The structure described by Mg6CeC crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 9-coordinate geometry to one Mg(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 in a 12-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ce(1) atoms. In the third Mg site, Mg(3) is bonded in a single-bond geometry to two equivalent Mg(1), two equivalent Mg(2), and one C(1) atom. In the fourth Mg site, Mg(4) is bonded in a single-bond geometry to two equivalent Mg(2), four equivalent Mg(1), and one C(1) atom. Ce(1) is bonded in a bent 150 degrees geometry to two equivalent Mg(2), four equivalent Mg(1), and two equivalent C(1) atoms. C(1) is bonded to one Mg(4), two equivalent Mg(3), and two equivalent Ce(1) atoms to form corner-sharing CCe2Mg3 trigonal bipyramids. is represented by the CIF card [CIF]
data_CeMg6C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.699
_cell_length_b   6.699
_cell_length_c   4.634
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.257
_symmetry_Int_Tables_number   1
_cell_volume   196.341
_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  0.344  0.656  0.500  1.0
  Mg  Mg1  1  0.876  0.736  0.500  1.0
  Mg  Mg2  1  0.264  0.124  0.500  1.0
  Mg  Mg3  1  0.786  0.214  0.500  1.0
  Mg  Mg4  1  0.660  0.918  0.000  1.0
  Mg  Mg5  1  0.082  0.340  0.000  1.0
  Mg  Mg6  1  0.594  0.406  0.000  1.0
  C  C7  1  0.393  0.607  0.000  1.0
[/CIF]
.
The structure described by Mg6CeC crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 9-coordinate geometry to one Mg(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 in a 12-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ce(1) atoms. In the third Mg site, Mg(3) is bonded in a single-bond geometry to two equivalent Mg(1), two equivalent Mg(2), and one C(1) atom. In the fourth Mg site, Mg(4) is bonded in a single-bond geometry to two equivalent Mg(2), four equivalent Mg(1), and one C(1) atom. Ce(1) is bonded in a bent 150 degrees geometry to two equivalent Mg(2), four equivalent Mg(1), and two equivalent C(1) atoms. C(1) is bonded to one Mg(4), two equivalent Mg(3), and two equivalent Ce(1) atoms to form corner-sharing CCe2Mg3 trigonal bipyramids. is represented by the CIF card [CIF]
data_CeMg6C
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.699
_cell_length_b   6.699
_cell_length_c   4.634
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   109.257
_symmetry_Int_Tables_number   1
_cell_volume   196.341
_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  0.344  0.656  0.500  1.0
  Mg  Mg1  1  0.876  0.736  0.500  1.0
  Mg  Mg2  1  0.264  0.124  0.500  1.0
  Mg  Mg3  1  0.786  0.214  0.500  1.0
  Mg  Mg4  1  0.660  0.918  0.000  1.0
  Mg  Mg5  1  0.082  0.340  0.000  1.0
  Mg  Mg6  1  0.594  0.406  0.000  1.0
  C  C7  1  0.393  0.607  0.000  1.0
[/CIF]
.