The material described by MgCd2 crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded to four equivalent Cd(2) and six equivalent Cd(1) atoms to form distorted MgCd10 cuboctahedra that share corners with four equivalent Mg(1)Cd10 cuboctahedra, corners with eight equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra,  an edgeedge with one Cd(2)Mg4Cd8 cuboctahedra,  an edgeedge with one Cd(1)Mg6Cd6 cuboctahedra, edges with eight equivalent Mg(1)Cd10 cuboctahedra, faces with six equivalent Mg(1)Cd10 cuboctahedra, faces with six equivalent Cd(1)Mg6Cd6 cuboctahedra, and faces with eight equivalent Cd(2)Mg4Cd8 cuboctahedra. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to six equivalent Mg(1), two equivalent Cd(2), and four equivalent Cd(1) atoms to form distorted CdMg6Cd6 cuboctahedra that share corners with six equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with six equivalent Cd(1)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(1)Cd10 cuboctahedra,  an edgeedge with one Mg(1)Cd10 cuboctahedra, edges with eleven equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with four equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with six equivalent Mg(1)Cd10 cuboctahedra, and faces with ten equivalent Cd(1)Mg6Cd6 cuboctahedra. In the second Cd site, Cd(2) is bonded to four equivalent Mg(1), two equivalent Cd(1), and six equivalent Cd(2) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with six equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with six equivalent Cd(1)Mg6Cd6 cuboctahedra, corners with eight equivalent Mg(1)Cd10 cuboctahedra,  an edgeedge with one Mg(1)Cd10 cuboctahedra, edges with four equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with eleven equivalent Cd(1)Mg6Cd6 cuboctahedra, faces with four equivalent Cd(1)Mg6Cd6 cuboctahedra, faces with eight equivalent Mg(1)Cd10 cuboctahedra, and faces with eight equivalent Cd(2)Mg4Cd8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCd2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.203
_cell_length_b   5.019
_cell_length_c   8.018
_cell_angle_alpha   90.000
_cell_angle_beta   101.523
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   126.289
_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  0.445  0.750  0.891  1.0
  Cd  Cd1  1  0.778  0.750  0.556  1.0
  Cd  Cd2  1  0.222  0.250  0.444  1.0
  Cd  Cd3  1  0.555  0.250  0.109  1.0
  Mg  Mg4  1  0.110  0.750  0.220  1.0
  Mg  Mg5  1  0.890  0.250  0.780  1.0
[/CIF]
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The material described by MgCd2 crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded to four equivalent Cd(2) and six equivalent Cd(1) atoms to form distorted MgCd10 cuboctahedra that share corners with four equivalent Mg(1)Cd10 cuboctahedra, corners with eight equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with twelve equivalent Cd(1)Mg6Cd6 cuboctahedra,  an edgeedge with one Cd(2)Mg4Cd8 cuboctahedra,  an edgeedge with one Cd(1)Mg6Cd6 cuboctahedra, edges with eight equivalent Mg(1)Cd10 cuboctahedra, faces with six equivalent Mg(1)Cd10 cuboctahedra, faces with six equivalent Cd(1)Mg6Cd6 cuboctahedra, and faces with eight equivalent Cd(2)Mg4Cd8 cuboctahedra. There are two inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to six equivalent Mg(1), two equivalent Cd(2), and four equivalent Cd(1) atoms to form distorted CdMg6Cd6 cuboctahedra that share corners with six equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with six equivalent Cd(1)Mg6Cd6 cuboctahedra, corners with twelve equivalent Mg(1)Cd10 cuboctahedra,  an edgeedge with one Mg(1)Cd10 cuboctahedra, edges with eleven equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with four equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with six equivalent Mg(1)Cd10 cuboctahedra, and faces with ten equivalent Cd(1)Mg6Cd6 cuboctahedra. In the second Cd site, Cd(2) is bonded to four equivalent Mg(1), two equivalent Cd(1), and six equivalent Cd(2) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with six equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with six equivalent Cd(1)Mg6Cd6 cuboctahedra, corners with eight equivalent Mg(1)Cd10 cuboctahedra,  an edgeedge with one Mg(1)Cd10 cuboctahedra, edges with four equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with eleven equivalent Cd(1)Mg6Cd6 cuboctahedra, faces with four equivalent Cd(1)Mg6Cd6 cuboctahedra, faces with eight equivalent Mg(1)Cd10 cuboctahedra, and faces with eight equivalent Cd(2)Mg4Cd8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgCd2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.203
_cell_length_b   5.019
_cell_length_c   8.018
_cell_angle_alpha   90.000
_cell_angle_beta   101.523
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   126.289
_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  0.445  0.750  0.891  1.0
  Cd  Cd1  1  0.778  0.750  0.556  1.0
  Cd  Cd2  1  0.222  0.250  0.444  1.0
  Cd  Cd3  1  0.555  0.250  0.109  1.0
  Mg  Mg4  1  0.110  0.750  0.220  1.0
  Mg  Mg5  1  0.890  0.250  0.780  1.0
[/CIF]
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