The structure described by Mo4O9 crystallizes in the tetragonal P4/m space group. Mo(1) is bonded to one O(1), two equivalent O(2), and three equivalent O(3) atoms to form a mixture of corner and edge-sharing MoO6 octahedra. The corner-sharing octahedral tilt angles range from 0-21°. There are three inequivalent O sites. In the first O site, O(3) is bonded in a T-shaped geometry to three equivalent Mo(1) atoms. In the second O site, O(1) is bonded in a square co-planar geometry to four equivalent Mo(1) atoms. In the third O site, O(2) is bonded in a linear geometry to two equivalent Mo(1) atoms. is represented by the CIF card [CIF]
data_Mo4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.804
_cell_length_b   6.804
_cell_length_c   3.852
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   178.307
_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
  Mo  Mo0  1  0.627  0.804  0.500  1.0
  Mo  Mo1  1  0.196  0.627  0.500  1.0
  Mo  Mo2  1  0.373  0.196  0.500  1.0
  Mo  Mo3  1  0.804  0.373  0.500  1.0
  O  O4  1  0.500  0.500  0.500  1.0
  O  O5  1  0.800  0.370  0.000  1.0
  O  O6  1  0.370  0.200  0.000  1.0
  O  O7  1  0.630  0.800  0.000  1.0
  O  O8  1  0.200  0.630  0.000  1.0
  O  O9  1  0.106  0.338  0.500  1.0
  O  O10  1  0.338  0.894  0.500  1.0
  O  O11  1  0.662  0.106  0.500  1.0
  O  O12  1  0.894  0.662  0.500  1.0
[/CIF]
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The structure described by Mo4O9 crystallizes in the tetragonal P4/m space group. Mo(1) is bonded to one O(1), two equivalent O(2), and three equivalent O(3) atoms to form a mixture of corner and edge-sharing MoO6 octahedra. The corner-sharing octahedral tilt angles range from 0-21°. There are three inequivalent O sites. In the first O site, O(3) is bonded in a T-shaped geometry to three equivalent Mo(1) atoms. In the second O site, O(1) is bonded in a square co-planar geometry to four equivalent Mo(1) atoms. In the third O site, O(2) is bonded in a linear geometry to two equivalent Mo(1) atoms. is represented by the CIF card [CIF]
data_Mo4O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.804
_cell_length_b   6.804
_cell_length_c   3.852
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   178.307
_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
  Mo  Mo0  1  0.627  0.804  0.500  1.0
  Mo  Mo1  1  0.196  0.627  0.500  1.0
  Mo  Mo2  1  0.373  0.196  0.500  1.0
  Mo  Mo3  1  0.804  0.373  0.500  1.0
  O  O4  1  0.500  0.500  0.500  1.0
  O  O5  1  0.800  0.370  0.000  1.0
  O  O6  1  0.370  0.200  0.000  1.0
  O  O7  1  0.630  0.800  0.000  1.0
  O  O8  1  0.200  0.630  0.000  1.0
  O  O9  1  0.106  0.338  0.500  1.0
  O  O10  1  0.338  0.894  0.500  1.0
  O  O11  1  0.662  0.106  0.500  1.0
  O  O12  1  0.894  0.662  0.500  1.0
[/CIF]
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