The compound described by MgCr2O6 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(6) atom to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Cr(2)O4 tetrahedra, corners with three equivalent Cr(1)O4 tetrahedra, and  an edgeedge with one Cr(2)O4 tetrahedra. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form CrO4 tetrahedra that share corners with two equivalent Cr(2)O4 tetrahedra and corners with three equivalent Mg(1)O5 trigonal bipyramids. In the second Cr site, Cr(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form CrO4 tetrahedra that share corners with two equivalent Cr(1)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Mg(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Mg(1) and one Cr(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one Cr(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fifth O site, O(5) is bonded in an L-shaped geometry to one Mg(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Mg(1) and one Cr(1) atom. is represented by the CIF card [CIF]
data_MgCr2O6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.541
_cell_length_b   5.905
_cell_length_c   5.508
_cell_angle_alpha   87.681
_cell_angle_beta   87.038
_cell_angle_gamma   118.651
_symmetry_Int_Tables_number   1
_cell_volume   157.516
_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  0.313  0.224  0.011  1.0
  Cr  Cr1  1  0.632  0.832  0.255  1.0
  Cr  Cr2  1  0.740  0.172  0.745  1.0
  O  O3  1  0.968  0.939  0.201  1.0
  O  O4  1  0.068  0.258  0.770  1.0
  O  O5  1  0.555  0.037  0.051  1.0
  O  O6  1  0.567  0.910  0.554  1.0
  O  O7  1  0.636  0.390  0.716  1.0
  O  O8  1  0.420  0.526  0.207  1.0
[/CIF]
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The compound described by MgCr2O6 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(3), one O(5), and one O(6) atom to form distorted MgO5 trigonal bipyramids that share  a cornercorner with one Cr(2)O4 tetrahedra, corners with three equivalent Cr(1)O4 tetrahedra, and  an edgeedge with one Cr(2)O4 tetrahedra. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to one O(1), one O(3), one O(4), and one O(6) atom to form CrO4 tetrahedra that share corners with two equivalent Cr(2)O4 tetrahedra and corners with three equivalent Mg(1)O5 trigonal bipyramids. In the second Cr site, Cr(2) is bonded to one O(2), one O(3), one O(4), and one O(5) atom to form CrO4 tetrahedra that share corners with two equivalent Cr(1)O4 tetrahedra,  a cornercorner with one Mg(1)O5 trigonal bipyramid, and  an edgeedge with one Mg(1)O5 trigonal bipyramid. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Mg(1) and one Cr(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Mg(1) and one Cr(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one Cr(2) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the fifth O site, O(5) is bonded in an L-shaped geometry to one Mg(1) and one Cr(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Mg(1) and one Cr(1) atom. is represented by the CIF card [CIF]
data_MgCr2O6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.541
_cell_length_b   5.905
_cell_length_c   5.508
_cell_angle_alpha   87.681
_cell_angle_beta   87.038
_cell_angle_gamma   118.651
_symmetry_Int_Tables_number   1
_cell_volume   157.516
_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  0.313  0.224  0.011  1.0
  Cr  Cr1  1  0.632  0.832  0.255  1.0
  Cr  Cr2  1  0.740  0.172  0.745  1.0
  O  O3  1  0.968  0.939  0.201  1.0
  O  O4  1  0.068  0.258  0.770  1.0
  O  O5  1  0.555  0.037  0.051  1.0
  O  O6  1  0.567  0.910  0.554  1.0
  O  O7  1  0.636  0.390  0.716  1.0
  O  O8  1  0.420  0.526  0.207  1.0
[/CIF]
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