The material described by Mg5Ce crystallizes in the hexagonal P-62m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ce(1) atoms. In the second Mg site, Mg(2) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Ce(1) atoms to form MgCe3Mg9 cuboctahedra that share corners with nine equivalent Mg(2)Ce3Mg9 cuboctahedra, corners with nine equivalent Ce(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Ce3Mg9 cuboctahedra, faces with three equivalent Ce(1)Mg12 cuboctahedra, and faces with five equivalent Mg(2)Ce3Mg9 cuboctahedra. Ce(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form CeMg12 cuboctahedra that share corners with eighteen equivalent Mg(2)Ce3Mg9 cuboctahedra, edges with six equivalent Ce(1)Mg12 cuboctahedra, faces with two equivalent Ce(1)Mg12 cuboctahedra, and faces with six equivalent Mg(2)Ce3Mg9 cuboctahedra. is represented by the CIF file [CIF]
data_CeMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.798
_cell_length_b   5.798
_cell_length_c   5.352
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   155.842
_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  0.500  1.0
  Mg  Mg1  1  0.648  0.000  0.000  1.0
  Mg  Mg2  1  0.352  0.352  0.000  1.0
  Mg  Mg3  1  0.000  0.648  0.000  1.0
  Mg  Mg4  1  0.667  0.333  0.500  1.0
  Mg  Mg5  1  0.333  0.667  0.500  1.0
[/CIF]
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The material described by Mg5Ce crystallizes in the hexagonal P-62m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ce(1) atoms. In the second Mg site, Mg(2) is bonded to three equivalent Mg(2), six equivalent Mg(1), and three equivalent Ce(1) atoms to form MgCe3Mg9 cuboctahedra that share corners with nine equivalent Mg(2)Ce3Mg9 cuboctahedra, corners with nine equivalent Ce(1)Mg12 cuboctahedra, edges with six equivalent Mg(2)Ce3Mg9 cuboctahedra, faces with three equivalent Ce(1)Mg12 cuboctahedra, and faces with five equivalent Mg(2)Ce3Mg9 cuboctahedra. Ce(1) is bonded to six equivalent Mg(1) and six equivalent Mg(2) atoms to form CeMg12 cuboctahedra that share corners with eighteen equivalent Mg(2)Ce3Mg9 cuboctahedra, edges with six equivalent Ce(1)Mg12 cuboctahedra, faces with two equivalent Ce(1)Mg12 cuboctahedra, and faces with six equivalent Mg(2)Ce3Mg9 cuboctahedra. is represented by the CIF file [CIF]
data_CeMg5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.798
_cell_length_b   5.798
_cell_length_c   5.352
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   155.842
_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  0.500  1.0
  Mg  Mg1  1  0.648  0.000  0.000  1.0
  Mg  Mg2  1  0.352  0.352  0.000  1.0
  Mg  Mg3  1  0.000  0.648  0.000  1.0
  Mg  Mg4  1  0.667  0.333  0.500  1.0
  Mg  Mg5  1  0.333  0.667  0.500  1.0
[/CIF]
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