The material described by Mg4FeO5 is Caswellsilverite-like structured and crystallizes in the monoclinic P2/m space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three O(2,2) and three O(3,3) atoms to form MgO6 octahedra that share corners with three equivalent Mg(2)O6 octahedra; corners with three equivalent Fe(1)O6 octahedra; edges with three Mg(2,2)O6 octahedra; edges with three Fe(1,1)O6 octahedra; and edges with six Mg(1,1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second Mg site, Mg(1) is bonded to three O(2,2) and three O(3,3) atoms to form MgO6 octahedra that share corners with three equivalent Mg(2)O6 octahedra; corners with three equivalent Fe(1)O6 octahedra; edges with three Mg(2,2)O6 octahedra; edges with three Fe(1,1)O6 octahedra; and edges with six Mg(1,1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the third Mg site, Mg(2) is bonded to three equivalent O(1) and three O(3,3) atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedra are not tilted. In the fourth Mg site, Mg(2) is bonded to three equivalent O(1) and three O(3,3) atoms to form a mixture of corner and edge-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 O(2,2) atoms to form FeO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra; edges with six Mg(1,1)O6 octahedra; and edges with six Fe(1,1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-5°. In the second Fe site, Fe(1) is bonded to six O(2,2) atoms to form FeO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra; edges with six Mg(1,1)O6 octahedra; and edges with six Fe(1,1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-4°. There are five inequivalent O sites. In the first O site, O(1) is bonded to six Mg(2,2) atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to three Mg(1,1) and three Fe(1,1) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra; corners with three equivalent O(3)Mg6 octahedra; edges with three O(3,3)Mg6 octahedra; and edges with nine O(2,2)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third O site, O(2) is bonded to three Mg(1,1) and three Fe(1,1) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra; corners with three equivalent O(3)Mg6 octahedra; edges with three O(3,3)Mg6 octahedra; and edges with nine O(2,2)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth O site, O(3) is bonded to three Mg(1,1) and three Mg(2,2) 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 O(2,2)Mg3Fe3 octahedra; edges with three equivalent O(1)Mg6 octahedra; and edges with six O(3,3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fifth O site, O(3) is bonded to three Mg(1,1) and three Mg(2,2) 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 O(2,2)Mg3Fe3 octahedra; edges with three equivalent O(1)Mg6 octahedra; and edges with six O(3,3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. is represented by the CIF file [CIF]
data_Mg4FeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.017
_cell_length_b   3.017
_cell_length_c   12.515
_cell_angle_alpha   96.030
_cell_angle_beta   96.033
_cell_angle_gamma   60.428
_symmetry_Int_Tables_number   1
_cell_volume   98.352
_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  0.000  1.0
  Mg  Mg1  1  0.592  0.592  0.796  1.0
  Mg  Mg2  1  0.408  0.408  0.204  1.0
  Mg  Mg3  1  0.197  0.197  0.599  1.0
  Mg  Mg4  1  0.803  0.803  0.401  1.0
  O  O5  1  0.500  0.500  0.500  1.0
  O  O6  1  0.717  0.717  0.107  1.0
  O  O7  1  0.283  0.283  0.893  1.0
  O  O8  1  0.106  0.106  0.302  1.0
  O  O9  1  0.894  0.894  0.698  1.0
[/CIF]
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The material described by Mg4FeO5 is Caswellsilverite-like structured and crystallizes in the monoclinic P2/m space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three O(2,2) and three O(3,3) atoms to form MgO6 octahedra that share corners with three equivalent Mg(2)O6 octahedra; corners with three equivalent Fe(1)O6 octahedra; edges with three Mg(2,2)O6 octahedra; edges with three Fe(1,1)O6 octahedra; and edges with six Mg(1,1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the second Mg site, Mg(1) is bonded to three O(2,2) and three O(3,3) atoms to form MgO6 octahedra that share corners with three equivalent Mg(2)O6 octahedra; corners with three equivalent Fe(1)O6 octahedra; edges with three Mg(2,2)O6 octahedra; edges with three Fe(1,1)O6 octahedra; and edges with six Mg(1,1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the third Mg site, Mg(2) is bonded to three equivalent O(1) and three O(3,3) atoms to form a mixture of corner and edge-sharing MgO6 octahedra. The corner-sharing octahedra are not tilted. In the fourth Mg site, Mg(2) is bonded to three equivalent O(1) and three O(3,3) atoms to form a mixture of corner and edge-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 O(2,2) atoms to form FeO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra; edges with six Mg(1,1)O6 octahedra; and edges with six Fe(1,1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-5°. In the second Fe site, Fe(1) is bonded to six O(2,2) atoms to form FeO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra; edges with six Mg(1,1)O6 octahedra; and edges with six Fe(1,1)O6 octahedra. The corner-sharing octahedral tilt angles range from 3-4°. There are five inequivalent O sites. In the first O site, O(1) is bonded to six Mg(2,2) atoms to form a mixture of corner and edge-sharing OMg6 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded to three Mg(1,1) and three Fe(1,1) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra; corners with three equivalent O(3)Mg6 octahedra; edges with three O(3,3)Mg6 octahedra; and edges with nine O(2,2)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the third O site, O(2) is bonded to three Mg(1,1) and three Fe(1,1) atoms to form OMg3Fe3 octahedra that share corners with three equivalent O(2)Mg3Fe3 octahedra; corners with three equivalent O(3)Mg6 octahedra; edges with three O(3,3)Mg6 octahedra; and edges with nine O(2,2)Mg3Fe3 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth O site, O(3) is bonded to three Mg(1,1) and three Mg(2,2) 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 O(2,2)Mg3Fe3 octahedra; edges with three equivalent O(1)Mg6 octahedra; and edges with six O(3,3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the fifth O site, O(3) is bonded to three Mg(1,1) and three Mg(2,2) 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 O(2,2)Mg3Fe3 octahedra; edges with three equivalent O(1)Mg6 octahedra; and edges with six O(3,3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. is represented by the CIF file [CIF]
data_Mg4FeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.017
_cell_length_b   3.017
_cell_length_c   12.515
_cell_angle_alpha   96.030
_cell_angle_beta   96.033
_cell_angle_gamma   60.428
_symmetry_Int_Tables_number   1
_cell_volume   98.352
_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  0.000  1.0
  Mg  Mg1  1  0.592  0.592  0.796  1.0
  Mg  Mg2  1  0.408  0.408  0.204  1.0
  Mg  Mg3  1  0.197  0.197  0.599  1.0
  Mg  Mg4  1  0.803  0.803  0.401  1.0
  O  O5  1  0.500  0.500  0.500  1.0
  O  O6  1  0.717  0.717  0.107  1.0
  O  O7  1  0.283  0.283  0.893  1.0
  O  O8  1  0.106  0.106  0.302  1.0
  O  O9  1  0.894  0.894  0.698  1.0
[/CIF]
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