The compound described by SmMg2Bi2 crystallizes in the trigonal P-3m1 space group. Mg(1) is bonded to four equivalent Bi(1) atoms to form MgBi4 tetrahedra that share corners with six equivalent Sm(1)Bi6 octahedra, corners with six equivalent Mg(1)Bi4 tetrahedra, edges with three equivalent Sm(1)Bi6 octahedra, and edges with three equivalent Mg(1)Bi4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-58°. Sm(1) is bonded to six equivalent Bi(1) atoms to form SmBi6 octahedra that share corners with twelve equivalent Mg(1)Bi4 tetrahedra, edges with six equivalent Sm(1)Bi6 octahedra, and edges with six equivalent Mg(1)Bi4 tetrahedra. Bi(1) is bonded to four equivalent Mg(1) and three equivalent Sm(1) atoms to form a mixture of distorted corner and edge-sharing BiSm3Mg4 pentagonal bipyramids. is represented by the CIF file [CIF]
data_Sm(MgBi)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.870
_cell_length_b   4.870
_cell_length_c   7.406
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   152.090
_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
  Sm  Sm0  1  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.667  0.333  0.643  1.0
  Mg  Mg2  1  0.333  0.667  0.357  1.0
  Bi  Bi3  1  0.667  0.333  0.240  1.0
  Bi  Bi4  1  0.333  0.667  0.760  1.0
[/CIF]
.
The compound described by SmMg2Bi2 crystallizes in the trigonal P-3m1 space group. Mg(1) is bonded to four equivalent Bi(1) atoms to form MgBi4 tetrahedra that share corners with six equivalent Sm(1)Bi6 octahedra, corners with six equivalent Mg(1)Bi4 tetrahedra, edges with three equivalent Sm(1)Bi6 octahedra, and edges with three equivalent Mg(1)Bi4 tetrahedra. The corner-sharing octahedral tilt angles range from 15-58°. Sm(1) is bonded to six equivalent Bi(1) atoms to form SmBi6 octahedra that share corners with twelve equivalent Mg(1)Bi4 tetrahedra, edges with six equivalent Sm(1)Bi6 octahedra, and edges with six equivalent Mg(1)Bi4 tetrahedra. Bi(1) is bonded to four equivalent Mg(1) and three equivalent Sm(1) atoms to form a mixture of distorted corner and edge-sharing BiSm3Mg4 pentagonal bipyramids. is represented by the CIF file [CIF]
data_Sm(MgBi)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.870
_cell_length_b   4.870
_cell_length_c   7.406
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   152.090
_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
  Sm  Sm0  1  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.667  0.333  0.643  1.0
  Mg  Mg2  1  0.333  0.667  0.357  1.0
  Bi  Bi3  1  0.667  0.333  0.240  1.0
  Bi  Bi4  1  0.333  0.667  0.760  1.0
[/CIF]
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