The compound described by Mg(ReO4)2 crystallizes in the trigonal P31m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form MgO6 octahedra that share corners with three equivalent Re(1)O4 tetrahedra and corners with three equivalent Re(2)O4 tetrahedra. In the second Mg site, Mg(2) is bonded to three equivalent O(1) and three equivalent O(6) atoms to form MgO6 octahedra that share corners with three equivalent Re(1)O4 tetrahedra and corners with three equivalent Re(2)O4 tetrahedra. There are two inequivalent Re sites. In the first Re site, Re(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form ReO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra and corners with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-46°. In the second Re site, Re(2) is bonded to one O(4), one O(6), and two equivalent O(5) atoms to form ReO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra and corners with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-41°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Mg(2) and one Re(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Re(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one Re(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Re(2) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Mg(1) and one Re(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Mg(2) and one Re(2) atom. is represented by the CIF card [CIF]
data_Mg(ReO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.436
_cell_length_b   10.436
_cell_length_c   5.127
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   483.636
_cell_formula_units_Z   3
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  0.333  0.667  0.362  1.0
  Mg  Mg1  1  0.000  0.000  0.863  1.0
  Mg  Mg2  1  0.667  0.333  0.362  1.0
  Re  Re3  1  0.000  0.683  0.488  1.0
  Re  Re4  1  0.000  0.355  0.006  1.0
  Re  Re5  1  0.317  0.317  0.488  1.0
  Re  Re6  1  0.645  0.645  0.006  1.0
  Re  Re7  1  0.355  0.000  0.006  1.0
  Re  Re8  1  0.683  0.000  0.488  1.0
  O  O9  1  0.000  0.837  0.628  1.0
  O  O10  1  0.000  0.694  0.152  1.0
  O  O11  1  0.162  0.680  0.577  1.0
  O  O12  1  0.000  0.370  0.672  1.0
  O  O13  1  0.159  0.511  0.132  1.0
  O  O14  1  0.000  0.190  0.077  1.0
  O  O15  1  0.352  0.841  0.132  1.0
  O  O16  1  0.320  0.482  0.577  1.0
  O  O17  1  0.163  0.163  0.628  1.0
  O  O18  1  0.306  0.306  0.152  1.0
  O  O19  1  0.518  0.838  0.577  1.0
  O  O20  1  0.489  0.648  0.132  1.0
  O  O21  1  0.190  0.000  0.077  1.0
  O  O22  1  0.482  0.320  0.577  1.0
  O  O23  1  0.630  0.630  0.672  1.0
  O  O24  1  0.648  0.489  0.132  1.0
  O  O25  1  0.810  0.810  0.077  1.0
  O  O26  1  0.370  0.000  0.672  1.0
  O  O27  1  0.511  0.159  0.132  1.0
  O  O28  1  0.838  0.518  0.577  1.0
  O  O29  1  0.680  0.162  0.577  1.0
  O  O30  1  0.841  0.352  0.132  1.0
  O  O31  1  0.694  0.000  0.152  1.0
  O  O32  1  0.837  0.000  0.628  1.0
[/CIF]
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The compound described by Mg(ReO4)2 crystallizes in the trigonal P31m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form MgO6 octahedra that share corners with three equivalent Re(1)O4 tetrahedra and corners with three equivalent Re(2)O4 tetrahedra. In the second Mg site, Mg(2) is bonded to three equivalent O(1) and three equivalent O(6) atoms to form MgO6 octahedra that share corners with three equivalent Re(1)O4 tetrahedra and corners with three equivalent Re(2)O4 tetrahedra. There are two inequivalent Re sites. In the first Re site, Re(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form ReO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra and corners with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-46°. In the second Re site, Re(2) is bonded to one O(4), one O(6), and two equivalent O(5) atoms to form ReO4 tetrahedra that share  a cornercorner with one Mg(2)O6 octahedra and corners with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 13-41°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to one Mg(2) and one Re(1) atom. In the second O site, O(2) is bonded in a single-bond geometry to one Re(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Mg(1) and one Re(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Re(2) atom. In the fifth O site, O(5) is bonded in a linear geometry to one Mg(1) and one Re(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Mg(2) and one Re(2) atom. is represented by the CIF card [CIF]
data_Mg(ReO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.436
_cell_length_b   10.436
_cell_length_c   5.127
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   483.636
_cell_formula_units_Z   3
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  0.333  0.667  0.362  1.0
  Mg  Mg1  1  0.000  0.000  0.863  1.0
  Mg  Mg2  1  0.667  0.333  0.362  1.0
  Re  Re3  1  0.000  0.683  0.488  1.0
  Re  Re4  1  0.000  0.355  0.006  1.0
  Re  Re5  1  0.317  0.317  0.488  1.0
  Re  Re6  1  0.645  0.645  0.006  1.0
  Re  Re7  1  0.355  0.000  0.006  1.0
  Re  Re8  1  0.683  0.000  0.488  1.0
  O  O9  1  0.000  0.837  0.628  1.0
  O  O10  1  0.000  0.694  0.152  1.0
  O  O11  1  0.162  0.680  0.577  1.0
  O  O12  1  0.000  0.370  0.672  1.0
  O  O13  1  0.159  0.511  0.132  1.0
  O  O14  1  0.000  0.190  0.077  1.0
  O  O15  1  0.352  0.841  0.132  1.0
  O  O16  1  0.320  0.482  0.577  1.0
  O  O17  1  0.163  0.163  0.628  1.0
  O  O18  1  0.306  0.306  0.152  1.0
  O  O19  1  0.518  0.838  0.577  1.0
  O  O20  1  0.489  0.648  0.132  1.0
  O  O21  1  0.190  0.000  0.077  1.0
  O  O22  1  0.482  0.320  0.577  1.0
  O  O23  1  0.630  0.630  0.672  1.0
  O  O24  1  0.648  0.489  0.132  1.0
  O  O25  1  0.810  0.810  0.077  1.0
  O  O26  1  0.370  0.000  0.672  1.0
  O  O27  1  0.511  0.159  0.132  1.0
  O  O28  1  0.838  0.518  0.577  1.0
  O  O29  1  0.680  0.162  0.577  1.0
  O  O30  1  0.841  0.352  0.132  1.0
  O  O31  1  0.694  0.000  0.152  1.0
  O  O32  1  0.837  0.000  0.628  1.0
[/CIF]
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