The material structure described by MgCd2 crystallizes in the trigonal R32 space group. Mg(1) is bonded to three equivalent Mg(1), three equivalent Cd(2), and six equivalent Cd(1) atoms to form distorted MgMg3Cd9 cuboctahedra that share corners with six equivalent Cd(2)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(1)Mg3Cd9 cuboctahedra, edges with six equivalent Mg(1)Mg3Cd9 cuboctahedra, edges with twelve equivalent Cd(1)Mg4Cd8 cuboctahedra, faces with four equivalent Mg(1)Mg3Cd9 cuboctahedra, faces with four equivalent Cd(2)Mg6Cd6 cuboctahedra, and faces with twelve equivalent Cd(1)Mg4Cd8 cuboctahedra. There are four inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to four equivalent Mg(1), two equivalent Cd(2), and six equivalent Cd(1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with eighteen Cd(1,1,1)Mg4Cd8 cuboctahedra; edges with four equivalent Cd(2)Mg6Cd6 cuboctahedra; edges with six equivalent Cd(1)Mg4Cd8 cuboctahedra; edges with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; faces with four equivalent Cd(2)Mg6Cd6 cuboctahedra; faces with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; and faces with eight Cd(1,1)Mg4Cd8 cuboctahedra. In the second Cd site, Cd(2) is bonded to six equivalent Mg(1) and six equivalent Cd(1) atoms to form CdMg6Cd6 cuboctahedra that share corners with six equivalent Cd(2)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(1)Mg3Cd9 cuboctahedra, edges with six equivalent Cd(2)Mg6Cd6 cuboctahedra, edges with twelve equivalent Cd(1)Mg4Cd8 cuboctahedra, faces with eight equivalent Mg(1)Mg3Cd9 cuboctahedra, and faces with twelve equivalent Cd(1)Mg4Cd8 cuboctahedra. In the third Cd site, Cd(1) is bonded to four equivalent Mg(1), two equivalent Cd(2), and six equivalent Cd(1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with eighteen Cd(1,1)Mg4Cd8 cuboctahedra; edges with four equivalent Cd(2)Mg6Cd6 cuboctahedra; edges with six equivalent Cd(1)Mg4Cd8 cuboctahedra; edges with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; faces with four equivalent Cd(2)Mg6Cd6 cuboctahedra; faces with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; and faces with eight Cd(1,1)Mg4Cd8 cuboctahedra. In the fourth Cd site, Cd(1) is bonded to four equivalent Mg(1); two equivalent Cd(2); and six Cd(1,1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with eighteen Cd(1,1,1)Mg4Cd8 cuboctahedra; edges with four equivalent Cd(2)Mg6Cd6 cuboctahedra; edges with six equivalent Cd(1)Mg4Cd8 cuboctahedra; edges with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; faces with four equivalent Cd(2)Mg6Cd6 cuboctahedra; faces with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; and faces with eight Cd(1,1,1)Mg4Cd8 cuboctahedra. is represented by the CIF file [CIF]
data_MgCd2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.409
_cell_length_b   5.409
_cell_length_c   5.922
_cell_angle_alpha   62.823
_cell_angle_beta   62.823
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   127.498
_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
  Cd  Cd0  1  0.333  1.000  0.000  1.0
  Cd  Cd1  1  0.667  0.333  1.000  1.0
  Cd  Cd2  1  0.500  0.500  0.500  1.0
  Cd  Cd3  1  0.000  0.667  0.000  1.0
  Mg  Mg4  1  0.167  0.167  0.499  1.0
  Mg  Mg5  1  0.833  0.833  0.501  1.0
[/CIF]
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The material structure described by MgCd2 crystallizes in the trigonal R32 space group. Mg(1) is bonded to three equivalent Mg(1), three equivalent Cd(2), and six equivalent Cd(1) atoms to form distorted MgMg3Cd9 cuboctahedra that share corners with six equivalent Cd(2)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(1)Mg3Cd9 cuboctahedra, edges with six equivalent Mg(1)Mg3Cd9 cuboctahedra, edges with twelve equivalent Cd(1)Mg4Cd8 cuboctahedra, faces with four equivalent Mg(1)Mg3Cd9 cuboctahedra, faces with four equivalent Cd(2)Mg6Cd6 cuboctahedra, and faces with twelve equivalent Cd(1)Mg4Cd8 cuboctahedra. There are four inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to four equivalent Mg(1), two equivalent Cd(2), and six equivalent Cd(1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with eighteen Cd(1,1,1)Mg4Cd8 cuboctahedra; edges with four equivalent Cd(2)Mg6Cd6 cuboctahedra; edges with six equivalent Cd(1)Mg4Cd8 cuboctahedra; edges with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; faces with four equivalent Cd(2)Mg6Cd6 cuboctahedra; faces with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; and faces with eight Cd(1,1)Mg4Cd8 cuboctahedra. In the second Cd site, Cd(2) is bonded to six equivalent Mg(1) and six equivalent Cd(1) atoms to form CdMg6Cd6 cuboctahedra that share corners with six equivalent Cd(2)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(1)Mg3Cd9 cuboctahedra, edges with six equivalent Cd(2)Mg6Cd6 cuboctahedra, edges with twelve equivalent Cd(1)Mg4Cd8 cuboctahedra, faces with eight equivalent Mg(1)Mg3Cd9 cuboctahedra, and faces with twelve equivalent Cd(1)Mg4Cd8 cuboctahedra. In the third Cd site, Cd(1) is bonded to four equivalent Mg(1), two equivalent Cd(2), and six equivalent Cd(1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with eighteen Cd(1,1)Mg4Cd8 cuboctahedra; edges with four equivalent Cd(2)Mg6Cd6 cuboctahedra; edges with six equivalent Cd(1)Mg4Cd8 cuboctahedra; edges with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; faces with four equivalent Cd(2)Mg6Cd6 cuboctahedra; faces with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; and faces with eight Cd(1,1)Mg4Cd8 cuboctahedra. In the fourth Cd site, Cd(1) is bonded to four equivalent Mg(1); two equivalent Cd(2); and six Cd(1,1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with eighteen Cd(1,1,1)Mg4Cd8 cuboctahedra; edges with four equivalent Cd(2)Mg6Cd6 cuboctahedra; edges with six equivalent Cd(1)Mg4Cd8 cuboctahedra; edges with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; faces with four equivalent Cd(2)Mg6Cd6 cuboctahedra; faces with eight equivalent Mg(1)Mg3Cd9 cuboctahedra; and faces with eight Cd(1,1,1)Mg4Cd8 cuboctahedra. is represented by the CIF file [CIF]
data_MgCd2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.409
_cell_length_b   5.409
_cell_length_c   5.922
_cell_angle_alpha   62.823
_cell_angle_beta   62.823
_cell_angle_gamma   60.000
_symmetry_Int_Tables_number   1
_cell_volume   127.498
_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
  Cd  Cd0  1  0.333  1.000  0.000  1.0
  Cd  Cd1  1  0.667  0.333  1.000  1.0
  Cd  Cd2  1  0.500  0.500  0.500  1.0
  Cd  Cd3  1  0.000  0.667  0.000  1.0
  Mg  Mg4  1  0.167  0.167  0.499  1.0
  Mg  Mg5  1  0.833  0.833  0.501  1.0
[/CIF]
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