The structure described by BiMg2 crystallizes in the hexagonal P-62m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), six equivalent Mg(1), and four equivalent Bi(1) atoms to form distorted MgMg8Bi4 cuboctahedra that share corners with eighteen equivalent Mg(1)Mg8Bi4 cuboctahedra, edges with four equivalent Mg(2)Mg6Bi6 cuboctahedra, edges with six equivalent Mg(1)Mg8Bi4 cuboctahedra, edges with eight equivalent Bi(1)Mg9Bi3 cuboctahedra, faces with four equivalent Mg(2)Mg6Bi6 cuboctahedra, faces with eight equivalent Mg(1)Mg8Bi4 cuboctahedra, and faces with eight equivalent Bi(1)Mg9Bi3 cuboctahedra. In the second Mg site, Mg(2) is bonded to six equivalent Mg(1) and six equivalent Bi(1) atoms to form distorted MgMg6Bi6 cuboctahedra that share corners with eighteen equivalent Bi(1)Mg9Bi3 cuboctahedra, edges with six equivalent Mg(2)Mg6Bi6 cuboctahedra, edges with twelve equivalent Mg(1)Mg8Bi4 cuboctahedra, faces with two equivalent Mg(2)Mg6Bi6 cuboctahedra, faces with six equivalent Bi(1)Mg9Bi3 cuboctahedra, and faces with twelve equivalent Mg(1)Mg8Bi4 cuboctahedra. Bi(1) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Bi(1) atoms to form distorted BiMg9Bi3 cuboctahedra that share corners with nine equivalent Mg(2)Mg6Bi6 cuboctahedra, corners with nine equivalent Bi(1)Mg9Bi3 cuboctahedra, edges with six equivalent Bi(1)Mg9Bi3 cuboctahedra, edges with twelve equivalent Mg(1)Mg8Bi4 cuboctahedra, faces with three equivalent Mg(2)Mg6Bi6 cuboctahedra, faces with five equivalent Bi(1)Mg9Bi3 cuboctahedra, and faces with twelve equivalent Mg(1)Mg8Bi4 cuboctahedra. is represented by the CIF file [CIF]
data_Mg2Bi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.787
_cell_length_b   5.787
_cell_length_c   5.423
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   157.303
_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
  Mg  Mg0  1  0.670  0.000  0.000  1.0
  Mg  Mg1  1  0.000  0.670  0.000  1.0
  Mg  Mg2  1  0.330  0.330  0.000  1.0
  Mg  Mg3  1  0.000  0.000  0.500  1.0
  Bi  Bi4  1  0.333  0.667  0.500  1.0
  Bi  Bi5  1  0.667  0.333  0.500  1.0
[/CIF]
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The structure described by BiMg2 crystallizes in the hexagonal P-62m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), six equivalent Mg(1), and four equivalent Bi(1) atoms to form distorted MgMg8Bi4 cuboctahedra that share corners with eighteen equivalent Mg(1)Mg8Bi4 cuboctahedra, edges with four equivalent Mg(2)Mg6Bi6 cuboctahedra, edges with six equivalent Mg(1)Mg8Bi4 cuboctahedra, edges with eight equivalent Bi(1)Mg9Bi3 cuboctahedra, faces with four equivalent Mg(2)Mg6Bi6 cuboctahedra, faces with eight equivalent Mg(1)Mg8Bi4 cuboctahedra, and faces with eight equivalent Bi(1)Mg9Bi3 cuboctahedra. In the second Mg site, Mg(2) is bonded to six equivalent Mg(1) and six equivalent Bi(1) atoms to form distorted MgMg6Bi6 cuboctahedra that share corners with eighteen equivalent Bi(1)Mg9Bi3 cuboctahedra, edges with six equivalent Mg(2)Mg6Bi6 cuboctahedra, edges with twelve equivalent Mg(1)Mg8Bi4 cuboctahedra, faces with two equivalent Mg(2)Mg6Bi6 cuboctahedra, faces with six equivalent Bi(1)Mg9Bi3 cuboctahedra, and faces with twelve equivalent Mg(1)Mg8Bi4 cuboctahedra. Bi(1) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Bi(1) atoms to form distorted BiMg9Bi3 cuboctahedra that share corners with nine equivalent Mg(2)Mg6Bi6 cuboctahedra, corners with nine equivalent Bi(1)Mg9Bi3 cuboctahedra, edges with six equivalent Bi(1)Mg9Bi3 cuboctahedra, edges with twelve equivalent Mg(1)Mg8Bi4 cuboctahedra, faces with three equivalent Mg(2)Mg6Bi6 cuboctahedra, faces with five equivalent Bi(1)Mg9Bi3 cuboctahedra, and faces with twelve equivalent Mg(1)Mg8Bi4 cuboctahedra. is represented by the CIF file [CIF]
data_Mg2Bi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.787
_cell_length_b   5.787
_cell_length_c   5.423
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   157.303
_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
  Mg  Mg0  1  0.670  0.000  0.000  1.0
  Mg  Mg1  1  0.000  0.670  0.000  1.0
  Mg  Mg2  1  0.330  0.330  0.000  1.0
  Mg  Mg3  1  0.000  0.000  0.500  1.0
  Bi  Bi4  1  0.333  0.667  0.500  1.0
  Bi  Bi5  1  0.667  0.333  0.500  1.0
[/CIF]
.