The crystal structure described by MgNbMnO4 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with four equivalent Mg(1)O6 octahedra, edges with four equivalent Nb(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. Nb(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, edges with four equivalent Mg(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 7°. Mn(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with four equivalent Mg(1)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a square co-planar geometry to one Mg(1), two equivalent Nb(1), and one Mn(1) atom. In the second O site, O(2) is bonded to two equivalent Mg(1), one Nb(1), and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing OMg2Mn2Nb square pyramids. In the third O site, O(3) is bonded in a square co-planar geometry to one Mg(1), two equivalent Nb(1), and one Mn(1) atom. In the fourth O site, O(4) is bonded to two equivalent Mg(1), one Nb(1), and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing OMg2Mn2Nb square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMnNbO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.587
_cell_length_b   5.587
_cell_length_c   5.587
_cell_angle_alpha   136.171
_cell_angle_beta   136.122
_cell_angle_gamma   63.754
_symmetry_Int_Tables_number   1
_cell_volume   82.620
_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  0.250  0.750  0.500  1.0
  Mn  Mn1  1  0.749  0.249  0.500  1.0
  Nb  Nb2  1  0.000  0.000  0.000  1.0
  O  O3  1  0.487  0.987  0.500  1.0
  O  O4  1  0.225  0.225  0.000  1.0
  O  O5  1  0.013  0.513  0.500  1.0
  O  O6  1  0.775  0.775  0.000  1.0
[/CIF]
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The crystal structure described by MgNbMnO4 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with two equivalent Mn(1)O6 octahedra, corners with four equivalent Mg(1)O6 octahedra, edges with four equivalent Nb(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-13°. Nb(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(3) atoms to form NbO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, edges with four equivalent Mg(1)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles are 7°. Mn(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with four equivalent Mn(1)O6 octahedra, edges with four equivalent Mg(1)O6 octahedra, and edges with four equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-14°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a square co-planar geometry to one Mg(1), two equivalent Nb(1), and one Mn(1) atom. In the second O site, O(2) is bonded to two equivalent Mg(1), one Nb(1), and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing OMg2Mn2Nb square pyramids. In the third O site, O(3) is bonded in a square co-planar geometry to one Mg(1), two equivalent Nb(1), and one Mn(1) atom. In the fourth O site, O(4) is bonded to two equivalent Mg(1), one Nb(1), and two equivalent Mn(1) atoms to form a mixture of corner and edge-sharing OMg2Mn2Nb square pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMnNbO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.587
_cell_length_b   5.587
_cell_length_c   5.587
_cell_angle_alpha   136.171
_cell_angle_beta   136.122
_cell_angle_gamma   63.754
_symmetry_Int_Tables_number   1
_cell_volume   82.620
_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  0.250  0.750  0.500  1.0
  Mn  Mn1  1  0.749  0.249  0.500  1.0
  Nb  Nb2  1  0.000  0.000  0.000  1.0
  O  O3  1  0.487  0.987  0.500  1.0
  O  O4  1  0.225  0.225  0.000  1.0
  O  O5  1  0.013  0.513  0.500  1.0
  O  O6  1  0.775  0.775  0.000  1.0
[/CIF]
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