The compound described by MgMn4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with four equivalent Mn(3)O6 octahedra,  an edgeedge with one Mn(1)O4 tetrahedra, and faces with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form distorted MnO4 tetrahedra that share corners with six equivalent Mn(3)O6 octahedra and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-66°. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the third Mn site, Mn(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Mn(1)O4 tetrahedra, edges with two equivalent Mn(3)O6 octahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. Ni(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mn(1), one Mn(2), one Mn(3), and two equivalent Ni(1) atoms to form distorted OMn3Ni2 trigonal bipyramids that share corners with five equivalent O(4)MgMnNi2 tetrahedra,  a cornercorner with one O(1)Mn3Ni2 trigonal bipyramid, corners with two equivalent O(2)MgMn3Ni trigonal bipyramids, edges with two equivalent O(2)MgMn3Ni trigonal bipyramids, and  a faceface with one O(1)Mn3Ni2 trigonal bipyramid. In the second O site, O(2) is bonded to one Mg(1), one Mn(2), two equivalent Mn(3), and one Ni(1) atom to form distorted OMgMn3Ni trigonal bipyramids that share corners with two equivalent O(4)MgMnNi2 tetrahedra,  a cornercorner with one O(2)MgMn3Ni trigonal bipyramid, corners with two equivalent O(1)Mn3Ni2 trigonal bipyramids, edges with two equivalent O(4)MgMnNi2 tetrahedra, edges with two equivalent O(1)Mn3Ni2 trigonal bipyramids, and  a faceface with one O(2)MgMn3Ni trigonal bipyramid. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Mn(1), one Mn(2), and two equivalent Mn(3) atoms. In the fourth O site, O(4) is bonded to one Mg(1), one Mn(3), and two equivalent Ni(1) atoms to form distorted OMgMnNi2 tetrahedra that share  a cornercorner with one O(4)MgMnNi2 tetrahedra, corners with two equivalent O(2)MgMn3Ni trigonal bipyramids, corners with five equivalent O(1)Mn3Ni2 trigonal bipyramids,  an edgeedge with one O(4)MgMnNi2 tetrahedra, and edges with two equivalent O(2)MgMn3Ni trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.178
_cell_length_b   6.178
_cell_length_c   6.614
_cell_angle_alpha   57.634
_cell_angle_beta   57.634
_cell_angle_gamma   59.465
_symmetry_Int_Tables_number   1
_cell_volume   171.184
_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
  Mg  Mg0  1  0.854  0.854  0.146  1.0
  Mn  Mn1  1  0.173  0.173  0.827  1.0
  Mn  Mn2  1  0.277  0.277  0.223  1.0
  Mn  Mn3  1  0.594  0.594  0.143  1.0
  Mn  Mn4  1  0.594  0.594  0.670  1.0
  Ni  Ni5  1  0.123  0.680  0.599  1.0
  Ni  Ni6  1  0.680  0.123  0.599  1.0
  O  O7  1  0.369  0.369  0.433  1.0
  O  O8  1  0.417  0.855  0.364  1.0
  O  O9  1  0.369  0.369  0.830  1.0
  O  O10  1  0.855  0.417  0.364  1.0
  O  O11  1  0.304  0.771  0.962  1.0
  O  O12  1  0.825  0.825  0.476  1.0
  O  O13  1  0.771  0.304  0.962  1.0
  O  O14  1  0.825  0.825  0.875  1.0
[/CIF]
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The compound described by MgMn4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted MgO6 octahedra that share corners with four equivalent Mn(3)O6 octahedra,  an edgeedge with one Mn(1)O4 tetrahedra, and faces with two equivalent Mn(3)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form distorted MnO4 tetrahedra that share corners with six equivalent Mn(3)O6 octahedra and  an edgeedge with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 26-66°. In the second Mn site, Mn(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. In the third Mn site, Mn(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with three equivalent Mn(1)O4 tetrahedra, edges with two equivalent Mn(3)O6 octahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. Ni(1) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(1), and two equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mn(1), one Mn(2), one Mn(3), and two equivalent Ni(1) atoms to form distorted OMn3Ni2 trigonal bipyramids that share corners with five equivalent O(4)MgMnNi2 tetrahedra,  a cornercorner with one O(1)Mn3Ni2 trigonal bipyramid, corners with two equivalent O(2)MgMn3Ni trigonal bipyramids, edges with two equivalent O(2)MgMn3Ni trigonal bipyramids, and  a faceface with one O(1)Mn3Ni2 trigonal bipyramid. In the second O site, O(2) is bonded to one Mg(1), one Mn(2), two equivalent Mn(3), and one Ni(1) atom to form distorted OMgMn3Ni trigonal bipyramids that share corners with two equivalent O(4)MgMnNi2 tetrahedra,  a cornercorner with one O(2)MgMn3Ni trigonal bipyramid, corners with two equivalent O(1)Mn3Ni2 trigonal bipyramids, edges with two equivalent O(4)MgMnNi2 tetrahedra, edges with two equivalent O(1)Mn3Ni2 trigonal bipyramids, and  a faceface with one O(2)MgMn3Ni trigonal bipyramid. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mg(1), one Mn(1), one Mn(2), and two equivalent Mn(3) atoms. In the fourth O site, O(4) is bonded to one Mg(1), one Mn(3), and two equivalent Ni(1) atoms to form distorted OMgMnNi2 tetrahedra that share  a cornercorner with one O(4)MgMnNi2 tetrahedra, corners with two equivalent O(2)MgMn3Ni trigonal bipyramids, corners with five equivalent O(1)Mn3Ni2 trigonal bipyramids,  an edgeedge with one O(4)MgMnNi2 tetrahedra, and edges with two equivalent O(2)MgMn3Ni trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.178
_cell_length_b   6.178
_cell_length_c   6.614
_cell_angle_alpha   57.634
_cell_angle_beta   57.634
_cell_angle_gamma   59.465
_symmetry_Int_Tables_number   1
_cell_volume   171.184
_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
  Mg  Mg0  1  0.854  0.854  0.146  1.0
  Mn  Mn1  1  0.173  0.173  0.827  1.0
  Mn  Mn2  1  0.277  0.277  0.223  1.0
  Mn  Mn3  1  0.594  0.594  0.143  1.0
  Mn  Mn4  1  0.594  0.594  0.670  1.0
  Ni  Ni5  1  0.123  0.680  0.599  1.0
  Ni  Ni6  1  0.680  0.123  0.599  1.0
  O  O7  1  0.369  0.369  0.433  1.0
  O  O8  1  0.417  0.855  0.364  1.0
  O  O9  1  0.369  0.369  0.830  1.0
  O  O10  1  0.855  0.417  0.364  1.0
  O  O11  1  0.304  0.771  0.962  1.0
  O  O12  1  0.825  0.825  0.476  1.0
  O  O13  1  0.771  0.304  0.962  1.0
  O  O14  1  0.825  0.825  0.875  1.0
[/CIF]
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