The material structure described by MgCr2O4 crystallizes in the orthorhombic Amm2 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 four equivalent Cr(2)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, and  an edgeedge with one Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-60°. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(3) atoms. In the second Cr site, Cr(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CrO6 octahedra that share corners with four equivalent Mg(1)O4 tetrahedra, edges with two equivalent Cr(2)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Cr(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Cr(1) and two equivalent Cr(2) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(2), and two equivalent Cr(1) atoms. is represented by the CIF card [CIF]
data_MgCr2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.012
_cell_length_b   5.235
_cell_length_c   5.235
_cell_angle_alpha   104.142
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   80.038
_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  0.000  0.296  0.704  1.0
  Cr  Cr1  1  0.500  0.582  0.418  1.0
  Cr  Cr2  1  0.000  0.972  0.028  1.0
  O  O3  1  0.500  0.148  0.852  1.0
  O  O4  1  0.500  0.813  0.187  1.0
  O  O5  1  0.000  0.311  0.316  1.0
  O  O6  1  0.000  0.684  0.689  1.0
[/CIF]
.
The material structure described by MgCr2O4 crystallizes in the orthorhombic Amm2 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 four equivalent Cr(2)O6 octahedra, corners with two equivalent Mg(1)O4 tetrahedra, and  an edgeedge with one Cr(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 5-60°. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a 5-coordinate geometry to one O(2) and four equivalent O(3) atoms. In the second Cr site, Cr(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form CrO6 octahedra that share corners with four equivalent Mg(1)O4 tetrahedra, edges with two equivalent Cr(2)O6 octahedra, and  an edgeedge with one Mg(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to two equivalent Mg(1) and two equivalent Cr(2) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Cr(1) and two equivalent Cr(2) atoms. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Cr(2), and two equivalent Cr(1) atoms. is represented by the CIF card [CIF]
data_MgCr2O4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.012
_cell_length_b   5.235
_cell_length_c   5.235
_cell_angle_alpha   104.142
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   80.038
_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  0.000  0.296  0.704  1.0
  Cr  Cr1  1  0.500  0.582  0.418  1.0
  Cr  Cr2  1  0.000  0.972  0.028  1.0
  O  O3  1  0.500  0.148  0.852  1.0
  O  O4  1  0.500  0.813  0.187  1.0
  O  O5  1  0.000  0.311  0.316  1.0
  O  O6  1  0.000  0.684  0.689  1.0
[/CIF]
.