The crystal structure described by MgCd2 is beta-derived structured and crystallizes in the hexagonal P-6m2 space group. Mg(1) is bonded to six equivalent Mg(1), three equivalent Cd(2), and three equivalent Cd(3) atoms to form MgMg6Cd6 cuboctahedra that share corners with six equivalent Cd(1)Cd12 cuboctahedra, corners with twelve equivalent Mg(1)Mg6Cd6 cuboctahedra, edges with six equivalent Mg(1)Mg6Cd6 cuboctahedra, edges with six equivalent Cd(2)Mg3Cd9 cuboctahedra, edges with six equivalent Cd(3)Mg6Cd6 cuboctahedra,  a faceface with one Cd(1)Cd12 cuboctahedra, faces with six equivalent Cd(2)Mg3Cd9 cuboctahedra, faces with six equivalent Cd(3)Mg6Cd6 cuboctahedra, and faces with seven equivalent Mg(1)Mg6Cd6 cuboctahedra. There are three inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to six equivalent Cd(1) and six equivalent Cd(2) atoms to form CdCd12 cuboctahedra that share corners with six equivalent Cd(1)Cd12 cuboctahedra, corners with twelve equivalent Mg(1)Mg6Cd6 cuboctahedra, edges with six equivalent Cd(1)Cd12 cuboctahedra, edges with twelve equivalent Cd(2)Mg3Cd9 cuboctahedra, faces with two equivalent Mg(1)Mg6Cd6 cuboctahedra, faces with six equivalent Cd(1)Cd12 cuboctahedra, and faces with twelve equivalent Cd(2)Mg3Cd9 cuboctahedra. In the second Cd site, Cd(2) is bonded to three equivalent Mg(1), three equivalent Cd(1), and six equivalent Cd(2) atoms to form distorted CdMg3Cd9 cuboctahedra that share corners with six equivalent Cd(3)Mg6Cd6 cuboctahedra, corners with twelve equivalent Cd(2)Mg3Cd9 cuboctahedra, edges with six equivalent Mg(1)Mg6Cd6 cuboctahedra, edges with six equivalent Cd(1)Cd12 cuboctahedra, edges with six equivalent Cd(2)Mg3Cd9 cuboctahedra,  a faceface with one Cd(3)Mg6Cd6 cuboctahedra, faces with six equivalent Mg(1)Mg6Cd6 cuboctahedra, faces with six equivalent Cd(1)Cd12 cuboctahedra, and faces with seven equivalent Cd(2)Mg3Cd9 cuboctahedra. In the third Cd site, Cd(3) is bonded to six equivalent Mg(1) and six equivalent Cd(3) atoms to form CdMg6Cd6 cuboctahedra that share corners with six equivalent Cd(3)Mg6Cd6 cuboctahedra, corners with twelve equivalent Cd(2)Mg3Cd9 cuboctahedra, edges with six equivalent Cd(3)Mg6Cd6 cuboctahedra, edges with twelve equivalent Mg(1)Mg6Cd6 cuboctahedra, faces with two equivalent Cd(2)Mg3Cd9 cuboctahedra, faces with six equivalent Cd(3)Mg6Cd6 cuboctahedra, and faces with twelve equivalent Mg(1)Mg6Cd6 cuboctahedra. is represented by the CIF card [CIF]
data_MgCd2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.121
_cell_length_b   3.121
_cell_length_c   15.959
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   134.606
_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  0.166  1.0
  Mg  Mg1  1  0.000  0.000  0.834  1.0
  Cd  Cd2  1  0.000  0.000  0.500  1.0
  Cd  Cd3  1  0.667  0.333  0.331  1.0
  Cd  Cd4  1  0.667  0.333  0.000  1.0
  Cd  Cd5  1  0.667  0.333  0.669  1.0
[/CIF]
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The crystal structure described by MgCd2 is beta-derived structured and crystallizes in the hexagonal P-6m2 space group. Mg(1) is bonded to six equivalent Mg(1), three equivalent Cd(2), and three equivalent Cd(3) atoms to form MgMg6Cd6 cuboctahedra that share corners with six equivalent Cd(1)Cd12 cuboctahedra, corners with twelve equivalent Mg(1)Mg6Cd6 cuboctahedra, edges with six equivalent Mg(1)Mg6Cd6 cuboctahedra, edges with six equivalent Cd(2)Mg3Cd9 cuboctahedra, edges with six equivalent Cd(3)Mg6Cd6 cuboctahedra,  a faceface with one Cd(1)Cd12 cuboctahedra, faces with six equivalent Cd(2)Mg3Cd9 cuboctahedra, faces with six equivalent Cd(3)Mg6Cd6 cuboctahedra, and faces with seven equivalent Mg(1)Mg6Cd6 cuboctahedra. There are three inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to six equivalent Cd(1) and six equivalent Cd(2) atoms to form CdCd12 cuboctahedra that share corners with six equivalent Cd(1)Cd12 cuboctahedra, corners with twelve equivalent Mg(1)Mg6Cd6 cuboctahedra, edges with six equivalent Cd(1)Cd12 cuboctahedra, edges with twelve equivalent Cd(2)Mg3Cd9 cuboctahedra, faces with two equivalent Mg(1)Mg6Cd6 cuboctahedra, faces with six equivalent Cd(1)Cd12 cuboctahedra, and faces with twelve equivalent Cd(2)Mg3Cd9 cuboctahedra. In the second Cd site, Cd(2) is bonded to three equivalent Mg(1), three equivalent Cd(1), and six equivalent Cd(2) atoms to form distorted CdMg3Cd9 cuboctahedra that share corners with six equivalent Cd(3)Mg6Cd6 cuboctahedra, corners with twelve equivalent Cd(2)Mg3Cd9 cuboctahedra, edges with six equivalent Mg(1)Mg6Cd6 cuboctahedra, edges with six equivalent Cd(1)Cd12 cuboctahedra, edges with six equivalent Cd(2)Mg3Cd9 cuboctahedra,  a faceface with one Cd(3)Mg6Cd6 cuboctahedra, faces with six equivalent Mg(1)Mg6Cd6 cuboctahedra, faces with six equivalent Cd(1)Cd12 cuboctahedra, and faces with seven equivalent Cd(2)Mg3Cd9 cuboctahedra. In the third Cd site, Cd(3) is bonded to six equivalent Mg(1) and six equivalent Cd(3) atoms to form CdMg6Cd6 cuboctahedra that share corners with six equivalent Cd(3)Mg6Cd6 cuboctahedra, corners with twelve equivalent Cd(2)Mg3Cd9 cuboctahedra, edges with six equivalent Cd(3)Mg6Cd6 cuboctahedra, edges with twelve equivalent Mg(1)Mg6Cd6 cuboctahedra, faces with two equivalent Cd(2)Mg3Cd9 cuboctahedra, faces with six equivalent Cd(3)Mg6Cd6 cuboctahedra, and faces with twelve equivalent Mg(1)Mg6Cd6 cuboctahedra. is represented by the CIF card [CIF]
data_MgCd2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.121
_cell_length_b   3.121
_cell_length_c   15.959
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   134.606
_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  0.166  1.0
  Mg  Mg1  1  0.000  0.000  0.834  1.0
  Cd  Cd2  1  0.000  0.000  0.500  1.0
  Cd  Cd3  1  0.667  0.333  0.331  1.0
  Cd  Cd4  1  0.667  0.333  0.000  1.0
  Cd  Cd5  1  0.667  0.333  0.669  1.0
[/CIF]
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