The crystal structure described by Sr2Ce2Ti5O15 crystallizes in the trigonal R-3m space group. Sr(1) is bonded to three equivalent O(2) and nine equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with three equivalent Ce(1)O12 cuboctahedra, corners with six equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Ce(1)O12 cuboctahedra,  a faceface with one Ti(2)O6 octahedra, faces with three equivalent Ti(3)O6 octahedra, and faces with four equivalent Ti(1)O6 octahedra. Ce(1) is bonded to three equivalent O(1), three equivalent O(3), and six equivalent O(2) atoms to form CeO12 cuboctahedra that share corners with three equivalent Sr(1)O12 cuboctahedra, corners with nine equivalent Ce(1)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra,  a faceface with one Ti(3)O6 octahedra, faces with three equivalent Ti(1)O6 octahedra, and faces with four equivalent Ti(2)O6 octahedra. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form TiO6 octahedra that share corners with three equivalent Ti(2)O6 octahedra, corners with three equivalent Ti(3)O6 octahedra, faces with three equivalent Ce(1)O12 cuboctahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 1-7°. In the second Ti site, Ti(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra,  a faceface with one Sr(1)O12 cuboctahedra, and faces with four equivalent Ce(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the third Ti site, Ti(3) is bonded to six equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra, faces with two equivalent Ce(1)O12 cuboctahedra, and faces with six equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 1°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to three equivalent Sr(1), one Ce(1), one Ti(1), and one Ti(3) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Sr(1), two equivalent Ce(1), one Ti(1), and one Ti(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Ce(1) and two equivalent Ti(2) atoms. is represented by the CIF card [CIF]
data_Sr2Ce2Ti5O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.714
_cell_length_b   11.714
_cell_length_c   11.714
_cell_angle_alpha   27.299
_cell_angle_beta   27.299
_cell_angle_gamma   27.299
_symmetry_Int_Tables_number   1
_cell_volume   298.347
_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
  Sr  Sr0  1  0.200  0.200  0.200  1.0
  Sr  Sr1  1  0.800  0.800  0.800  1.0
  Ce  Ce2  1  0.602  0.602  0.602  1.0
  Ce  Ce3  1  0.398  0.398  0.398  1.0
  Ti  Ti4  1  0.903  0.903  0.903  1.0
  Ti  Ti5  1  0.698  0.698  0.698  1.0
  Ti  Ti6  1  0.302  0.302  0.302  1.0
  Ti  Ti7  1  0.097  0.097  0.097  1.0
  Ti  Ti8  1  0.500  0.500  0.500  1.0
  O  O9  1  0.301  0.793  0.301  1.0
  O  O10  1  0.103  0.590  0.103  1.0
  O  O11  1  0.699  0.207  0.699  1.0
  O  O12  1  0.500  0.000  0.500  1.0
  O  O13  1  0.897  0.410  0.897  1.0
  O  O14  1  0.699  0.699  0.207  1.0
  O  O15  1  0.500  0.500  0.000  1.0
  O  O16  1  0.103  0.103  0.590  1.0
  O  O17  1  0.897  0.897  0.410  1.0
  O  O18  1  0.301  0.301  0.793  1.0
  O  O19  1  0.590  0.103  0.103  1.0
  O  O20  1  0.410  0.897  0.897  1.0
  O  O21  1  0.000  0.500  0.500  1.0
  O  O22  1  0.793  0.301  0.301  1.0
  O  O23  1  0.207  0.699  0.699  1.0
[/CIF]
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The crystal structure described by Sr2Ce2Ti5O15 crystallizes in the trigonal R-3m space group. Sr(1) is bonded to three equivalent O(2) and nine equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with three equivalent Ce(1)O12 cuboctahedra, corners with six equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra, faces with three equivalent Ce(1)O12 cuboctahedra,  a faceface with one Ti(2)O6 octahedra, faces with three equivalent Ti(3)O6 octahedra, and faces with four equivalent Ti(1)O6 octahedra. Ce(1) is bonded to three equivalent O(1), three equivalent O(3), and six equivalent O(2) atoms to form CeO12 cuboctahedra that share corners with three equivalent Sr(1)O12 cuboctahedra, corners with nine equivalent Ce(1)O12 cuboctahedra, faces with three equivalent Sr(1)O12 cuboctahedra,  a faceface with one Ti(3)O6 octahedra, faces with three equivalent Ti(1)O6 octahedra, and faces with four equivalent Ti(2)O6 octahedra. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form TiO6 octahedra that share corners with three equivalent Ti(2)O6 octahedra, corners with three equivalent Ti(3)O6 octahedra, faces with three equivalent Ce(1)O12 cuboctahedra, and faces with four equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 1-7°. In the second Ti site, Ti(2) is bonded to three equivalent O(2) and three equivalent O(3) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, corners with three equivalent Ti(2)O6 octahedra,  a faceface with one Sr(1)O12 cuboctahedra, and faces with four equivalent Ce(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the third Ti site, Ti(3) is bonded to six equivalent O(1) atoms to form TiO6 octahedra that share corners with six equivalent Ti(1)O6 octahedra, faces with two equivalent Ce(1)O12 cuboctahedra, and faces with six equivalent Sr(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 1°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to three equivalent Sr(1), one Ce(1), one Ti(1), and one Ti(3) atom. In the second O site, O(2) is bonded in a distorted linear geometry to one Sr(1), two equivalent Ce(1), one Ti(1), and one Ti(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Ce(1) and two equivalent Ti(2) atoms. is represented by the CIF card [CIF]
data_Sr2Ce2Ti5O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.714
_cell_length_b   11.714
_cell_length_c   11.714
_cell_angle_alpha   27.299
_cell_angle_beta   27.299
_cell_angle_gamma   27.299
_symmetry_Int_Tables_number   1
_cell_volume   298.347
_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
  Sr  Sr0  1  0.200  0.200  0.200  1.0
  Sr  Sr1  1  0.800  0.800  0.800  1.0
  Ce  Ce2  1  0.602  0.602  0.602  1.0
  Ce  Ce3  1  0.398  0.398  0.398  1.0
  Ti  Ti4  1  0.903  0.903  0.903  1.0
  Ti  Ti5  1  0.698  0.698  0.698  1.0
  Ti  Ti6  1  0.302  0.302  0.302  1.0
  Ti  Ti7  1  0.097  0.097  0.097  1.0
  Ti  Ti8  1  0.500  0.500  0.500  1.0
  O  O9  1  0.301  0.793  0.301  1.0
  O  O10  1  0.103  0.590  0.103  1.0
  O  O11  1  0.699  0.207  0.699  1.0
  O  O12  1  0.500  0.000  0.500  1.0
  O  O13  1  0.897  0.410  0.897  1.0
  O  O14  1  0.699  0.699  0.207  1.0
  O  O15  1  0.500  0.500  0.000  1.0
  O  O16  1  0.103  0.103  0.590  1.0
  O  O17  1  0.897  0.897  0.410  1.0
  O  O18  1  0.301  0.301  0.793  1.0
  O  O19  1  0.590  0.103  0.103  1.0
  O  O20  1  0.410  0.897  0.897  1.0
  O  O21  1  0.000  0.500  0.500  1.0
  O  O22  1  0.793  0.301  0.301  1.0
  O  O23  1  0.207  0.699  0.699  1.0
[/CIF]
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