The compound described by Mg2Cd crystallizes in the hexagonal P-6m2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(1)Mg12 cuboctahedra, corners with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra, edges with six equivalent Mg(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(2)Mg9Cd3 cuboctahedra, faces with two equivalent Cd(1)Mg6Cd6 cuboctahedra, faces with six equivalent Mg(1)Mg12 cuboctahedra, and faces with twelve equivalent Mg(2)Mg9Cd3 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Mg(1), six equivalent Mg(2), and three equivalent Cd(1) atoms to form distorted MgMg9Cd3 cuboctahedra that share corners with six equivalent Mg(3)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(2)Mg9Cd3 cuboctahedra, edges with six equivalent Mg(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Mg9Cd3 cuboctahedra, edges with six equivalent Cd(1)Mg6Cd6 cuboctahedra,  a faceface with one Mg(3)Mg6Cd6 cuboctahedra, faces with six equivalent Mg(1)Mg12 cuboctahedra, faces with six equivalent Cd(1)Mg6Cd6 cuboctahedra, and faces with seven equivalent Mg(2)Mg9Cd3 cuboctahedra. In the third Mg site, Mg(3) is bonded to six equivalent Mg(3) and six equivalent Cd(1) atoms to form MgMg6Cd6 cuboctahedra that share corners with six equivalent Mg(3)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(2)Mg9Cd3 cuboctahedra, edges with six equivalent Mg(3)Mg6Cd6 cuboctahedra, edges with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra, faces with two equivalent Mg(2)Mg9Cd3 cuboctahedra, faces with six equivalent Mg(3)Mg6Cd6 cuboctahedra, and faces with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra. Cd(1) is bonded to three equivalent Mg(2), three equivalent Mg(3), and six equivalent Cd(1) atoms to form CdMg6Cd6 cuboctahedra that share corners with six equivalent Mg(1)Mg12 cuboctahedra, corners with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra, edges with six equivalent Mg(3)Mg6Cd6 cuboctahedra, edges with six equivalent Mg(2)Mg9Cd3 cuboctahedra, edges with six equivalent Cd(1)Mg6Cd6 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra, faces with six equivalent Mg(3)Mg6Cd6 cuboctahedra, faces with six equivalent Mg(2)Mg9Cd3 cuboctahedra, and faces with seven equivalent Cd(1)Mg6Cd6 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Cd
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.150
_cell_length_b   3.150
_cell_length_c   15.694
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   134.842
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.667  0.333  0.831  1.0
  Mg  Mg2  1  0.667  0.333  0.500  1.0
  Mg  Mg3  1  0.667  0.333  0.169  1.0
  Cd  Cd4  1  0.000  0.000  0.666  1.0
  Cd  Cd5  1  0.000  0.000  0.334  1.0
[/CIF]
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The compound described by Mg2Cd crystallizes in the hexagonal P-6m2 space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(1)Mg12 cuboctahedra, corners with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra, edges with six equivalent Mg(1)Mg12 cuboctahedra, edges with twelve equivalent Mg(2)Mg9Cd3 cuboctahedra, faces with two equivalent Cd(1)Mg6Cd6 cuboctahedra, faces with six equivalent Mg(1)Mg12 cuboctahedra, and faces with twelve equivalent Mg(2)Mg9Cd3 cuboctahedra. In the second Mg site, Mg(2) is bonded to three equivalent Mg(1), six equivalent Mg(2), and three equivalent Cd(1) atoms to form distorted MgMg9Cd3 cuboctahedra that share corners with six equivalent Mg(3)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(2)Mg9Cd3 cuboctahedra, edges with six equivalent Mg(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Mg9Cd3 cuboctahedra, edges with six equivalent Cd(1)Mg6Cd6 cuboctahedra,  a faceface with one Mg(3)Mg6Cd6 cuboctahedra, faces with six equivalent Mg(1)Mg12 cuboctahedra, faces with six equivalent Cd(1)Mg6Cd6 cuboctahedra, and faces with seven equivalent Mg(2)Mg9Cd3 cuboctahedra. In the third Mg site, Mg(3) is bonded to six equivalent Mg(3) and six equivalent Cd(1) atoms to form MgMg6Cd6 cuboctahedra that share corners with six equivalent Mg(3)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(2)Mg9Cd3 cuboctahedra, edges with six equivalent Mg(3)Mg6Cd6 cuboctahedra, edges with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra, faces with two equivalent Mg(2)Mg9Cd3 cuboctahedra, faces with six equivalent Mg(3)Mg6Cd6 cuboctahedra, and faces with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra. Cd(1) is bonded to three equivalent Mg(2), three equivalent Mg(3), and six equivalent Cd(1) atoms to form CdMg6Cd6 cuboctahedra that share corners with six equivalent Mg(1)Mg12 cuboctahedra, corners with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra, edges with six equivalent Mg(3)Mg6Cd6 cuboctahedra, edges with six equivalent Mg(2)Mg9Cd3 cuboctahedra, edges with six equivalent Cd(1)Mg6Cd6 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra, faces with six equivalent Mg(3)Mg6Cd6 cuboctahedra, faces with six equivalent Mg(2)Mg9Cd3 cuboctahedra, and faces with seven equivalent Cd(1)Mg6Cd6 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Cd
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.150
_cell_length_b   3.150
_cell_length_c   15.694
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   134.842
_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  0.000  0.000  0.000  1.0
  Mg  Mg1  1  0.667  0.333  0.831  1.0
  Mg  Mg2  1  0.667  0.333  0.500  1.0
  Mg  Mg3  1  0.667  0.333  0.169  1.0
  Cd  Cd4  1  0.000  0.000  0.666  1.0
  Cd  Cd5  1  0.000  0.000  0.334  1.0
[/CIF]
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