The compound described by MgFe4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form distorted MgO4 tetrahedra that share corners with six equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(2)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-62°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share corners with four equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(2)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and faces with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. In the second Fe site, Fe(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with six equivalent Fe(3)O6 octahedra, and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 54-88°. In the third Fe site, Fe(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, and  a faceface with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. 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 Mg(1), one Fe(2), one Fe(3), and two equivalent Ni(1) atoms to form distorted OMgFe2Ni2 trigonal bipyramids that share corners with five equivalent O(4)Fe2Ni2 tetrahedra,  a cornercorner with one O(1)MgFe2Ni2 trigonal bipyramid, and  a faceface with one O(1)MgFe2Ni2 trigonal bipyramid. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Fe(1), one Fe(2), two equivalent Fe(3), and one Ni(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), and two equivalent Fe(3) atoms. In the fourth O site, O(4) is bonded to one Fe(1), one Fe(3), and two equivalent Ni(1) atoms to form OFe2Ni2 tetrahedra that share  a cornercorner with one O(4)Fe2Ni2 tetrahedra, corners with five equivalent O(1)MgFe2Ni2 trigonal bipyramids, and  an edgeedge with one O(4)Fe2Ni2 tetrahedra. is represented by the CIF card [CIF]
data_MgFe4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.153
_cell_length_b   6.392
_cell_length_c   6.153
_cell_angle_alpha   58.708
_cell_angle_beta   59.301
_cell_angle_gamma   58.708
_symmetry_Int_Tables_number   1
_cell_volume   166.854
_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  0.204  0.796  0.204  1.0
  Fe  Fe1  1  0.892  0.108  0.892  1.0
  Fe  Fe2  1  0.292  0.208  0.292  1.0
  Fe  Fe3  1  0.628  0.087  0.628  1.0
  Fe  Fe4  1  0.628  0.658  0.628  1.0
  Ni  Ni5  1  0.160  0.568  0.704  1.0
  Ni  Ni6  1  0.704  0.568  0.160  1.0
  O  O7  1  0.383  0.407  0.383  1.0
  O  O8  1  0.428  0.336  0.901  1.0
  O  O9  1  0.383  0.827  0.383  1.0
  O  O10  1  0.901  0.336  0.428  1.0
  O  O11  1  0.339  0.923  0.815  1.0
  O  O12  1  0.861  0.439  0.861  1.0
  O  O13  1  0.815  0.923  0.339  1.0
  O  O14  1  0.861  0.838  0.861  1.0
[/CIF]
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The compound described by MgFe4(NiO4)2 crystallizes in the orthorhombic Imm2 space group. Mg(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form distorted MgO4 tetrahedra that share corners with six equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(2)O4 tetrahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 28-62°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted FeO6 octahedra that share corners with four equivalent Fe(3)O6 octahedra, corners with two equivalent Fe(2)O4 tetrahedra,  an edgeedge with one Mg(1)O4 tetrahedra, and faces with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. In the second Fe site, Fe(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form FeO4 tetrahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with six equivalent Fe(3)O6 octahedra, and corners with two equivalent Mg(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 54-88°. In the third Fe site, Fe(3) is bonded to one O(1), one O(4), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share corners with two equivalent Fe(1)O6 octahedra, corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Fe(2)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, and  a faceface with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. 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 Mg(1), one Fe(2), one Fe(3), and two equivalent Ni(1) atoms to form distorted OMgFe2Ni2 trigonal bipyramids that share corners with five equivalent O(4)Fe2Ni2 tetrahedra,  a cornercorner with one O(1)MgFe2Ni2 trigonal bipyramid, and  a faceface with one O(1)MgFe2Ni2 trigonal bipyramid. In the second O site, O(2) is bonded in a 5-coordinate geometry to one Fe(1), one Fe(2), two equivalent Fe(3), and one Ni(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), and two equivalent Fe(3) atoms. In the fourth O site, O(4) is bonded to one Fe(1), one Fe(3), and two equivalent Ni(1) atoms to form OFe2Ni2 tetrahedra that share  a cornercorner with one O(4)Fe2Ni2 tetrahedra, corners with five equivalent O(1)MgFe2Ni2 trigonal bipyramids, and  an edgeedge with one O(4)Fe2Ni2 tetrahedra. is represented by the CIF card [CIF]
data_MgFe4(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.153
_cell_length_b   6.392
_cell_length_c   6.153
_cell_angle_alpha   58.708
_cell_angle_beta   59.301
_cell_angle_gamma   58.708
_symmetry_Int_Tables_number   1
_cell_volume   166.854
_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  0.204  0.796  0.204  1.0
  Fe  Fe1  1  0.892  0.108  0.892  1.0
  Fe  Fe2  1  0.292  0.208  0.292  1.0
  Fe  Fe3  1  0.628  0.087  0.628  1.0
  Fe  Fe4  1  0.628  0.658  0.628  1.0
  Ni  Ni5  1  0.160  0.568  0.704  1.0
  Ni  Ni6  1  0.704  0.568  0.160  1.0
  O  O7  1  0.383  0.407  0.383  1.0
  O  O8  1  0.428  0.336  0.901  1.0
  O  O9  1  0.383  0.827  0.383  1.0
  O  O10  1  0.901  0.336  0.428  1.0
  O  O11  1  0.339  0.923  0.815  1.0
  O  O12  1  0.861  0.439  0.861  1.0
  O  O13  1  0.815  0.923  0.339  1.0
  O  O14  1  0.861  0.838  0.861  1.0
[/CIF]
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