.468  0.309  1.0
  Si  Si15  1  0.250  0.532  0.691  1.0
  O  O16  1  0.750  0.383  0.954  1.0
  O  O17  1  0.250  0.617  0.046  1.0
  O  O18  1  0.750  0.911  0.956  1.0
  O  O19  1  0.250  0.089  0.044  1.0
  O  O20  1  0.250  0.212  0.854  1.0
  O  O21  1  0.750  0.788  0.146  1.0
  O  O22  1  0.250  0.683  0.850  1.0
  O  O23  1  0.750  0.317  0.150  1.0
  O  O24  1  0.750  0.005  0.753  1.0
  O  O25  1  0.250  0.995  0.247  1.0
  O  O26  1  0.750  0.509  0.731  1.0
  O  O27  1  0.250  0.491  0.269  1.0
  O  O28  1  0.250  0.323  0.651  1.0
  O  O29  1  0.750  0.677  0.349  1.0
  O  O30  1  0.250  0.784  0.654  1.0
  O  O31  1  0.750  0.216  0.346  1.0
  O  O32  1  0.750  0.094  0.561  1.0
  O  O33  1  0.250  0.906  0.439  1.0
  O  O34  1  0.250  0.382  0.459  1.0
  O  O35  1  0.750  0.618  0.541  1.0
[/CIF]
.