The structure described by Ba3La2Ti2Nb2O15 crystallizes in the trigonal P-3m1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 12-coordinate geometry to three equivalent O(2) and nine equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded to six equivalent O(2) and six equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, faces with six equivalent La(1)O12 cuboctahedra, faces with two equivalent Nb(1)O6 octahedra, and faces with six equivalent Ti(1)O6 octahedra. La(1) is bonded to three equivalent O(1), three equivalent O(3), and six equivalent O(2) atoms to form distorted LaO12 cuboctahedra that share corners with nine equivalent La(1)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Nb(1)O6 octahedra, and faces with four equivalent Ti(1)O6 octahedra. Ti(1) 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 Nb(1)O6 octahedra, faces with three equivalent Ba(2)O12 cuboctahedra, and faces with four equivalent La(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-4°. Nb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NbO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra,  a faceface with one Ba(2)O12 cuboctahedra, and faces with three equivalent La(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 4°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to three equivalent Ba(1), one La(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent La(1), one Ti(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Ba(2), two equivalent La(1), and two equivalent Ti(1) atoms. is represented by the CIF card [CIF]
data_Ba3La2Ti2Nb2O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.725
_cell_length_b   5.725
_cell_length_c   11.760
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   333.739
_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
  Ba  Ba0  1  0.667  0.333  0.576  1.0
  Ba  Ba1  1  0.333  0.667  0.424  1.0
  Ba  Ba2  1  0.000  0.000  0.000  1.0
  La  La3  1  0.667  0.333  0.213  1.0
  La  La4  1  0.333  0.667  0.787  1.0
  Ti  Ti5  1  0.667  0.333  0.903  1.0
  Ti  Ti6  1  0.333  0.667  0.097  1.0
  Nb  Nb7  1  0.000  0.000  0.305  1.0
  Nb  Nb8  1  0.000  0.000  0.695  1.0
  O  O9  1  0.343  0.172  0.379  1.0
  O  O10  1  0.828  0.657  0.379  1.0
  O  O11  1  0.828  0.172  0.379  1.0
  O  O12  1  0.657  0.828  0.621  1.0
  O  O13  1  0.172  0.343  0.621  1.0
  O  O14  1  0.172  0.828  0.621  1.0
  O  O15  1  0.338  0.169  0.809  1.0
  O  O16  1  0.831  0.662  0.809  1.0
  O  O17  1  0.831  0.169  0.809  1.0
  O  O18  1  0.662  0.831  0.191  1.0
  O  O19  1  0.169  0.338  0.191  1.0
  O  O20  1  0.169  0.831  0.191  1.0
  O  O21  1  0.500  0.000  0.000  1.0
  O  O22  1  0.500  0.500  0.000  1.0
  O  O23  1  0.000  0.500  0.000  1.0
[/CIF]
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The structure described by Ba3La2Ti2Nb2O15 crystallizes in the trigonal P-3m1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 12-coordinate geometry to three equivalent O(2) and nine equivalent O(1) atoms. In the second Ba site, Ba(2) is bonded to six equivalent O(2) and six equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with six equivalent Ba(2)O12 cuboctahedra, faces with six equivalent La(1)O12 cuboctahedra, faces with two equivalent Nb(1)O6 octahedra, and faces with six equivalent Ti(1)O6 octahedra. La(1) is bonded to three equivalent O(1), three equivalent O(3), and six equivalent O(2) atoms to form distorted LaO12 cuboctahedra that share corners with nine equivalent La(1)O12 cuboctahedra, faces with three equivalent Ba(2)O12 cuboctahedra, faces with three equivalent Nb(1)O6 octahedra, and faces with four equivalent Ti(1)O6 octahedra. Ti(1) 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 Nb(1)O6 octahedra, faces with three equivalent Ba(2)O12 cuboctahedra, and faces with four equivalent La(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-4°. Nb(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form NbO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra,  a faceface with one Ba(2)O12 cuboctahedra, and faces with three equivalent La(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 4°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to three equivalent Ba(1), one La(1), and one Nb(1) atom. In the second O site, O(2) is bonded in a 2-coordinate geometry to one Ba(1), one Ba(2), two equivalent La(1), one Ti(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Ba(2), two equivalent La(1), and two equivalent Ti(1) atoms. is represented by the CIF card [CIF]
data_Ba3La2Ti2Nb2O15
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.725
_cell_length_b   5.725
_cell_length_c   11.760
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   333.739
_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
  Ba  Ba0  1  0.667  0.333  0.576  1.0
  Ba  Ba1  1  0.333  0.667  0.424  1.0
  Ba  Ba2  1  0.000  0.000  0.000  1.0
  La  La3  1  0.667  0.333  0.213  1.0
  La  La4  1  0.333  0.667  0.787  1.0
  Ti  Ti5  1  0.667  0.333  0.903  1.0
  Ti  Ti6  1  0.333  0.667  0.097  1.0
  Nb  Nb7  1  0.000  0.000  0.305  1.0
  Nb  Nb8  1  0.000  0.000  0.695  1.0
  O  O9  1  0.343  0.172  0.379  1.0
  O  O10  1  0.828  0.657  0.379  1.0
  O  O11  1  0.828  0.172  0.379  1.0
  O  O12  1  0.657  0.828  0.621  1.0
  O  O13  1  0.172  0.343  0.621  1.0
  O  O14  1  0.172  0.828  0.621  1.0
  O  O15  1  0.338  0.169  0.809  1.0
  O  O16  1  0.831  0.662  0.809  1.0
  O  O17  1  0.831  0.169  0.809  1.0
  O  O18  1  0.662  0.831  0.191  1.0
  O  O19  1  0.169  0.338  0.191  1.0
  O  O20  1  0.169  0.831  0.191  1.0
  O  O21  1  0.500  0.000  0.000  1.0
  O  O22  1  0.500  0.500  0.000  1.0
  O  O23  1  0.000  0.500  0.000  1.0
[/CIF]
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