The material structure described by MgCr2(NiO4)2 crystallizes in the orthorhombic Amm2 space group. Mg(1) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(4) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to two equivalent O(2) and two equivalent O(4) atoms. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(3) atoms. Ni(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Cr(2) and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded to one Mg(1), one Cr(1), and two equivalent Ni(1) atoms to form a mixture of distorted face and corner-sharing OMgCrNi2 tetrahedra. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cr(2) and one Ni(1) atom. In the fourth O site, O(4) is bonded in an L-shaped geometry to one Mg(1) and one Cr(1) atom. is represented by the CIF card [CIF]
data_MgCr2(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.582
_cell_length_b   5.582
_cell_length_c   6.236
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.421
_symmetry_Int_Tables_number   1
_cell_volume   169.232
_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  0.844  0.156  0.250  1.0
  Cr  Cr1  1  0.580  0.420  0.250  1.0
  Cr  Cr2  1  0.388  0.612  0.750  1.0
  Ni  Ni3  1  0.068  0.931  0.528  1.0
  Ni  Ni4  1  0.068  0.931  0.972  1.0
  O  O5  1  0.232  0.244  0.750  1.0
  O  O6  1  0.791  0.782  0.250  1.0
  O  O7  1  0.218  0.209  0.250  1.0
  O  O8  1  0.756  0.768  0.750  1.0
  O  O9  1  0.276  0.724  0.963  1.0
  O  O10  1  0.690  0.310  0.459  1.0
  O  O11  1  0.690  0.310  0.041  1.0
  O  O12  1  0.276  0.724  0.537  1.0
[/CIF]
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The material structure described by MgCr2(NiO4)2 crystallizes in the orthorhombic Amm2 space group. Mg(1) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(4) atoms. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a tetrahedral geometry to two equivalent O(2) and two equivalent O(4) atoms. In the second Cr site, Cr(2) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(3) atoms. Ni(1) is bonded in a 5-coordinate geometry to one O(3), two equivalent O(1), and two equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Cr(2) and two equivalent Ni(1) atoms. In the second O site, O(2) is bonded to one Mg(1), one Cr(1), and two equivalent Ni(1) atoms to form a mixture of distorted face and corner-sharing OMgCrNi2 tetrahedra. In the third O site, O(3) is bonded in a bent 120 degrees geometry to one Cr(2) and one Ni(1) atom. In the fourth O site, O(4) is bonded in an L-shaped geometry to one Mg(1) and one Cr(1) atom. is represented by the CIF card [CIF]
data_MgCr2(NiO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.582
_cell_length_b   5.582
_cell_length_c   6.236
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.421
_symmetry_Int_Tables_number   1
_cell_volume   169.232
_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  0.844  0.156  0.250  1.0
  Cr  Cr1  1  0.580  0.420  0.250  1.0
  Cr  Cr2  1  0.388  0.612  0.750  1.0
  Ni  Ni3  1  0.068  0.931  0.528  1.0
  Ni  Ni4  1  0.068  0.931  0.972  1.0
  O  O5  1  0.232  0.244  0.750  1.0
  O  O6  1  0.791  0.782  0.250  1.0
  O  O7  1  0.218  0.209  0.250  1.0
  O  O8  1  0.756  0.768  0.750  1.0
  O  O9  1  0.276  0.724  0.963  1.0
  O  O10  1  0.690  0.310  0.459  1.0
  O  O11  1  0.690  0.310  0.041  1.0
  O  O12  1  0.276  0.724  0.537  1.0
[/CIF]
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