The compound described by MgCd3 crystallizes in the orthorhombic Pmm2 space group. Mg(1) is bonded to two equivalent Cd(1), four equivalent Cd(2), and four equivalent Cd(3) atoms to form distorted MgCd10 cuboctahedra that share corners with four equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with eight equivalent Mg(1)Cd10 cuboctahedra, corners with twelve equivalent Cd(3)Mg4Cd8 cuboctahedra, edges with two equivalent Mg(1)Cd10 cuboctahedra, edges with four equivalent Cd(1)Mg2Cd10 cuboctahedra, edges with four equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with four equivalent Mg(1)Cd10 cuboctahedra, faces with four equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with four equivalent Cd(3)Mg4Cd8 cuboctahedra, and faces with eight equivalent Cd(1)Mg2Cd10 cuboctahedra. There are three inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to two equivalent Mg(1), two equivalent Cd(1), four equivalent Cd(2), and four equivalent Cd(3) atoms to form distorted CdMg2Cd10 cuboctahedra that share corners with eight equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with ten equivalent Cd(1)Mg2Cd10 cuboctahedra, edges with two equivalent Cd(1)Mg2Cd10 cuboctahedra, edges with four equivalent Mg(1)Cd10 cuboctahedra, edges with four equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with eight equivalent Cd(3)Mg4Cd8 cuboctahedra, faces with four equivalent Cd(1)Mg2Cd10 cuboctahedra, faces with four equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with four equivalent Cd(3)Mg4Cd8 cuboctahedra, and faces with eight equivalent Mg(1)Cd10 cuboctahedra. In the second Cd site, Cd(2) is bonded to four equivalent Mg(1), two equivalent Cd(2), two equivalent Cd(3), and four equivalent Cd(1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with four equivalent Mg(1)Cd10 cuboctahedra, corners with eight equivalent Cd(1)Mg2Cd10 cuboctahedra, corners with ten equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with two equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with four equivalent Mg(1)Cd10 cuboctahedra, edges with four equivalent Cd(1)Mg2Cd10 cuboctahedra, edges with four equivalent Cd(3)Mg4Cd8 cuboctahedra, faces with four equivalent Mg(1)Cd10 cuboctahedra, faces with four equivalent Cd(1)Mg2Cd10 cuboctahedra, faces with four equivalent Cd(2)Mg4Cd8 cuboctahedra, and faces with eight equivalent Cd(3)Mg4Cd8 cuboctahedra. In the third Cd site, Cd(3) is bonded to four equivalent Mg(1), two equivalent Cd(2), two equivalent Cd(3), and four equivalent Cd(1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with ten equivalent Cd(3)Mg4Cd8 cuboctahedra, corners with twelve equivalent Mg(1)Cd10 cuboctahedra, edges with two equivalent Cd(3)Mg4Cd8 cuboctahedra, edges with four equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with eight equivalent Cd(1)Mg2Cd10 cuboctahedra, faces with four equivalent Mg(1)Cd10 cuboctahedra, faces with four equivalent Cd(1)Mg2Cd10 cuboctahedra, faces with four equivalent Cd(3)Mg4Cd8 cuboctahedra, and faces with eight equivalent Cd(2)Mg4Cd8 cuboctahedra. is represented by the CIF file [CIF]
data_MgCd3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.229
_cell_length_b   4.970
_cell_length_c   5.304
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   85.116
_cell_formula_units_Z   1
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  0.500  0.335  1.0
  Cd  Cd1  1  0.000  0.000  0.004  1.0
  Cd  Cd2  1  0.500  0.000  0.498  1.0
  Cd  Cd3  1  0.500  0.500  0.830  1.0
[/CIF]
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The compound described by MgCd3 crystallizes in the orthorhombic Pmm2 space group. Mg(1) is bonded to two equivalent Cd(1), four equivalent Cd(2), and four equivalent Cd(3) atoms to form distorted MgCd10 cuboctahedra that share corners with four equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with eight equivalent Mg(1)Cd10 cuboctahedra, corners with twelve equivalent Cd(3)Mg4Cd8 cuboctahedra, edges with two equivalent Mg(1)Cd10 cuboctahedra, edges with four equivalent Cd(1)Mg2Cd10 cuboctahedra, edges with four equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with four equivalent Mg(1)Cd10 cuboctahedra, faces with four equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with four equivalent Cd(3)Mg4Cd8 cuboctahedra, and faces with eight equivalent Cd(1)Mg2Cd10 cuboctahedra. There are three inequivalent Cd sites. In the first Cd site, Cd(1) is bonded to two equivalent Mg(1), two equivalent Cd(1), four equivalent Cd(2), and four equivalent Cd(3) atoms to form distorted CdMg2Cd10 cuboctahedra that share corners with eight equivalent Cd(2)Mg4Cd8 cuboctahedra, corners with ten equivalent Cd(1)Mg2Cd10 cuboctahedra, edges with two equivalent Cd(1)Mg2Cd10 cuboctahedra, edges with four equivalent Mg(1)Cd10 cuboctahedra, edges with four equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with eight equivalent Cd(3)Mg4Cd8 cuboctahedra, faces with four equivalent Cd(1)Mg2Cd10 cuboctahedra, faces with four equivalent Cd(2)Mg4Cd8 cuboctahedra, faces with four equivalent Cd(3)Mg4Cd8 cuboctahedra, and faces with eight equivalent Mg(1)Cd10 cuboctahedra. In the second Cd site, Cd(2) is bonded to four equivalent Mg(1), two equivalent Cd(2), two equivalent Cd(3), and four equivalent Cd(1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with four equivalent Mg(1)Cd10 cuboctahedra, corners with eight equivalent Cd(1)Mg2Cd10 cuboctahedra, corners with ten equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with two equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with four equivalent Mg(1)Cd10 cuboctahedra, edges with four equivalent Cd(1)Mg2Cd10 cuboctahedra, edges with four equivalent Cd(3)Mg4Cd8 cuboctahedra, faces with four equivalent Mg(1)Cd10 cuboctahedra, faces with four equivalent Cd(1)Mg2Cd10 cuboctahedra, faces with four equivalent Cd(2)Mg4Cd8 cuboctahedra, and faces with eight equivalent Cd(3)Mg4Cd8 cuboctahedra. In the third Cd site, Cd(3) is bonded to four equivalent Mg(1), two equivalent Cd(2), two equivalent Cd(3), and four equivalent Cd(1) atoms to form distorted CdMg4Cd8 cuboctahedra that share corners with ten equivalent Cd(3)Mg4Cd8 cuboctahedra, corners with twelve equivalent Mg(1)Cd10 cuboctahedra, edges with two equivalent Cd(3)Mg4Cd8 cuboctahedra, edges with four equivalent Cd(2)Mg4Cd8 cuboctahedra, edges with eight equivalent Cd(1)Mg2Cd10 cuboctahedra, faces with four equivalent Mg(1)Cd10 cuboctahedra, faces with four equivalent Cd(1)Mg2Cd10 cuboctahedra, faces with four equivalent Cd(3)Mg4Cd8 cuboctahedra, and faces with eight equivalent Cd(2)Mg4Cd8 cuboctahedra. is represented by the CIF file [CIF]
data_MgCd3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.229
_cell_length_b   4.970
_cell_length_c   5.304
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   85.116
_cell_formula_units_Z   1
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  0.500  0.335  1.0
  Cd  Cd1  1  0.000  0.000  0.004  1.0
  Cd  Cd2  1  0.500  0.000  0.498  1.0
  Cd  Cd3  1  0.500  0.500  0.830  1.0
[/CIF]
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