The crystal structure described by Mg2TaCrO6 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(3) atoms. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), two equivalent O(3), and four equivalent O(4) atoms. Ta(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra and corners with four equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-43°. Cr(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form CrO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra and corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-44°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Mg(2), and two equivalent Ta(1) atoms to form distorted OMg2Ta2 trigonal pyramids that share corners with two equivalent O(2)Mg2Cr2 trigonal pyramids and corners with two equivalent O(1)Mg2Ta2 trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1), one Mg(2), and two equivalent Cr(1) atoms to form distorted OMg2Cr2 trigonal pyramids that share corners with two equivalent O(2)Mg2Cr2 trigonal pyramids and corners with two equivalent O(1)Mg2Ta2 trigonal pyramids. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(2), one Ta(1), and one Cr(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Mg(2), one Ta(1), and one Cr(1) atom. is represented by the CIF file [CIF]
data_Mg2TaCrO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.187
_cell_length_b   5.376
_cell_length_c   7.594
_cell_angle_alpha   89.999
_cell_angle_beta   90.000
_cell_angle_gamma   89.616
_symmetry_Int_Tables_number   1
_cell_volume   211.761
_cell_formula_units_Z   2
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
  Cr  Cr0  1  0.500  -0.000  0.000  1.0
  Cr  Cr1  1  0.500  1.000  0.500  1.0
  Mg  Mg2  1  0.999  0.962  0.250  1.0
  Mg  Mg3  1  0.001  0.038  0.750  1.0
  Mg  Mg4  1  0.490  0.436  0.250  1.0
  Mg  Mg5  1  0.510  0.564  0.750  1.0
  O  O6  1  0.130  0.438  0.750  1.0
  O  O7  1  0.870  0.562  0.250  1.0
  O  O8  1  0.626  0.071  0.250  1.0
  O  O9  1  0.374  0.929  0.750  1.0
  O  O10  1  0.825  0.813  0.567  1.0
  O  O11  1  0.175  0.187  0.433  1.0
  O  O12  1  0.825  0.813  0.933  1.0
  O  O13  1  0.175  0.187  0.067  1.0
  O  O14  1  0.317  0.680  0.433  1.0
  O  O15  1  0.683  0.320  0.933  1.0
  O  O16  1  0.683  0.320  0.567  1.0
  O  O17  1  0.317  0.680  0.067  1.0
  Ta  Ta18  1  1.000  0.500  -0.000  1.0
  Ta  Ta19  1  1.000  0.500  0.500  1.0
[/CIF]
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The crystal structure described by Mg2TaCrO6 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), and two equivalent O(3) atoms. In the second Mg site, Mg(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), two equivalent O(3), and four equivalent O(4) atoms. Ta(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra and corners with four equivalent Cr(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-43°. Cr(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form CrO6 octahedra that share corners with two equivalent Cr(1)O6 octahedra and corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-44°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Mg(2), and two equivalent Ta(1) atoms to form distorted OMg2Ta2 trigonal pyramids that share corners with two equivalent O(2)Mg2Cr2 trigonal pyramids and corners with two equivalent O(1)Mg2Ta2 trigonal pyramids. In the second O site, O(2) is bonded to one Mg(1), one Mg(2), and two equivalent Cr(1) atoms to form distorted OMg2Cr2 trigonal pyramids that share corners with two equivalent O(2)Mg2Cr2 trigonal pyramids and corners with two equivalent O(1)Mg2Ta2 trigonal pyramids. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Mg(1), one Mg(2), one Ta(1), and one Cr(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Mg(2), one Ta(1), and one Cr(1) atom. is represented by the CIF file [CIF]
data_Mg2TaCrO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.187
_cell_length_b   5.376
_cell_length_c   7.594
_cell_angle_alpha   89.999
_cell_angle_beta   90.000
_cell_angle_gamma   89.616
_symmetry_Int_Tables_number   1
_cell_volume   211.761
_cell_formula_units_Z   2
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
  Cr  Cr0  1  0.500  -0.000  0.000  1.0
  Cr  Cr1  1  0.500  1.000  0.500  1.0
  Mg  Mg2  1  0.999  0.962  0.250  1.0
  Mg  Mg3  1  0.001  0.038  0.750  1.0
  Mg  Mg4  1  0.490  0.436  0.250  1.0
  Mg  Mg5  1  0.510  0.564  0.750  1.0
  O  O6  1  0.130  0.438  0.750  1.0
  O  O7  1  0.870  0.562  0.250  1.0
  O  O8  1  0.626  0.071  0.250  1.0
  O  O9  1  0.374  0.929  0.750  1.0
  O  O10  1  0.825  0.813  0.567  1.0
  O  O11  1  0.175  0.187  0.433  1.0
  O  O12  1  0.825  0.813  0.933  1.0
  O  O13  1  0.175  0.187  0.067  1.0
  O  O14  1  0.317  0.680  0.433  1.0
  O  O15  1  0.683  0.320  0.933  1.0
  O  O16  1  0.683  0.320  0.567  1.0
  O  O17  1  0.317  0.680  0.067  1.0
  Ta  Ta18  1  1.000  0.500  -0.000  1.0
  Ta  Ta19  1  1.000  0.500  0.500  1.0
[/CIF]
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