The crystal structure described by Ba2Mg(FeO2)4 crystallizes in the trigonal P312 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted q6 geometry to three equivalent O(3) and six equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded to three equivalent Mg(1), three equivalent O(2), and six equivalent O(1) atoms to form distorted BaMg3O9 cuboctahedra that share edges with six equivalent Ba(2)Mg3O9 cuboctahedra, edges with six equivalent Fe(2)MgO4 tetrahedra, and edges with six equivalent Fe(1)O4 tetrahedra. Mg(1) is bonded to three equivalent Ba(2) and two equivalent Fe(2) atoms to form corner-sharing MgBa3Fe2 trigonal bipyramids. 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  a cornercorner with one Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)MgO4 tetrahedra, and edges with three equivalent Ba(2)Mg3O9 cuboctahedra. In the second Fe site, Fe(2) is bonded to one Mg(1), one O(3), and three equivalent O(1) atoms to form distorted FeMgO4 tetrahedra that share corners with two equivalent Fe(2)MgO4 tetrahedra, corners with three equivalent Fe(1)O4 tetrahedra, and edges with three equivalent Ba(2)Mg3O9 cuboctahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a linear geometry to three equivalent Ba(2) and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a linear geometry to three equivalent Ba(1) and two equivalent Fe(2) atoms. is represented by the CIF card [CIF]
data_Ba2Mg(FeO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.603
_cell_length_b   5.603
_cell_length_c   9.311
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   253.184
_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
  Ba  Ba0  1  0.000  0.000  0.750  1.0
  Ba  Ba1  1  0.000  0.000  0.250  1.0
  Mg  Mg2  1  0.667  0.333  0.250  1.0
  Fe  Fe3  1  0.333  0.667  0.454  1.0
  Fe  Fe4  1  0.667  0.333  0.950  1.0
  Fe  Fe5  1  0.667  0.333  0.550  1.0
  Fe  Fe6  1  0.333  0.667  0.046  1.0
  O  O7  1  0.665  0.997  0.503  1.0
  O  O8  1  0.665  0.668  0.997  1.0
  O  O9  1  0.003  0.335  0.997  1.0
  O  O10  1  0.003  0.668  0.503  1.0
  O  O11  1  0.332  0.335  0.503  1.0
  O  O12  1  0.332  0.997  0.997  1.0
  O  O13  1  0.333  0.667  0.250  1.0
  O  O14  1  0.667  0.333  0.750  1.0
[/CIF]
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The crystal structure described by Ba2Mg(FeO2)4 crystallizes in the trigonal P312 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted q6 geometry to three equivalent O(3) and six equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded to three equivalent Mg(1), three equivalent O(2), and six equivalent O(1) atoms to form distorted BaMg3O9 cuboctahedra that share edges with six equivalent Ba(2)Mg3O9 cuboctahedra, edges with six equivalent Fe(2)MgO4 tetrahedra, and edges with six equivalent Fe(1)O4 tetrahedra. Mg(1) is bonded to three equivalent Ba(2) and two equivalent Fe(2) atoms to form corner-sharing MgBa3Fe2 trigonal bipyramids. 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  a cornercorner with one Fe(1)O4 tetrahedra, corners with three equivalent Fe(2)MgO4 tetrahedra, and edges with three equivalent Ba(2)Mg3O9 cuboctahedra. In the second Fe site, Fe(2) is bonded to one Mg(1), one O(3), and three equivalent O(1) atoms to form distorted FeMgO4 tetrahedra that share corners with two equivalent Fe(2)MgO4 tetrahedra, corners with three equivalent Fe(1)O4 tetrahedra, and edges with three equivalent Ba(2)Mg3O9 cuboctahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ba(1), one Ba(2), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a linear geometry to three equivalent Ba(2) and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a linear geometry to three equivalent Ba(1) and two equivalent Fe(2) atoms. is represented by the CIF card [CIF]
data_Ba2Mg(FeO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.603
_cell_length_b   5.603
_cell_length_c   9.311
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   253.184
_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
  Ba  Ba0  1  0.000  0.000  0.750  1.0
  Ba  Ba1  1  0.000  0.000  0.250  1.0
  Mg  Mg2  1  0.667  0.333  0.250  1.0
  Fe  Fe3  1  0.333  0.667  0.454  1.0
  Fe  Fe4  1  0.667  0.333  0.950  1.0
  Fe  Fe5  1  0.667  0.333  0.550  1.0
  Fe  Fe6  1  0.333  0.667  0.046  1.0
  O  O7  1  0.665  0.997  0.503  1.0
  O  O8  1  0.665  0.668  0.997  1.0
  O  O9  1  0.003  0.335  0.997  1.0
  O  O10  1  0.003  0.668  0.503  1.0
  O  O11  1  0.332  0.335  0.503  1.0
  O  O12  1  0.332  0.997  0.997  1.0
  O  O13  1  0.333  0.667  0.250  1.0
  O  O14  1  0.667  0.333  0.750  1.0
[/CIF]
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