The material described by Mg6CeCr crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ce(1), and two equivalent Cr(1) atoms to form MgCe2Mg8Cr2 cuboctahedra that share corners with four equivalent Ce(1)Mg10Cr2 cuboctahedra, corners with four equivalent Cr(1)Ce2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Ce(1)Mg10Cr2 cuboctahedra, edges with two equivalent Cr(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, and faces with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ce(1), and two equivalent Cr(1) atoms to form distorted MgCe2Mg8Cr2 cuboctahedra that share corners with four equivalent Mg(3)Ce2Mg10 cuboctahedra, corners with four equivalent Mg(4)Mg10Cr2 cuboctahedra, corners with ten equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with two equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(4)Mg10Cr2 cuboctahedra, edges with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Ce(1)Mg10Cr2 cuboctahedra, edges with four equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Cr2 cuboctahedra, corners with six equivalent Mg(3)Ce2Mg10 cuboctahedra, corners with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(4)Mg10Cr2 cuboctahedra, edges with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Ce(1)Mg10Cr2 cuboctahedra, edges with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with six equivalent Cr(1)Ce2Mg10 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cr(1) atoms to form distorted MgMg10Cr2 cuboctahedra that share corners with four equivalent Mg(3)Ce2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg10Cr2 cuboctahedra, corners with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Cr(1)Ce2Mg10 cuboctahedra, edges with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with six equivalent Ce(1)Mg10Cr2 cuboctahedra. Ce(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cr(1) atoms to form CeMg10Cr2 cuboctahedra that share corners with four equivalent Cr(1)Ce2Mg10 cuboctahedra, corners with six equivalent Ce(1)Mg10Cr2 cuboctahedra, corners with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Cr(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Cr2 cuboctahedra. Cr(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ce(1) atoms to form CrCe2Mg10 cuboctahedra that share corners with four equivalent Ce(1)Mg10Cr2 cuboctahedra, corners with six equivalent Cr(1)Ce2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Ce(1)Mg10Cr2 cuboctahedra, edges with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cr2 cuboctahedra, edges with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with six equivalent Mg(3)Ce2Mg10 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CeMg6Cr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.611
_cell_length_b   6.611
_cell_length_c   5.175
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   123.255
_symmetry_Int_Tables_number   1
_cell_volume   189.141
_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  0.833  0.167  0.500  1.0
  Mg  Mg1  1  0.337  0.174  0.500  1.0
  Mg  Mg2  1  0.826  0.663  0.500  1.0
  Mg  Mg3  1  0.178  0.346  0.000  1.0
  Mg  Mg4  1  0.654  0.822  0.000  1.0
  Mg  Mg5  1  0.664  0.336  0.000  1.0
  Mg  Mg6  1  0.173  0.827  0.000  1.0
  Cr  Cr7  1  0.336  0.664  0.500  1.0
[/CIF]
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The material described by Mg6CeCr crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ce(1), and two equivalent Cr(1) atoms to form MgCe2Mg8Cr2 cuboctahedra that share corners with four equivalent Ce(1)Mg10Cr2 cuboctahedra, corners with four equivalent Cr(1)Ce2Mg10 cuboctahedra, corners with ten equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Ce(1)Mg10Cr2 cuboctahedra, edges with two equivalent Cr(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, and faces with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ce(1), and two equivalent Cr(1) atoms to form distorted MgCe2Mg8Cr2 cuboctahedra that share corners with four equivalent Mg(3)Ce2Mg10 cuboctahedra, corners with four equivalent Mg(4)Mg10Cr2 cuboctahedra, corners with ten equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with two equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(4)Mg10Cr2 cuboctahedra, edges with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Ce(1)Mg10Cr2 cuboctahedra, edges with four equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Mg10Cr2 cuboctahedra, corners with six equivalent Mg(3)Ce2Mg10 cuboctahedra, corners with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(4)Mg10Cr2 cuboctahedra, edges with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Ce(1)Mg10Cr2 cuboctahedra, edges with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with six equivalent Cr(1)Ce2Mg10 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cr(1) atoms to form distorted MgMg10Cr2 cuboctahedra that share corners with four equivalent Mg(3)Ce2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg10Cr2 cuboctahedra, corners with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Cr(1)Ce2Mg10 cuboctahedra, edges with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with six equivalent Ce(1)Mg10Cr2 cuboctahedra. Ce(1) is bonded to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Cr(1) atoms to form CeMg10Cr2 cuboctahedra that share corners with four equivalent Cr(1)Ce2Mg10 cuboctahedra, corners with six equivalent Ce(1)Mg10Cr2 cuboctahedra, corners with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Cr(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with six equivalent Mg(4)Mg10Cr2 cuboctahedra. Cr(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ce(1) atoms to form CrCe2Mg10 cuboctahedra that share corners with four equivalent Ce(1)Mg10Cr2 cuboctahedra, corners with six equivalent Cr(1)Ce2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with two equivalent Ce(1)Mg10Cr2 cuboctahedra, edges with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, edges with four equivalent Mg(4)Mg10Cr2 cuboctahedra, edges with eight equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, faces with two equivalent Mg(4)Mg10Cr2 cuboctahedra, faces with two equivalent Ce(1)Mg10Cr2 cuboctahedra, faces with two equivalent Cr(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(1)Ce2Mg8Cr2 cuboctahedra, faces with four equivalent Mg(2)Ce2Mg8Cr2 cuboctahedra, and faces with six equivalent Mg(3)Ce2Mg10 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CeMg6Cr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.611
_cell_length_b   6.611
_cell_length_c   5.175
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   123.255
_symmetry_Int_Tables_number   1
_cell_volume   189.141
_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  0.833  0.167  0.500  1.0
  Mg  Mg1  1  0.337  0.174  0.500  1.0
  Mg  Mg2  1  0.826  0.663  0.500  1.0
  Mg  Mg3  1  0.178  0.346  0.000  1.0
  Mg  Mg4  1  0.654  0.822  0.000  1.0
  Mg  Mg5  1  0.664  0.336  0.000  1.0
  Mg  Mg6  1  0.173  0.827  0.000  1.0
  Cr  Cr7  1  0.336  0.664  0.500  1.0
[/CIF]
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