The structure described by MgMn4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form distorted MgO4 tetrahedra that share corners with six equivalent Mn(3)O6 octahedra and corners with two equivalent Mn(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 29-61°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form MnO4 tetrahedra that share corners with six equivalent Mn(3)O6 octahedra and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-77°. 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 three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Mn(1)O4 tetrahedra, and edges with two equivalent Mn(3)O6 octahedra. Ni(1) is bonded in a 5-coordinate geometry to one O(3), 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(2), one Mn(3), and two equivalent Ni(1) atoms to form OMn2Ni2 tetrahedra that share  a cornercorner with one O(1)Mn2Ni2 tetrahedra, corners with five equivalent O(4)MgMn2Ni2 trigonal bipyramids, and  an edgeedge with one O(1)Mn2Ni2 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(2), and two equivalent Mn(3) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mn(1), one Mn(2), two equivalent Mn(3), and one Ni(1) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Mn(1), one Mn(3), and two equivalent Ni(1) atoms to form distorted OMgMn2Ni2 trigonal bipyramids that share corners with five equivalent O(1)Mn2Ni2 tetrahedra,  a cornercorner with one O(4)MgMn2Ni2 trigonal bipyramid, and  a faceface with one O(4)MgMn2Ni2 trigonal bipyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.190
_cell_length_b   6.190
_cell_length_c   6.534
_cell_angle_alpha   58.145
_cell_angle_beta   58.145
_cell_angle_gamma   59.507
_symmetry_Int_Tables_number   1
_cell_volume   171.310
_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  0.018  0.018  0.482  1.0
  Mn  Mn1  1  0.937  0.937  0.063  1.0
  Mn  Mn2  1  0.332  0.332  0.168  1.0
  Mn  Mn3  1  0.609  0.609  0.152  1.0
  Mn  Mn4  1  0.609  0.609  0.629  1.0
  Ni  Ni5  1  0.084  0.530  0.693  1.0
  Ni  Ni6  1  0.530  0.084  0.693  1.0
  O  O7  1  0.383  0.383  0.417  1.0
  O  O8  1  0.407  0.881  0.356  1.0
  O  O9  1  0.383  0.383  0.816  1.0
  O  O10  1  0.881  0.407  0.356  1.0
  O  O11  1  0.355  0.800  0.922  1.0
  O  O12  1  0.835  0.835  0.462  1.0
  O  O13  1  0.800  0.355  0.922  1.0
  O  O14  1  0.835  0.835  0.867  1.0
[/CIF]
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The structure described by MgMn4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(2) and two equivalent O(4) atoms to form distorted MgO4 tetrahedra that share corners with six equivalent Mn(3)O6 octahedra and corners with two equivalent Mn(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 29-61°. There are three inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(3) and two equivalent O(4) atoms to form MnO4 tetrahedra that share corners with six equivalent Mn(3)O6 octahedra and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 55-77°. 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 three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Mn(1)O4 tetrahedra, and edges with two equivalent Mn(3)O6 octahedra. Ni(1) is bonded in a 5-coordinate geometry to one O(3), 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(2), one Mn(3), and two equivalent Ni(1) atoms to form OMn2Ni2 tetrahedra that share  a cornercorner with one O(1)Mn2Ni2 tetrahedra, corners with five equivalent O(4)MgMn2Ni2 trigonal bipyramids, and  an edgeedge with one O(1)Mn2Ni2 tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Mn(2), and two equivalent Mn(3) atoms. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Mn(1), one Mn(2), two equivalent Mn(3), and one Ni(1) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Mn(1), one Mn(3), and two equivalent Ni(1) atoms to form distorted OMgMn2Ni2 trigonal bipyramids that share corners with five equivalent O(1)Mn2Ni2 tetrahedra,  a cornercorner with one O(4)MgMn2Ni2 trigonal bipyramid, and  a faceface with one O(4)MgMn2Ni2 trigonal bipyramid. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgMn4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.190
_cell_length_b   6.190
_cell_length_c   6.534
_cell_angle_alpha   58.145
_cell_angle_beta   58.145
_cell_angle_gamma   59.507
_symmetry_Int_Tables_number   1
_cell_volume   171.310
_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  0.018  0.018  0.482  1.0
  Mn  Mn1  1  0.937  0.937  0.063  1.0
  Mn  Mn2  1  0.332  0.332  0.168  1.0
  Mn  Mn3  1  0.609  0.609  0.152  1.0
  Mn  Mn4  1  0.609  0.609  0.629  1.0
  Ni  Ni5  1  0.084  0.530  0.693  1.0
  Ni  Ni6  1  0.530  0.084  0.693  1.0
  O  O7  1  0.383  0.383  0.417  1.0
  O  O8  1  0.407  0.881  0.356  1.0
  O  O9  1  0.383  0.383  0.816  1.0
  O  O10  1  0.881  0.407  0.356  1.0
  O  O11  1  0.355  0.800  0.922  1.0
  O  O12  1  0.835  0.835  0.462  1.0
  O  O13  1  0.800  0.355  0.922  1.0
  O  O14  1  0.835  0.835  0.867  1.0
[/CIF]
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