The compound described by MgTh3 is Copper-derived structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Th(1) and eight equivalent Th(2) atoms to form MgTh12 cuboctahedra that share corners with four equivalent Mg(1)Th12 cuboctahedra, corners with eight equivalent Th(1)Th8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Th12 cuboctahedra, edges with sixteen equivalent Th(2)Th8Mg4 cuboctahedra, faces with four equivalent Mg(1)Th12 cuboctahedra, faces with six equivalent Th(1)Th8Mg4 cuboctahedra, and faces with eight equivalent Th(2)Th8Mg4 cuboctahedra. There are two inequivalent Th sites. In the first Th site, Th(1) is bonded to four equivalent Mg(1) and eight equivalent Th(2) atoms to form ThTh8Mg4 cuboctahedra that share corners with four equivalent Th(1)Th8Mg4 cuboctahedra, corners with eight equivalent Mg(1)Th12 cuboctahedra, edges with eight equivalent Th(1)Th8Mg4 cuboctahedra, edges with sixteen equivalent Th(2)Th8Mg4 cuboctahedra, faces with four equivalent Th(1)Th8Mg4 cuboctahedra, faces with six equivalent Mg(1)Th12 cuboctahedra, and faces with eight equivalent Th(2)Th8Mg4 cuboctahedra. In the second Th site, Th(2) is bonded to four equivalent Mg(1), four equivalent Th(1), and four equivalent Th(2) atoms to form ThTh8Mg4 cuboctahedra that share corners with twelve equivalent Th(2)Th8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Th12 cuboctahedra, edges with eight equivalent Th(1)Th8Mg4 cuboctahedra, edges with eight equivalent Th(2)Th8Mg4 cuboctahedra, faces with four equivalent Mg(1)Th12 cuboctahedra, faces with four equivalent Th(1)Th8Mg4 cuboctahedra, and faces with ten equivalent Th(2)Th8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_Th3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.129
_cell_length_b   6.129
_cell_length_c   6.129
_cell_angle_alpha   132.593
_cell_angle_beta   132.593
_cell_angle_gamma   69.294
_symmetry_Int_Tables_number   1
_cell_volume   122.432
_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
  Th  Th0  1  0.500  0.500  0.000  1.0
  Th  Th1  1  0.750  0.250  0.500  1.0
  Th  Th2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
[/CIF]
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The compound described by MgTh3 is Copper-derived structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Th(1) and eight equivalent Th(2) atoms to form MgTh12 cuboctahedra that share corners with four equivalent Mg(1)Th12 cuboctahedra, corners with eight equivalent Th(1)Th8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Th12 cuboctahedra, edges with sixteen equivalent Th(2)Th8Mg4 cuboctahedra, faces with four equivalent Mg(1)Th12 cuboctahedra, faces with six equivalent Th(1)Th8Mg4 cuboctahedra, and faces with eight equivalent Th(2)Th8Mg4 cuboctahedra. There are two inequivalent Th sites. In the first Th site, Th(1) is bonded to four equivalent Mg(1) and eight equivalent Th(2) atoms to form ThTh8Mg4 cuboctahedra that share corners with four equivalent Th(1)Th8Mg4 cuboctahedra, corners with eight equivalent Mg(1)Th12 cuboctahedra, edges with eight equivalent Th(1)Th8Mg4 cuboctahedra, edges with sixteen equivalent Th(2)Th8Mg4 cuboctahedra, faces with four equivalent Th(1)Th8Mg4 cuboctahedra, faces with six equivalent Mg(1)Th12 cuboctahedra, and faces with eight equivalent Th(2)Th8Mg4 cuboctahedra. In the second Th site, Th(2) is bonded to four equivalent Mg(1), four equivalent Th(1), and four equivalent Th(2) atoms to form ThTh8Mg4 cuboctahedra that share corners with twelve equivalent Th(2)Th8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Th12 cuboctahedra, edges with eight equivalent Th(1)Th8Mg4 cuboctahedra, edges with eight equivalent Th(2)Th8Mg4 cuboctahedra, faces with four equivalent Mg(1)Th12 cuboctahedra, faces with four equivalent Th(1)Th8Mg4 cuboctahedra, and faces with ten equivalent Th(2)Th8Mg4 cuboctahedra. is represented by the CIF file [CIF]
data_Th3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.129
_cell_length_b   6.129
_cell_length_c   6.129
_cell_angle_alpha   132.593
_cell_angle_beta   132.593
_cell_angle_gamma   69.294
_symmetry_Int_Tables_number   1
_cell_volume   122.432
_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
  Th  Th0  1  0.500  0.500  0.000  1.0
  Th  Th1  1  0.750  0.250  0.500  1.0
  Th  Th2  1  0.250  0.750  0.500  1.0
  Mg  Mg3  1  0.000  0.000  0.000  1.0
[/CIF]
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