The material structure described by MgCr6O16 crystallizes in the monoclinic P2 space group. Mg(1) is bonded to two equivalent O(4), two equivalent O(6), and two equivalent O(7) atoms to form MgO6 octahedra that share corners with two equivalent Cr(3)O4 tetrahedra, corners with four equivalent Cr(2)O4 tetrahedra, and edges with two equivalent Cr(4)O6 octahedra. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(8) atoms to form corner-sharing CrO6 octahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form CrO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, and corners with two equivalent Cr(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-55°. In the third Cr site, Cr(3) is bonded to one O(3), one O(5), one O(6), and one O(8) atom to form CrO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(4)O6 octahedra, and corners with two equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-47°. In the fourth Cr site, Cr(4) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(7) atoms to form CrO6 octahedra that share corners with two equivalent Cr(3)O4 tetrahedra, corners with four equivalent Cr(2)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one Cr(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one Cr(3) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(2), and one Cr(4) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Cr(3) and one Cr(4) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one Cr(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(2), and one Cr(4) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one Cr(3) atom. is represented by the CIF card [CIF]
data_MgCr6O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.554
_cell_length_b   8.506
_cell_length_c   6.442
_cell_angle_alpha   91.691
_cell_angle_beta   90.019
_cell_angle_gamma   89.994
_symmetry_Int_Tables_number   1
_cell_volume   304.203
_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  0.521  0.500  0.000  1.0
  Cr  Cr1  1  0.015  0.000  0.000  1.0
  Cr  Cr2  1  0.019  0.650  0.270  1.0
  Cr  Cr3  1  0.019  0.350  0.730  1.0
  Cr  Cr4  1  0.515  0.152  0.226  1.0
  Cr  Cr5  1  0.515  0.848  0.774  1.0
  Cr  Cr6  1  0.519  0.500  0.500  1.0
  O  O7  1  0.018  0.250  0.520  1.0
  O  O8  1  0.017  0.768  0.069  1.0
  O  O9  1  0.017  0.232  0.931  1.0
  O  O10  1  0.018  0.750  0.480  1.0
  O  O11  1  0.268  0.040  0.215  1.0
  O  O12  1  0.267  0.960  0.785  1.0
  O  O13  1  0.277  0.466  0.736  1.0
  O  O14  1  0.277  0.534  0.264  1.0
  O  O15  1  0.517  0.269  0.441  1.0
  O  O16  1  0.516  0.265  0.026  1.0
  O  O17  1  0.517  0.731  0.559  1.0
  O  O18  1  0.516  0.735  0.974  1.0
  O  O19  1  0.761  0.468  0.736  1.0
  O  O20  1  0.761  0.532  0.264  1.0
  O  O21  1  0.762  0.039  0.215  1.0
  O  O22  1  0.761  0.962  0.786  1.0
[/CIF]
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The material structure described by MgCr6O16 crystallizes in the monoclinic P2 space group. Mg(1) is bonded to two equivalent O(4), two equivalent O(6), and two equivalent O(7) atoms to form MgO6 octahedra that share corners with two equivalent Cr(3)O4 tetrahedra, corners with four equivalent Cr(2)O4 tetrahedra, and edges with two equivalent Cr(4)O6 octahedra. There are four inequivalent Cr sites. In the first Cr site, Cr(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(8) atoms to form corner-sharing CrO6 octahedra. In the second Cr site, Cr(2) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form CrO4 tetrahedra that share  a cornercorner with one Cr(1)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, and corners with two equivalent Cr(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-55°. In the third Cr site, Cr(3) is bonded to one O(3), one O(5), one O(6), and one O(8) atom to form CrO4 tetrahedra that share  a cornercorner with one Mg(1)O6 octahedra,  a cornercorner with one Cr(4)O6 octahedra, and corners with two equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-47°. In the fourth Cr site, Cr(4) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(7) atoms to form CrO6 octahedra that share corners with two equivalent Cr(3)O4 tetrahedra, corners with four equivalent Cr(2)O4 tetrahedra, and edges with two equivalent Mg(1)O6 octahedra. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a single-bond geometry to one Cr(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Cr(1) and one Cr(2) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one Cr(3) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(2), and one Cr(4) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Cr(3) and one Cr(4) atom. In the sixth O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one Cr(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(2), and one Cr(4) atom. In the eighth O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Cr(1) and one Cr(3) atom. is represented by the CIF card [CIF]
data_MgCr6O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.554
_cell_length_b   8.506
_cell_length_c   6.442
_cell_angle_alpha   91.691
_cell_angle_beta   90.019
_cell_angle_gamma   89.994
_symmetry_Int_Tables_number   1
_cell_volume   304.203
_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  0.521  0.500  0.000  1.0
  Cr  Cr1  1  0.015  0.000  0.000  1.0
  Cr  Cr2  1  0.019  0.650  0.270  1.0
  Cr  Cr3  1  0.019  0.350  0.730  1.0
  Cr  Cr4  1  0.515  0.152  0.226  1.0
  Cr  Cr5  1  0.515  0.848  0.774  1.0
  Cr  Cr6  1  0.519  0.500  0.500  1.0
  O  O7  1  0.018  0.250  0.520  1.0
  O  O8  1  0.017  0.768  0.069  1.0
  O  O9  1  0.017  0.232  0.931  1.0
  O  O10  1  0.018  0.750  0.480  1.0
  O  O11  1  0.268  0.040  0.215  1.0
  O  O12  1  0.267  0.960  0.785  1.0
  O  O13  1  0.277  0.466  0.736  1.0
  O  O14  1  0.277  0.534  0.264  1.0
  O  O15  1  0.517  0.269  0.441  1.0
  O  O16  1  0.516  0.265  0.026  1.0
  O  O17  1  0.517  0.731  0.559  1.0
  O  O18  1  0.516  0.735  0.974  1.0
  O  O19  1  0.761  0.468  0.736  1.0
  O  O20  1  0.761  0.532  0.264  1.0
  O  O21  1  0.762  0.039  0.215  1.0
  O  O22  1  0.761  0.962  0.786  1.0
[/CIF]
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