The crystal structure described by Mg3Fe3O8 is Spinel-like structured and crystallizes in the trigonal R-3m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with four equivalent Mg(1)O6 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2) and three equivalent O(1) atoms to form FeO4 tetrahedra that share corners with three equivalent Fe(2)O6 octahedra and corners with nine equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 57°. In the second Fe site, Fe(2) is bonded to six equivalent O(1) atoms to form FeO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra and edges with six equivalent Mg(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Mg(1) and one Fe(1) atom. is represented by the CIF card [CIF]
data_Mg3Fe3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.009
_cell_length_b   6.009
_cell_length_c   6.009
_cell_angle_alpha   59.781
_cell_angle_beta   59.781
_cell_angle_gamma   59.781
_symmetry_Int_Tables_number   1
_cell_volume   152.677
_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
  Mg  Mg0  1  0.000  0.000  0.500  1.0
  Mg  Mg1  1  0.000  0.500  0.000  1.0
  Mg  Mg2  1  0.500  0.000  0.000  1.0
  Fe  Fe3  1  0.368  0.368  0.368  1.0
  Fe  Fe4  1  0.632  0.632  0.632  1.0
  Fe  Fe5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.233  0.762  0.762  1.0
  O  O7  1  0.758  0.758  0.758  1.0
  O  O8  1  0.762  0.762  0.233  1.0
  O  O9  1  0.762  0.233  0.762  1.0
  O  O10  1  0.238  0.238  0.767  1.0
  O  O11  1  0.238  0.767  0.238  1.0
  O  O12  1  0.767  0.238  0.238  1.0
  O  O13  1  0.242  0.242  0.242  1.0
[/CIF]
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The crystal structure described by Mg3Fe3O8 is Spinel-like structured and crystallizes in the trigonal R-3m space group. Mg(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with four equivalent Mg(1)O6 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(2) and three equivalent O(1) atoms to form FeO4 tetrahedra that share corners with three equivalent Fe(2)O6 octahedra and corners with nine equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 57°. In the second Fe site, Fe(2) is bonded to six equivalent O(1) atoms to form FeO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra and edges with six equivalent Mg(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Mg(1) and one Fe(1) atom. is represented by the CIF card [CIF]
data_Mg3Fe3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.009
_cell_length_b   6.009
_cell_length_c   6.009
_cell_angle_alpha   59.781
_cell_angle_beta   59.781
_cell_angle_gamma   59.781
_symmetry_Int_Tables_number   1
_cell_volume   152.677
_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
  Mg  Mg0  1  0.000  0.000  0.500  1.0
  Mg  Mg1  1  0.000  0.500  0.000  1.0
  Mg  Mg2  1  0.500  0.000  0.000  1.0
  Fe  Fe3  1  0.368  0.368  0.368  1.0
  Fe  Fe4  1  0.632  0.632  0.632  1.0
  Fe  Fe5  1  0.000  0.000  0.000  1.0
  O  O6  1  0.233  0.762  0.762  1.0
  O  O7  1  0.758  0.758  0.758  1.0
  O  O8  1  0.762  0.762  0.233  1.0
  O  O9  1  0.762  0.233  0.762  1.0
  O  O10  1  0.238  0.238  0.767  1.0
  O  O11  1  0.238  0.767  0.238  1.0
  O  O12  1  0.767  0.238  0.238  1.0
  O  O13  1  0.242  0.242  0.242  1.0
[/CIF]
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