The crystal structure described by KMg6Ce crystallizes in the orthorhombic Amm2 space group. K(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ce(1) atoms to form KCe2Mg10 cuboctahedra that share corners with four equivalent Mg(2)K2Mg10 cuboctahedra, corners with six equivalent K(1)Ce2Mg10 cuboctahedra, edges with two equivalent Mg(2)K2Mg10 cuboctahedra, edges with four equivalent Ce(1)K2Mg10 cuboctahedra, faces with two equivalent K(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(2)K2Mg10 cuboctahedra, faces with two equivalent Ce(1)K2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Ce2Mg10 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to two equivalent K(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Ce(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent K(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form distorted MgK2Mg10 cuboctahedra that share corners with four equivalent K(1)Ce2Mg10 cuboctahedra, corners with six equivalent Mg(2)K2Mg10 cuboctahedra, edges with two equivalent K(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(4)Ce2Mg10 cuboctahedra, faces with two equivalent K(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(2)K2Mg10 cuboctahedra, and faces with six equivalent Ce(1)K2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to two equivalent K(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent Ce(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with four equivalent Ce(1)K2Mg10 cuboctahedra, corners with six equivalent Mg(4)Ce2Mg10 cuboctahedra, edges with two equivalent Ce(1)K2Mg10 cuboctahedra, edges with four equivalent Mg(2)K2Mg10 cuboctahedra, faces with two equivalent Mg(4)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(2)K2Mg10 cuboctahedra, faces with two equivalent Ce(1)K2Mg10 cuboctahedra, and faces with six equivalent K(1)Ce2Mg10 cuboctahedra. Ce(1) is bonded to two equivalent K(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form CeK2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Ce2Mg10 cuboctahedra, corners with six equivalent Ce(1)K2Mg10 cuboctahedra, edges with two equivalent Mg(4)Ce2Mg10 cuboctahedra, edges with four equivalent K(1)Ce2Mg10 cuboctahedra, faces with two equivalent K(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Ce2Mg10 cuboctahedra, faces with two equivalent Ce(1)K2Mg10 cuboctahedra, and faces with six equivalent Mg(2)K2Mg10 cuboctahedra. is represented by the CIF file [CIF]
data_KCeMg6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.405
_cell_length_b   6.922
_cell_length_c   6.922
_cell_angle_alpha   119.015
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   226.476
_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  0.500  0.345  0.655  1.0
  K  K1  1  0.000  0.151  0.849  1.0
  Mg  Mg2  1  1.000  0.660  0.835  1.0
  Mg  Mg3  1  1.000  0.165  0.340  1.0
  Mg  Mg4  1  0.000  0.667  0.333  1.0
  Mg  Mg5  1  0.500  0.817  0.648  1.0
  Mg  Mg6  1  0.500  0.352  0.183  1.0
  Mg  Mg7  1  0.500  0.845  0.155  1.0
[/CIF]
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The crystal structure described by KMg6Ce crystallizes in the orthorhombic Amm2 space group. K(1) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ce(1) atoms to form KCe2Mg10 cuboctahedra that share corners with four equivalent Mg(2)K2Mg10 cuboctahedra, corners with six equivalent K(1)Ce2Mg10 cuboctahedra, edges with two equivalent Mg(2)K2Mg10 cuboctahedra, edges with four equivalent Ce(1)K2Mg10 cuboctahedra, faces with two equivalent K(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(2)K2Mg10 cuboctahedra, faces with two equivalent Ce(1)K2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Ce2Mg10 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 4-coordinate geometry to two equivalent K(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Ce(1) atoms. In the second Mg site, Mg(2) is bonded to two equivalent K(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form distorted MgK2Mg10 cuboctahedra that share corners with four equivalent K(1)Ce2Mg10 cuboctahedra, corners with six equivalent Mg(2)K2Mg10 cuboctahedra, edges with two equivalent K(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(4)Ce2Mg10 cuboctahedra, faces with two equivalent K(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(2)K2Mg10 cuboctahedra, and faces with six equivalent Ce(1)K2Mg10 cuboctahedra. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to two equivalent K(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent Ce(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(2), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with four equivalent Ce(1)K2Mg10 cuboctahedra, corners with six equivalent Mg(4)Ce2Mg10 cuboctahedra, edges with two equivalent Ce(1)K2Mg10 cuboctahedra, edges with four equivalent Mg(2)K2Mg10 cuboctahedra, faces with two equivalent Mg(4)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(2)K2Mg10 cuboctahedra, faces with two equivalent Ce(1)K2Mg10 cuboctahedra, and faces with six equivalent K(1)Ce2Mg10 cuboctahedra. Ce(1) is bonded to two equivalent K(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form CeK2Mg10 cuboctahedra that share corners with four equivalent Mg(4)Ce2Mg10 cuboctahedra, corners with six equivalent Ce(1)K2Mg10 cuboctahedra, edges with two equivalent Mg(4)Ce2Mg10 cuboctahedra, edges with four equivalent K(1)Ce2Mg10 cuboctahedra, faces with two equivalent K(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Ce2Mg10 cuboctahedra, faces with two equivalent Ce(1)K2Mg10 cuboctahedra, and faces with six equivalent Mg(2)K2Mg10 cuboctahedra. is represented by the CIF file [CIF]
data_KCeMg6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.405
_cell_length_b   6.922
_cell_length_c   6.922
_cell_angle_alpha   119.015
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   226.476
_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  0.500  0.345  0.655  1.0
  K  K1  1  0.000  0.151  0.849  1.0
  Mg  Mg2  1  1.000  0.660  0.835  1.0
  Mg  Mg3  1  1.000  0.165  0.340  1.0
  Mg  Mg4  1  0.000  0.667  0.333  1.0
  Mg  Mg5  1  0.500  0.817  0.648  1.0
  Mg  Mg6  1  0.500  0.352  0.183  1.0
  Mg  Mg7  1  0.500  0.845  0.155  1.0
[/CIF]
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