The crystal structure described by Mg4FeO5 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form MgO6 octahedra that share corners with three equivalent Mg(3)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, edges with three equivalent Mg(3)O6 octahedra, edges with three equivalent Fe(2)O6 octahedra, and edges with six equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Mg site, Mg(2) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form MgO6 octahedra that share corners with three equivalent Mg(4)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, edges with three equivalent Mg(4)O6 octahedra, edges with three equivalent Fe(1)O6 octahedra, and edges with six equivalent Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the third Mg site, Mg(3) is bonded to three equivalent O(1) and three equivalent O(5) atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra are not tilted. In the fourth Mg site, Mg(4) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Mg(2)O6 octahedra, edges with six equivalent Mg(2)O6 octahedra, and edges with six equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the second Fe site, Fe(2) is bonded to six equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with six equivalent Mg(1)O6 octahedra, and edges with six equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are five inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Mg(3) and three equivalent Mg(4) atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to three equivalent Mg(2) and three equivalent Fe(1) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra, corners with three equivalent O(4)Mg6 octahedra, edges with three equivalent O(4)Mg6 octahedra, and edges with nine equivalent O(2)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third O site, O(3) is bonded to three equivalent Mg(1) and three equivalent Fe(2) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(3)Mg3Fe3 octahedra, corners with three equivalent O(5)Mg6 octahedra, edges with three equivalent O(5)Mg6 octahedra, and edges with nine equivalent O(3)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth O site, O(4) is bonded to three equivalent Mg(2) and three equivalent Mg(4) atoms to form OMg6 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra, corners with three equivalent O(1)Mg6 octahedra, edges with three equivalent O(2)Mg3Fe3 octahedra, edges with three equivalent O(1)Mg6 octahedra, and edges with six equivalent O(4)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fifth O site, O(5) is bonded to three equivalent Mg(1) and three equivalent Mg(3) atoms to form OMg6 octahedra that share corners with three equivalent O(3)Mg3Fe3 octahedra, corners with three equivalent O(1)Mg6 octahedra, edges with three equivalent O(3)Mg3Fe3 octahedra, edges with three equivalent O(1)Mg6 octahedra, and edges with six equivalent O(5)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. is represented by the CIF card [CIF]
data_Mg4FeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.966
_cell_length_b   2.970
_cell_length_c   12.378
_cell_angle_alpha   96.840
_cell_angle_beta   90.002
_cell_angle_gamma   60.048
_symmetry_Int_Tables_number   1
_cell_volume   93.573
_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
  Fe  Fe0  1  1.000  0.000  1.000  1.0
  Mg  Mg1  1  0.401  0.199  0.797  1.0
  Mg  Mg2  1  0.599  0.801  0.203  1.0
  Mg  Mg3  1  0.800  0.400  0.599  1.0
  Mg  Mg4  1  0.200  0.600  0.401  1.0
  O  O5  1  0.500  1.000  0.500  1.0
  O  O6  1  0.297  0.405  0.107  1.0
  O  O7  1  0.703  0.595  0.893  1.0
  O  O8  1  0.900  0.201  0.302  1.0
  O  O9  1  0.100  0.799  0.698  1.0
[/CIF]
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The crystal structure described by Mg4FeO5 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form MgO6 octahedra that share corners with three equivalent Mg(3)O6 octahedra, corners with three equivalent Fe(2)O6 octahedra, edges with three equivalent Mg(3)O6 octahedra, edges with three equivalent Fe(2)O6 octahedra, and edges with six equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Mg site, Mg(2) is bonded to three equivalent O(2) and three equivalent O(4) atoms to form MgO6 octahedra that share corners with three equivalent Mg(4)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, edges with three equivalent Mg(4)O6 octahedra, edges with three equivalent Fe(1)O6 octahedra, and edges with six equivalent Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the third Mg site, Mg(3) is bonded to three equivalent O(1) and three equivalent O(5) atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra are not tilted. In the fourth Mg site, Mg(4) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form a mixture of edge and corner-sharing MgO6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to six equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Mg(2)O6 octahedra, edges with six equivalent Mg(2)O6 octahedra, and edges with six equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 3°. In the second Fe site, Fe(2) is bonded to six equivalent O(3) atoms to form FeO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with six equivalent Mg(1)O6 octahedra, and edges with six equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles are 3°. There are five inequivalent O sites. In the first O site, O(1) is bonded to three equivalent Mg(3) and three equivalent Mg(4) atoms to form a mixture of edge and corner-sharing OMg6 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to three equivalent Mg(2) and three equivalent Fe(1) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra, corners with three equivalent O(4)Mg6 octahedra, edges with three equivalent O(4)Mg6 octahedra, and edges with nine equivalent O(2)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third O site, O(3) is bonded to three equivalent Mg(1) and three equivalent Fe(2) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(3)Mg3Fe3 octahedra, corners with three equivalent O(5)Mg6 octahedra, edges with three equivalent O(5)Mg6 octahedra, and edges with nine equivalent O(3)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth O site, O(4) is bonded to three equivalent Mg(2) and three equivalent Mg(4) atoms to form OMg6 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra, corners with three equivalent O(1)Mg6 octahedra, edges with three equivalent O(2)Mg3Fe3 octahedra, edges with three equivalent O(1)Mg6 octahedra, and edges with six equivalent O(4)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fifth O site, O(5) is bonded to three equivalent Mg(1) and three equivalent Mg(3) atoms to form OMg6 octahedra that share corners with three equivalent O(3)Mg3Fe3 octahedra, corners with three equivalent O(1)Mg6 octahedra, edges with three equivalent O(3)Mg3Fe3 octahedra, edges with three equivalent O(1)Mg6 octahedra, and edges with six equivalent O(5)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. is represented by the CIF card [CIF]
data_Mg4FeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.966
_cell_length_b   2.970
_cell_length_c   12.378
_cell_angle_alpha   96.840
_cell_angle_beta   90.002
_cell_angle_gamma   60.048
_symmetry_Int_Tables_number   1
_cell_volume   93.573
_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
  Fe  Fe0  1  1.000  0.000  1.000  1.0
  Mg  Mg1  1  0.401  0.199  0.797  1.0
  Mg  Mg2  1  0.599  0.801  0.203  1.0
  Mg  Mg3  1  0.800  0.400  0.599  1.0
  Mg  Mg4  1  0.200  0.600  0.401  1.0
  O  O5  1  0.500  1.000  0.500  1.0
  O  O6  1  0.297  0.405  0.107  1.0
  O  O7  1  0.703  0.595  0.893  1.0
  O  O8  1  0.900  0.201  0.302  1.0
  O  O9  1  0.100  0.799  0.698  1.0
[/CIF]
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