The structure described by MgCe5 is beta-derived structured and crystallizes in the monoclinic Cm space group. Mg(1) is bonded to two equivalent Mg(1), one Ce(4), two equivalent Ce(1), two equivalent Ce(3), two equivalent Ce(5), and three equivalent Ce(2) atoms to form MgCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with two equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with three equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(4)Ce11Mg cuboctahedra, edges with six equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with two equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(4)Ce11Mg cuboctahedra, and faces with five equivalent Ce(2)Ce9Mg3 cuboctahedra. There are five inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to two equivalent Mg(1), one Ce(3), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(4), and three equivalent Ce(5) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Ce(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce11Mg cuboctahedra, corners with six equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with two equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(4)Ce11Mg cuboctahedra, edges with three equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with four equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with six equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with three equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(4)Ce11Mg cuboctahedra, faces with three equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with four equivalent Ce(3)Ce10Mg2 cuboctahedra, and faces with five equivalent Ce(5)Ce10Mg2 cuboctahedra. In the second Ce site, Ce(2) is bonded to three equivalent Mg(1), one Ce(5), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(3), and two equivalent Ce(4) atoms to form distorted CeCe9Mg3 cuboctahedra that share corners with six equivalent Ce(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce11Mg cuboctahedra, corners with six equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with two equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(4)Ce11Mg cuboctahedra, edges with four equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with six equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with three equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(4)Ce11Mg cuboctahedra, faces with four equivalent Ce(5)Ce10Mg2 cuboctahedra, and faces with five equivalent Mg(1)Ce10Mg2 cuboctahedra. In the third Ce site, Ce(3) is bonded to two equivalent Mg(1), one Ce(1), two equivalent Ce(2), two equivalent Ce(3), two equivalent Ce(5), and three equivalent Ce(4) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with two equivalent Ce(4)Ce11Mg cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with six equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with two equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with three equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with four equivalent Ce(1)Ce10Mg2 cuboctahedra, and faces with five equivalent Ce(4)Ce11Mg cuboctahedra. In the fourth Ce site, Ce(4) is bonded to one Mg(1), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(4), two equivalent Ce(5), and three equivalent Ce(3) atoms to form distorted CeCe11Mg cuboctahedra that share corners with six equivalent Ce(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce11Mg cuboctahedra, corners with six equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with two equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with four equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with six equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(4)Ce11Mg cuboctahedra, faces with three equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, and faces with five equivalent Ce(3)Ce10Mg2 cuboctahedra. In the fifth Ce site, Ce(5) is bonded to two equivalent Mg(1), one Ce(2), two equivalent Ce(3), two equivalent Ce(4), two equivalent Ce(5), and three equivalent Ce(1) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with two equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with six equivalent Ce(4)Ce11Mg cuboctahedra, faces with two equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with three equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(4)Ce11Mg cuboctahedra, faces with four equivalent Ce(2)Ce9Mg3 cuboctahedra, and faces with five equivalent Ce(1)Ce10Mg2 cuboctahedra. is represented by the CIF card [CIF]
data_Ce5Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.574
_cell_length_b   6.574
_cell_length_c   8.017
_cell_angle_alpha   71.163
_cell_angle_beta   71.163
_cell_angle_gamma   28.536
_symmetry_Int_Tables_number   1
_cell_volume   156.067
_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  0.001  0.001  0.017  1.0
  Ce  Ce1  1  0.333  0.333  0.330  1.0
  Ce  Ce2  1  0.938  0.938  0.625  1.0
  Ce  Ce3  1  0.651  0.651  0.676  1.0
  Ce  Ce4  1  0.295  0.295  0.908  1.0
  Mg  Mg5  1  0.614  0.614  0.277  1.0
[/CIF]
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The structure described by MgCe5 is beta-derived structured and crystallizes in the monoclinic Cm space group. Mg(1) is bonded to two equivalent Mg(1), one Ce(4), two equivalent Ce(1), two equivalent Ce(3), two equivalent Ce(5), and three equivalent Ce(2) atoms to form MgCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with two equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with three equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(4)Ce11Mg cuboctahedra, edges with six equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with two equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(4)Ce11Mg cuboctahedra, and faces with five equivalent Ce(2)Ce9Mg3 cuboctahedra. There are five inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to two equivalent Mg(1), one Ce(3), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(4), and three equivalent Ce(5) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Ce(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce11Mg cuboctahedra, corners with six equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with two equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(4)Ce11Mg cuboctahedra, edges with three equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with four equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with six equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with three equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(4)Ce11Mg cuboctahedra, faces with three equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with four equivalent Ce(3)Ce10Mg2 cuboctahedra, and faces with five equivalent Ce(5)Ce10Mg2 cuboctahedra. In the second Ce site, Ce(2) is bonded to three equivalent Mg(1), one Ce(5), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(3), and two equivalent Ce(4) atoms to form distorted CeCe9Mg3 cuboctahedra that share corners with six equivalent Ce(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce11Mg cuboctahedra, corners with six equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with two equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(4)Ce11Mg cuboctahedra, edges with four equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with six equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with three equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(4)Ce11Mg cuboctahedra, faces with four equivalent Ce(5)Ce10Mg2 cuboctahedra, and faces with five equivalent Mg(1)Ce10Mg2 cuboctahedra. In the third Ce site, Ce(3) is bonded to two equivalent Mg(1), one Ce(1), two equivalent Ce(2), two equivalent Ce(3), two equivalent Ce(5), and three equivalent Ce(4) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with two equivalent Ce(4)Ce11Mg cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with six equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with two equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with three equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with four equivalent Ce(1)Ce10Mg2 cuboctahedra, and faces with five equivalent Ce(4)Ce11Mg cuboctahedra. In the fourth Ce site, Ce(4) is bonded to one Mg(1), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(4), two equivalent Ce(5), and three equivalent Ce(3) atoms to form distorted CeCe11Mg cuboctahedra that share corners with six equivalent Ce(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce11Mg cuboctahedra, corners with six equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with two equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with four equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with six equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(4)Ce11Mg cuboctahedra, faces with three equivalent Ce(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(2)Ce9Mg3 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, and faces with five equivalent Ce(3)Ce10Mg2 cuboctahedra. In the fifth Ce site, Ce(5) is bonded to two equivalent Mg(1), one Ce(2), two equivalent Ce(3), two equivalent Ce(4), two equivalent Ce(5), and three equivalent Ce(1) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with two equivalent Ce(1)Ce10Mg2 cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce9Mg3 cuboctahedra, edges with six equivalent Ce(4)Ce11Mg cuboctahedra, faces with two equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with three equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with three equivalent Ce(4)Ce11Mg cuboctahedra, faces with four equivalent Ce(2)Ce9Mg3 cuboctahedra, and faces with five equivalent Ce(1)Ce10Mg2 cuboctahedra. is represented by the CIF card [CIF]
data_Ce5Mg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.574
_cell_length_b   6.574
_cell_length_c   8.017
_cell_angle_alpha   71.163
_cell_angle_beta   71.163
_cell_angle_gamma   28.536
_symmetry_Int_Tables_number   1
_cell_volume   156.067
_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  0.001  0.001  0.017  1.0
  Ce  Ce1  1  0.333  0.333  0.330  1.0
  Ce  Ce2  1  0.938  0.938  0.625  1.0
  Ce  Ce3  1  0.651  0.651  0.676  1.0
  Ce  Ce4  1  0.295  0.295  0.908  1.0
  Mg  Mg5  1  0.614  0.614  0.277  1.0
[/CIF]
.