The material described by CeSiO2N crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to six equivalent N(1) and six equivalent O(1) atoms to form distorted CeN6O6 cuboctahedra that share edges with six equivalent Ce(2)O6 octahedra, faces with two equivalent Ce(1)N6O6 cuboctahedra, and faces with six equivalent Si(1)N2O2 tetrahedra. In the second Ce site, Ce(2) is bonded to six equivalent O(1) atoms to form distorted CeO6 octahedra that share corners with six equivalent Si(1)N2O2 tetrahedra, edges with three equivalent Ce(1)N6O6 cuboctahedra, and edges with three equivalent Ce(2)O6 octahedra. Si(1) is bonded to two equivalent N(1) and two equivalent O(1) atoms to form SiN2O2 tetrahedra that share corners with four equivalent Ce(2)O6 octahedra, corners with two equivalent Si(1)N2O2 tetrahedra, and faces with two equivalent Ce(1)N6O6 cuboctahedra. The corner-sharing octahedral tilt angles are 57°. N(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Ce(1) and two equivalent Si(1) atoms. O(1) is bonded in a 4-coordinate geometry to one Ce(1), two equivalent Ce(2), and one Si(1) atom. is represented by the CIF file [CIF]
data_CeSiNO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.077
_cell_length_b   7.077
_cell_length_c   9.732
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   422.137
_cell_formula_units_Z   6
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  0.000  1.0
  Ce  Ce1  1  0.333  0.667  0.500  1.0
  Ce  Ce2  1  0.667  0.333  0.000  1.0
  Ce  Ce3  1  0.667  0.333  0.500  1.0
  Ce  Ce4  1  0.333  0.667  0.000  1.0
  Ce  Ce5  1  0.000  0.000  0.500  1.0
  Si  Si6  1  0.751  0.000  0.250  1.0
  Si  Si7  1  0.249  0.249  0.250  1.0
  Si  Si8  1  0.751  0.751  0.750  1.0
  Si  Si9  1  0.000  0.751  0.250  1.0
  Si  Si10  1  0.249  0.000  0.750  1.0
  Si  Si11  1  0.000  0.249  0.750  1.0
  N  N12  1  0.000  0.229  0.250  1.0
  N  N13  1  0.229  0.000  0.250  1.0
  N  N14  1  0.771  0.771  0.250  1.0
  N  N15  1  0.000  0.771  0.750  1.0
  N  N16  1  0.771  0.000  0.750  1.0
  N  N17  1  0.229  0.229  0.750  1.0
  O  O18  1  0.369  0.000  0.602  1.0
  O  O19  1  0.000  0.631  0.102  1.0
  O  O20  1  0.631  0.631  0.602  1.0
  O  O21  1  0.000  0.369  0.602  1.0
  O  O22  1  0.000  0.631  0.398  1.0
  O  O23  1  0.369  0.369  0.398  1.0
  O  O24  1  0.000  0.369  0.898  1.0
  O  O25  1  0.369  0.369  0.102  1.0
  O  O26  1  0.631  0.631  0.898  1.0
  O  O27  1  0.631  0.000  0.102  1.0
  O  O28  1  0.369  0.000  0.898  1.0
  O  O29  1  0.631  0.000  0.398  1.0
[/CIF]
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The material described by CeSiO2N crystallizes in the hexagonal P6_3/mcm space group. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to six equivalent N(1) and six equivalent O(1) atoms to form distorted CeN6O6 cuboctahedra that share edges with six equivalent Ce(2)O6 octahedra, faces with two equivalent Ce(1)N6O6 cuboctahedra, and faces with six equivalent Si(1)N2O2 tetrahedra. In the second Ce site, Ce(2) is bonded to six equivalent O(1) atoms to form distorted CeO6 octahedra that share corners with six equivalent Si(1)N2O2 tetrahedra, edges with three equivalent Ce(1)N6O6 cuboctahedra, and edges with three equivalent Ce(2)O6 octahedra. Si(1) is bonded to two equivalent N(1) and two equivalent O(1) atoms to form SiN2O2 tetrahedra that share corners with four equivalent Ce(2)O6 octahedra, corners with two equivalent Si(1)N2O2 tetrahedra, and faces with two equivalent Ce(1)N6O6 cuboctahedra. The corner-sharing octahedral tilt angles are 57°. N(1) is bonded in a distorted bent 120 degrees geometry to two equivalent Ce(1) and two equivalent Si(1) atoms. O(1) is bonded in a 4-coordinate geometry to one Ce(1), two equivalent Ce(2), and one Si(1) atom. is represented by the CIF file [CIF]
data_CeSiNO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.077
_cell_length_b   7.077
_cell_length_c   9.732
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   422.137
_cell_formula_units_Z   6
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  0.000  1.0
  Ce  Ce1  1  0.333  0.667  0.500  1.0
  Ce  Ce2  1  0.667  0.333  0.000  1.0
  Ce  Ce3  1  0.667  0.333  0.500  1.0
  Ce  Ce4  1  0.333  0.667  0.000  1.0
  Ce  Ce5  1  0.000  0.000  0.500  1.0
  Si  Si6  1  0.751  0.000  0.250  1.0
  Si  Si7  1  0.249  0.249  0.250  1.0
  Si  Si8  1  0.751  0.751  0.750  1.0
  Si  Si9  1  0.000  0.751  0.250  1.0
  Si  Si10  1  0.249  0.000  0.750  1.0
  Si  Si11  1  0.000  0.249  0.750  1.0
  N  N12  1  0.000  0.229  0.250  1.0
  N  N13  1  0.229  0.000  0.250  1.0
  N  N14  1  0.771  0.771  0.250  1.0
  N  N15  1  0.000  0.771  0.750  1.0
  N  N16  1  0.771  0.000  0.750  1.0
  N  N17  1  0.229  0.229  0.750  1.0
  O  O18  1  0.369  0.000  0.602  1.0
  O  O19  1  0.000  0.631  0.102  1.0
  O  O20  1  0.631  0.631  0.602  1.0
  O  O21  1  0.000  0.369  0.602  1.0
  O  O22  1  0.000  0.631  0.398  1.0
  O  O23  1  0.369  0.369  0.398  1.0
  O  O24  1  0.000  0.369  0.898  1.0
  O  O25  1  0.369  0.369  0.102  1.0
  O  O26  1  0.631  0.631  0.898  1.0
  O  O27  1  0.631  0.000  0.102  1.0
  O  O28  1  0.369  0.000  0.898  1.0
  O  O29  1  0.631  0.000  0.398  1.0
[/CIF]
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