The compound described by MgCe3 is beta-derived structured and crystallizes in the orthorhombic Pmm2 space group. Mg(1) is bonded to two equivalent Mg(1), two equivalent Ce(1), four equivalent Ce(2), and four equivalent Ce(3) atoms to form MgCe10Mg2 cuboctahedra that share corners with eight equivalent Ce(3)Ce8Mg4 cuboctahedra, corners with ten equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with two equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(3)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(3)Ce8Mg4 cuboctahedra, and faces with eight equivalent Ce(1)Ce10Mg2 cuboctahedra. There are three inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to two equivalent Mg(1), two equivalent Ce(1), four equivalent Ce(2), and four equivalent Ce(3) atoms to form CeCe10Mg2 cuboctahedra that share corners with eight equivalent Ce(2)Ce8Mg4 cuboctahedra, corners with ten equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with two equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with four equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(3)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(3)Ce8Mg4 cuboctahedra, and faces with eight equivalent Mg(1)Ce10Mg2 cuboctahedra. In the second Ce site, Ce(2) is bonded to four equivalent Mg(1), two equivalent Ce(2), two equivalent Ce(3), and four equivalent Ce(1) atoms to form CeCe8Mg4 cuboctahedra that share corners with eight equivalent Ce(1)Ce10Mg2 cuboctahedra, corners with ten equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with two equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with four equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(3)Ce8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, and faces with eight equivalent Ce(3)Ce8Mg4 cuboctahedra. In the third Ce site, Ce(3) is bonded to four equivalent Mg(1), two equivalent Ce(2), two equivalent Ce(3), and four equivalent Ce(1) atoms to form CeCe8Mg4 cuboctahedra that share corners with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with ten equivalent Ce(3)Ce8Mg4 cuboctahedra, edges with two equivalent Ce(3)Ce8Mg4 cuboctahedra, edges with four equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(3)Ce8Mg4 cuboctahedra, and faces with eight equivalent Ce(2)Ce8Mg4 cuboctahedra. is represented by the CIF card [CIF]
data_Ce3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.254
_cell_length_b   5.492
_cell_length_c   5.938
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   106.117
_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
  Ce  Ce0  1  0.000  0.000  1.000  1.0
  Ce  Ce1  1  0.500  0.000  0.490  1.0
  Ce  Ce2  1  0.500  0.500  0.846  1.0
  Mg  Mg3  1  0.000  0.500  0.331  1.0
[/CIF]
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The compound described by MgCe3 is beta-derived structured and crystallizes in the orthorhombic Pmm2 space group. Mg(1) is bonded to two equivalent Mg(1), two equivalent Ce(1), four equivalent Ce(2), and four equivalent Ce(3) atoms to form MgCe10Mg2 cuboctahedra that share corners with eight equivalent Ce(3)Ce8Mg4 cuboctahedra, corners with ten equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with two equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(3)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(3)Ce8Mg4 cuboctahedra, and faces with eight equivalent Ce(1)Ce10Mg2 cuboctahedra. There are three inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to two equivalent Mg(1), two equivalent Ce(1), four equivalent Ce(2), and four equivalent Ce(3) atoms to form CeCe10Mg2 cuboctahedra that share corners with eight equivalent Ce(2)Ce8Mg4 cuboctahedra, corners with ten equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with two equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with four equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(3)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(3)Ce8Mg4 cuboctahedra, and faces with eight equivalent Mg(1)Ce10Mg2 cuboctahedra. In the second Ce site, Ce(2) is bonded to four equivalent Mg(1), two equivalent Ce(2), two equivalent Ce(3), and four equivalent Ce(1) atoms to form CeCe8Mg4 cuboctahedra that share corners with eight equivalent Ce(1)Ce10Mg2 cuboctahedra, corners with ten equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with two equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with four equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(3)Ce8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, and faces with eight equivalent Ce(3)Ce8Mg4 cuboctahedra. In the third Ce site, Ce(3) is bonded to four equivalent Mg(1), two equivalent Ce(2), two equivalent Ce(3), and four equivalent Ce(1) atoms to form CeCe8Mg4 cuboctahedra that share corners with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with ten equivalent Ce(3)Ce8Mg4 cuboctahedra, edges with two equivalent Ce(3)Ce8Mg4 cuboctahedra, edges with four equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(3)Ce8Mg4 cuboctahedra, and faces with eight equivalent Ce(2)Ce8Mg4 cuboctahedra. is represented by the CIF card [CIF]
data_Ce3Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.254
_cell_length_b   5.492
_cell_length_c   5.938
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   106.117
_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
  Ce  Ce0  1  0.000  0.000  1.000  1.0
  Ce  Ce1  1  0.500  0.000  0.490  1.0
  Ce  Ce2  1  0.500  0.500  0.846  1.0
  Mg  Mg3  1  0.000  0.500  0.331  1.0
[/CIF]
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