The structure described by MgCe2 crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded to six equivalent Mg(1), two equivalent Ce(2), and four equivalent Ce(1) atoms to form MgCe6Mg6 cuboctahedra that share corners with six equivalent Mg(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with four equivalent Mg(1)Ce6Mg6 cuboctahedra, edges with eleven equivalent Ce(2)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce10Mg2 cuboctahedra, faces with eight equivalent Mg(1)Ce6Mg6 cuboctahedra, and faces with eight equivalent Ce(1)Ce8Mg4 cuboctahedra. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to four equivalent Mg(1), two equivalent Ce(1), and six equivalent Ce(2) atoms to form CeCe8Mg4 cuboctahedra that share corners with six equivalent Mg(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with three equivalent Mg(1)Ce6Mg6 cuboctahedra, edges with seven equivalent Ce(2)Ce10Mg2 cuboctahedra, edges with eight equivalent Ce(1)Ce8Mg4 cuboctahedra, faces with six equivalent Ce(2)Ce10Mg2 cuboctahedra, faces with six equivalent Ce(1)Ce8Mg4 cuboctahedra, and faces with eight equivalent Mg(1)Ce6Mg6 cuboctahedra. In the second Ce site, Ce(2) is bonded to two equivalent Mg(1), four equivalent Ce(2), and six equivalent Ce(1) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with seven equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with eleven equivalent Mg(1)Ce6Mg6 cuboctahedra, faces with four equivalent Mg(1)Ce6Mg6 cuboctahedra, faces with six equivalent Ce(1)Ce8Mg4 cuboctahedra, and faces with ten equivalent Ce(2)Ce10Mg2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.594
_cell_length_b   9.594
_cell_length_c   5.175
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   161.321
_symmetry_Int_Tables_number   1
_cell_volume   152.538
_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
  Ce  Ce0  1  0.603  0.397  0.250  1.0
  Ce  Ce1  1  0.929  0.071  0.250  1.0
  Ce  Ce2  1  0.071  0.929  0.750  1.0
  Ce  Ce3  1  0.397  0.603  0.750  1.0
  Mg  Mg4  1  0.271  0.729  0.250  1.0
  Mg  Mg5  1  0.729  0.271  0.750  1.0
[/CIF]
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The structure described by MgCe2 crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded to six equivalent Mg(1), two equivalent Ce(2), and four equivalent Ce(1) atoms to form MgCe6Mg6 cuboctahedra that share corners with six equivalent Mg(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with four equivalent Mg(1)Ce6Mg6 cuboctahedra, edges with eleven equivalent Ce(2)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce10Mg2 cuboctahedra, faces with eight equivalent Mg(1)Ce6Mg6 cuboctahedra, and faces with eight equivalent Ce(1)Ce8Mg4 cuboctahedra. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to four equivalent Mg(1), two equivalent Ce(1), and six equivalent Ce(2) atoms to form CeCe8Mg4 cuboctahedra that share corners with six equivalent Mg(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with three equivalent Mg(1)Ce6Mg6 cuboctahedra, edges with seven equivalent Ce(2)Ce10Mg2 cuboctahedra, edges with eight equivalent Ce(1)Ce8Mg4 cuboctahedra, faces with six equivalent Ce(2)Ce10Mg2 cuboctahedra, faces with six equivalent Ce(1)Ce8Mg4 cuboctahedra, and faces with eight equivalent Mg(1)Ce6Mg6 cuboctahedra. In the second Ce site, Ce(2) is bonded to two equivalent Mg(1), four equivalent Ce(2), and six equivalent Ce(1) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with seven equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with eleven equivalent Mg(1)Ce6Mg6 cuboctahedra, faces with four equivalent Mg(1)Ce6Mg6 cuboctahedra, faces with six equivalent Ce(1)Ce8Mg4 cuboctahedra, and faces with ten equivalent Ce(2)Ce10Mg2 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ce2Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.594
_cell_length_b   9.594
_cell_length_c   5.175
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   161.321
_symmetry_Int_Tables_number   1
_cell_volume   152.538
_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
  Ce  Ce0  1  0.603  0.397  0.250  1.0
  Ce  Ce1  1  0.929  0.071  0.250  1.0
  Ce  Ce2  1  0.071  0.929  0.750  1.0
  Ce  Ce3  1  0.397  0.603  0.750  1.0
  Mg  Mg4  1  0.271  0.729  0.250  1.0
  Mg  Mg5  1  0.729  0.271  0.750  1.0
[/CIF]
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