The crystal structure described by Fe2Mo4O7 crystallizes in the monoclinic Cm space group. There are six inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form MoO5 square pyramids that share  a cornercorner with one Fe(2)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra,  an edgeedge with one Fe(3)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and edges with two equivalent Mo(1)O5 square pyramids. In the second Mo site, Mo(2) is bonded to one O(1), one O(10), one O(4), one O(5), and one O(7) atom to form MoO5 square pyramids that share  a cornercorner with one Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra,  an edgeedge with one Fe(3)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and edges with two equivalent Mo(2)O5 square pyramids. In the third Mo site, Mo(3) is bonded in a rectangular see-saw-like geometry to one O(10), one O(6), and two equivalent O(11) atoms. In the fourth Mo site, Mo(4) is bonded in a rectangular see-saw-like geometry to one O(5), one O(9), and two equivalent O(11) atoms. In the fifth Mo site, Mo(5) is bonded in a rectangular see-saw-like geometry to one O(4), one O(8), and two equivalent O(11) atoms. In the sixth Mo site, Mo(6) is bonded in a rectangular see-saw-like geometry to one O(3), one O(7), and two equivalent O(11) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(8), one O(9), and two equivalent O(1) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, corners with two equivalent Mo(2)O5 square pyramids, and corners with four equivalent Mo(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 56-57°. In the second Fe site, Fe(2) is bonded to one O(10), one O(7), and two equivalent O(2) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, corners with two equivalent Mo(1)O5 square pyramids, and corners with four equivalent Mo(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 55-56°. In the third Fe site, Fe(3) is bonded to one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, edges with two equivalent Fe(4)O6 octahedra, edges with two equivalent Mo(1)O5 square pyramids, and edges with two equivalent Mo(2)O5 square pyramids. In the fourth Fe site, Fe(4) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Mo(1)O5 square pyramids, and edges with two equivalent Mo(2)O5 square pyramids. There are eleven inequivalent O sites. In the first O site, O(1) is bonded to one Mo(2), one Fe(1), one Fe(3), and one Fe(4) atom to form a mixture of distorted corner and edge-sharing OFe3Mo trigonal pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mo(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mo(6), two equivalent Mo(1), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mo(5), two equivalent Mo(2), and one Fe(4) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mo(4), two equivalent Mo(2), and one Fe(3) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Mo(3), two equivalent Mo(1), and one Fe(3) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mo(6), two equivalent Mo(2), and one Fe(2) atom. In the eighth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Mo(5), two equivalent Mo(1), and one Fe(1) atom. In the ninth O site, O(9) is bonded in a rectangular see-saw-like geometry to one Mo(4), two equivalent Mo(1), and one Fe(1) atom. In the tenth O site, O(10) is bonded in a rectangular see-saw-like geometry to one Mo(3), two equivalent Mo(2), and one Fe(2) atom. In the eleventh O site, O(11) is bonded in a rectangular see-saw-like geometry to one Mo(3), one Mo(4), one Mo(5), and one Mo(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe2Mo4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.628
_cell_length_b   9.628
_cell_length_c   6.247
_cell_angle_alpha   71.289
_cell_angle_beta   71.289
_cell_angle_gamma   38.640
_symmetry_Int_Tables_number   1
_cell_volume   340.108
_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  0.554  0.554  0.701  1.0
  Fe  Fe1  1  0.446  0.446  0.309  1.0
  Fe  Fe2  1  0.002  0.002  0.002  1.0
  Fe  Fe3  1  0.001  0.001  0.508  1.0
  Mo  Mo4  1  0.385  0.881  0.121  1.0
  Mo  Mo5  1  0.881  0.385  0.121  1.0
  Mo  Mo6  1  0.620  0.121  0.885  1.0
  Mo  Mo7  1  0.121  0.620  0.885  1.0
  Mo  Mo8  1  0.250  0.250  0.730  1.0
  Mo  Mo9  1  0.751  0.751  0.247  1.0
  Mo  Mo10  1  0.752  0.752  0.721  1.0
  Mo  Mo11  1  0.251  0.251  0.248  1.0
  O  O12  1  0.224  0.761  0.765  1.0
  O  O13  1  0.247  0.767  0.252  1.0
  O  O14  1  0.767  0.247  0.252  1.0
  O  O15  1  0.761  0.224  0.765  1.0
  O  O16  1  0.128  0.128  0.349  1.0
  O  O17  1  0.873  0.873  0.657  1.0
  O  O18  1  0.875  0.875  0.103  1.0
  O  O19  1  0.130  0.130  0.899  1.0
  O  O20  1  0.378  0.378  0.124  1.0
  O  O21  1  0.629  0.629  0.891  1.0
  O  O22  1  0.627  0.627  0.363  1.0
  O  O23  1  0.375  0.375  0.630  1.0
  O  O24  1  0.500  0.008  0.482  1.0
  O  O25  1  0.008  0.500  0.482  1.0
[/CIF]
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The crystal structure described by Fe2Mo4O7 crystallizes in the monoclinic Cm space group. There are six inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form MoO5 square pyramids that share  a cornercorner with one Fe(2)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra,  an edgeedge with one Fe(3)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and edges with two equivalent Mo(1)O5 square pyramids. In the second Mo site, Mo(2) is bonded to one O(1), one O(10), one O(4), one O(5), and one O(7) atom to form MoO5 square pyramids that share  a cornercorner with one Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra,  an edgeedge with one Fe(3)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and edges with two equivalent Mo(2)O5 square pyramids. In the third Mo site, Mo(3) is bonded in a rectangular see-saw-like geometry to one O(10), one O(6), and two equivalent O(11) atoms. In the fourth Mo site, Mo(4) is bonded in a rectangular see-saw-like geometry to one O(5), one O(9), and two equivalent O(11) atoms. In the fifth Mo site, Mo(5) is bonded in a rectangular see-saw-like geometry to one O(4), one O(8), and two equivalent O(11) atoms. In the sixth Mo site, Mo(6) is bonded in a rectangular see-saw-like geometry to one O(3), one O(7), and two equivalent O(11) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(8), one O(9), and two equivalent O(1) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, corners with two equivalent Mo(2)O5 square pyramids, and corners with four equivalent Mo(1)O5 square pyramids. The corner-sharing octahedral tilt angles range from 56-57°. In the second Fe site, Fe(2) is bonded to one O(10), one O(7), and two equivalent O(2) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, corners with two equivalent Mo(1)O5 square pyramids, and corners with four equivalent Mo(2)O5 square pyramids. The corner-sharing octahedral tilt angles range from 55-56°. In the third Fe site, Fe(3) is bonded to one O(5), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, edges with two equivalent Fe(4)O6 octahedra, edges with two equivalent Mo(1)O5 square pyramids, and edges with two equivalent Mo(2)O5 square pyramids. In the fourth Fe site, Fe(4) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(2)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, edges with two equivalent Mo(1)O5 square pyramids, and edges with two equivalent Mo(2)O5 square pyramids. There are eleven inequivalent O sites. In the first O site, O(1) is bonded to one Mo(2), one Fe(1), one Fe(3), and one Fe(4) atom to form a mixture of distorted corner and edge-sharing OFe3Mo trigonal pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mo(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mo(6), two equivalent Mo(1), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mo(5), two equivalent Mo(2), and one Fe(4) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mo(4), two equivalent Mo(2), and one Fe(3) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Mo(3), two equivalent Mo(1), and one Fe(3) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mo(6), two equivalent Mo(2), and one Fe(2) atom. In the eighth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Mo(5), two equivalent Mo(1), and one Fe(1) atom. In the ninth O site, O(9) is bonded in a rectangular see-saw-like geometry to one Mo(4), two equivalent Mo(1), and one Fe(1) atom. In the tenth O site, O(10) is bonded in a rectangular see-saw-like geometry to one Mo(3), two equivalent Mo(2), and one Fe(2) atom. In the eleventh O site, O(11) is bonded in a rectangular see-saw-like geometry to one Mo(3), one Mo(4), one Mo(5), and one Mo(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Fe2Mo4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.628
_cell_length_b   9.628
_cell_length_c   6.247
_cell_angle_alpha   71.289
_cell_angle_beta   71.289
_cell_angle_gamma   38.640
_symmetry_Int_Tables_number   1
_cell_volume   340.108
_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  0.554  0.554  0.701  1.0
  Fe  Fe1  1  0.446  0.446  0.309  1.0
  Fe  Fe2  1  0.002  0.002  0.002  1.0
  Fe  Fe3  1  0.001  0.001  0.508  1.0
  Mo  Mo4  1  0.385  0.881  0.121  1.0
  Mo  Mo5  1  0.881  0.385  0.121  1.0
  Mo  Mo6  1  0.620  0.121  0.885  1.0
  Mo  Mo7  1  0.121  0.620  0.885  1.0
  Mo  Mo8  1  0.250  0.250  0.730  1.0
  Mo  Mo9  1  0.751  0.751  0.247  1.0
  Mo  Mo10  1  0.752  0.752  0.721  1.0
  Mo  Mo11  1  0.251  0.251  0.248  1.0
  O  O12  1  0.224  0.761  0.765  1.0
  O  O13  1  0.247  0.767  0.252  1.0
  O  O14  1  0.767  0.247  0.252  1.0
  O  O15  1  0.761  0.224  0.765  1.0
  O  O16  1  0.128  0.128  0.349  1.0
  O  O17  1  0.873  0.873  0.657  1.0
  O  O18  1  0.875  0.875  0.103  1.0
  O  O19  1  0.130  0.130  0.899  1.0
  O  O20  1  0.378  0.378  0.124  1.0
  O  O21  1  0.629  0.629  0.891  1.0
  O  O22  1  0.627  0.627  0.363  1.0
  O  O23  1  0.375  0.375  0.630  1.0
  O  O24  1  0.500  0.008  0.482  1.0
  O  O25  1  0.008  0.500  0.482  1.0
[/CIF]
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