The material described by MgCr2(SbO4)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(3), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form distorted MgO6 octahedra that share corners with two equivalent Sb(2)O6 octahedra, edges with four equivalent Cr(1)O6 octahedra, and  a faceface with one Sb(2)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. Cr(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CrO6 octahedra that share corners with four equivalent Sb(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-60°. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a 5-coordinate geometry to one O(3), one O(4), one O(5), and two equivalent O(2) atoms. In the second Sb site, Sb(2) is bonded to one O(4), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form SbO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with eight equivalent Cr(1)O6 octahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-60°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one Sb(2) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to one Mg(1), one Cr(1), one Sb(1), and one Sb(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Cr(1), and one Sb(1) atom. In the fourth O site, O(4) is bonded to two equivalent Cr(1), one Sb(1), and one Sb(2) atom to form a mixture of distorted corner and edge-sharing OCr2Sb2 trigonal pyramids. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Cr(1) and one Sb(1) atom. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent Cr(1), and one Sb(2) atom to form a mixture of corner and edge-sharing OMgCr2Sb trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCr2(SbO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.759
_cell_length_b   5.956
_cell_length_c   5.759
_cell_angle_alpha   71.507
_cell_angle_beta   69.586
_cell_angle_gamma   108.209
_symmetry_Int_Tables_number   1
_cell_volume   154.400
_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  0.796  0.031  0.765  1.0
  Cr  Cr1  1  0.739  0.516  0.763  1.0
  Cr  Cr2  1  0.278  0.516  0.224  1.0
  Sb  Sb3  1  0.062  0.955  0.106  1.0
  Sb  Sb4  1  0.501  0.049  0.451  1.0
  O  O5  1  0.741  0.202  0.034  1.0
  O  O6  1  0.237  0.202  0.539  1.0
  O  O7  1  0.737  0.854  0.505  1.0
  O  O8  1  0.358  0.854  0.883  1.0
  O  O9  1  0.689  0.661  0.028  1.0
  O  O10  1  0.195  0.753  0.442  1.0
  O  O11  1  0.327  0.334  0.993  1.0
  O  O12  1  0.812  0.342  0.469  1.0
[/CIF]
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The material described by MgCr2(SbO4)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(3), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form distorted MgO6 octahedra that share corners with two equivalent Sb(2)O6 octahedra, edges with four equivalent Cr(1)O6 octahedra, and  a faceface with one Sb(2)O6 octahedra. The corner-sharing octahedral tilt angles are 46°. Cr(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form CrO6 octahedra that share corners with four equivalent Sb(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-60°. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a 5-coordinate geometry to one O(3), one O(4), one O(5), and two equivalent O(2) atoms. In the second Sb site, Sb(2) is bonded to one O(4), one O(6), two equivalent O(1), and two equivalent O(2) atoms to form SbO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with eight equivalent Cr(1)O6 octahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 34-60°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Mg(1), one Cr(1), and one Sb(2) atom. In the second O site, O(2) is bonded in a distorted see-saw-like geometry to one Mg(1), one Cr(1), one Sb(1), and one Sb(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Cr(1), and one Sb(1) atom. In the fourth O site, O(4) is bonded to two equivalent Cr(1), one Sb(1), and one Sb(2) atom to form a mixture of distorted corner and edge-sharing OCr2Sb2 trigonal pyramids. In the fifth O site, O(5) is bonded in a trigonal planar geometry to two equivalent Cr(1) and one Sb(1) atom. In the sixth O site, O(6) is bonded to one Mg(1), two equivalent Cr(1), and one Sb(2) atom to form a mixture of corner and edge-sharing OMgCr2Sb trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCr2(SbO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.759
_cell_length_b   5.956
_cell_length_c   5.759
_cell_angle_alpha   71.507
_cell_angle_beta   69.586
_cell_angle_gamma   108.209
_symmetry_Int_Tables_number   1
_cell_volume   154.400
_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  0.796  0.031  0.765  1.0
  Cr  Cr1  1  0.739  0.516  0.763  1.0
  Cr  Cr2  1  0.278  0.516  0.224  1.0
  Sb  Sb3  1  0.062  0.955  0.106  1.0
  Sb  Sb4  1  0.501  0.049  0.451  1.0
  O  O5  1  0.741  0.202  0.034  1.0
  O  O6  1  0.237  0.202  0.539  1.0
  O  O7  1  0.737  0.854  0.505  1.0
  O  O8  1  0.358  0.854  0.883  1.0
  O  O9  1  0.689  0.661  0.028  1.0
  O  O10  1  0.195  0.753  0.442  1.0
  O  O11  1  0.327  0.334  0.993  1.0
  O  O12  1  0.812  0.342  0.469  1.0
[/CIF]
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