The crystal structure described by MgHo6WO12 crystallizes in the trigonal R3 space group. Mg(1) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form MgO6 octahedra that share  a faceface with one W(1)O6 octahedra. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 7-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. In the second Ho site, Ho(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. W(1) is bonded to three equivalent O(3) and three equivalent O(4) atoms to form WO6 octahedra that share  a faceface with one Mg(1)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Ho(1), and two equivalent Ho(2) atoms to form distorted OHo4Mg square pyramids that share corners with two equivalent O(1)Ho4Mg square pyramids, corners with two equivalent O(2)Ho4 tetrahedra, corners with two equivalent O(3)Ho3W trigonal pyramids, edges with two equivalent O(1)Ho4Mg square pyramids, edges with three equivalent O(2)Ho4 tetrahedra, and edges with two equivalent O(3)Ho3W trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Ho(1) and two equivalent Ho(2) atoms to form OHo4 tetrahedra that share corners with two equivalent O(1)Ho4Mg square pyramids, corners with four equivalent O(2)Ho4 tetrahedra, corners with six equivalent O(3)Ho3W trigonal pyramids, and edges with three equivalent O(1)Ho4Mg square pyramids. In the third O site, O(3) is bonded to one Ho(1), two equivalent Ho(2), and one W(1) atom to form distorted OHo3W trigonal pyramids that share corners with two equivalent O(1)Ho4Mg square pyramids, corners with six equivalent O(2)Ho4 tetrahedra, corners with four equivalent O(3)Ho3W trigonal pyramids, and edges with two equivalent O(1)Ho4Mg square pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Ho(1), and one W(1) atom. is represented by the CIF file [CIF]
data_Ho6MgWO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.533
_cell_length_b   6.533
_cell_length_c   6.533
_cell_angle_alpha   99.552
_cell_angle_beta   99.552
_cell_angle_gamma   99.552
_symmetry_Int_Tables_number   1
_cell_volume   265.704
_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
  Ho  Ho0  1  0.132  0.302  0.651  1.0
  Ho  Ho1  1  0.670  0.395  0.858  1.0
  Ho  Ho2  1  0.395  0.858  0.670  1.0
  Ho  Ho3  1  0.651  0.132  0.302  1.0
  Ho  Ho4  1  0.302  0.651  0.132  1.0
  Ho  Ho5  1  0.858  0.670  0.395  1.0
  Mg  Mg6  1  0.272  0.272  0.272  1.0
  W  W7  1  0.982  0.982  0.982  1.0
  O  O8  1  0.418  0.190  0.558  1.0
  O  O9  1  0.190  0.558  0.418  1.0
  O  O10  1  0.558  0.418  0.190  1.0
  O  O11  1  0.581  0.828  0.408  1.0
  O  O12  1  0.828  0.408  0.581  1.0
  O  O13  1  0.408  0.581  0.828  1.0
  O  O14  1  0.055  0.918  0.682  1.0
  O  O15  1  0.306  0.981  0.093  1.0
  O  O16  1  0.093  0.306  0.981  1.0
  O  O17  1  0.918  0.682  0.055  1.0
  O  O18  1  0.682  0.055  0.918  1.0
  O  O19  1  0.981  0.093  0.306  1.0
[/CIF]
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The crystal structure described by MgHo6WO12 crystallizes in the trigonal R3 space group. Mg(1) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form MgO6 octahedra that share  a faceface with one W(1)O6 octahedra. There are two inequivalent Ho sites. In the first Ho site, Ho(1) is bonded in a 7-coordinate geometry to one O(3), two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms. In the second Ho site, Ho(2) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. W(1) is bonded to three equivalent O(3) and three equivalent O(4) atoms to form WO6 octahedra that share  a faceface with one Mg(1)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), two equivalent Ho(1), and two equivalent Ho(2) atoms to form distorted OHo4Mg square pyramids that share corners with two equivalent O(1)Ho4Mg square pyramids, corners with two equivalent O(2)Ho4 tetrahedra, corners with two equivalent O(3)Ho3W trigonal pyramids, edges with two equivalent O(1)Ho4Mg square pyramids, edges with three equivalent O(2)Ho4 tetrahedra, and edges with two equivalent O(3)Ho3W trigonal pyramids. In the second O site, O(2) is bonded to two equivalent Ho(1) and two equivalent Ho(2) atoms to form OHo4 tetrahedra that share corners with two equivalent O(1)Ho4Mg square pyramids, corners with four equivalent O(2)Ho4 tetrahedra, corners with six equivalent O(3)Ho3W trigonal pyramids, and edges with three equivalent O(1)Ho4Mg square pyramids. In the third O site, O(3) is bonded to one Ho(1), two equivalent Ho(2), and one W(1) atom to form distorted OHo3W trigonal pyramids that share corners with two equivalent O(1)Ho4Mg square pyramids, corners with six equivalent O(2)Ho4 tetrahedra, corners with four equivalent O(3)Ho3W trigonal pyramids, and edges with two equivalent O(1)Ho4Mg square pyramids. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), two equivalent Ho(1), and one W(1) atom. is represented by the CIF file [CIF]
data_Ho6MgWO12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.533
_cell_length_b   6.533
_cell_length_c   6.533
_cell_angle_alpha   99.552
_cell_angle_beta   99.552
_cell_angle_gamma   99.552
_symmetry_Int_Tables_number   1
_cell_volume   265.704
_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
  Ho  Ho0  1  0.132  0.302  0.651  1.0
  Ho  Ho1  1  0.670  0.395  0.858  1.0
  Ho  Ho2  1  0.395  0.858  0.670  1.0
  Ho  Ho3  1  0.651  0.132  0.302  1.0
  Ho  Ho4  1  0.302  0.651  0.132  1.0
  Ho  Ho5  1  0.858  0.670  0.395  1.0
  Mg  Mg6  1  0.272  0.272  0.272  1.0
  W  W7  1  0.982  0.982  0.982  1.0
  O  O8  1  0.418  0.190  0.558  1.0
  O  O9  1  0.190  0.558  0.418  1.0
  O  O10  1  0.558  0.418  0.190  1.0
  O  O11  1  0.581  0.828  0.408  1.0
  O  O12  1  0.828  0.408  0.581  1.0
  O  O13  1  0.408  0.581  0.828  1.0
  O  O14  1  0.055  0.918  0.682  1.0
  O  O15  1  0.306  0.981  0.093  1.0
  O  O16  1  0.093  0.306  0.981  1.0
  O  O17  1  0.918  0.682  0.055  1.0
  O  O18  1  0.682  0.055  0.918  1.0
  O  O19  1  0.981  0.093  0.306  1.0
[/CIF]
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