The structure described by Ba2CaTb2Ti3(CuO7)2 crystallizes in the tetragonal P4mm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent O(1), four equivalent O(3), and four equivalent O(5) atoms to form distorted BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ti(1)O6 octahedra, and faces with four equivalent Cu(1)O5 square pyramids. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to four equivalent O(2), four equivalent O(4), and four equivalent O(6) atoms. Ca(1) is bonded in a 12-coordinate geometry to four equivalent O(1), four equivalent O(7), and four equivalent O(9) atoms. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a body-centered cubic geometry to four equivalent O(3) and four equivalent O(4) atoms. In the second Tb site, Tb(2) is bonded to four equivalent O(2), four equivalent O(8), and four equivalent O(9) atoms to form TbO12 cuboctahedra that share corners with four equivalent Tb(2)O12 cuboctahedra, faces with four equivalent Tb(2)O12 cuboctahedra, faces with four equivalent Ti(2)O6 octahedra, and faces with four equivalent Ti(3)O6 octahedra. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(5), one O(7), and four equivalent O(1) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(3)O6 octahedra, corners with four equivalent Ti(1)O6 octahedra,  a cornercorner with one Cu(1)O5 square pyramid, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-12°. In the second Ti site, Ti(2) is bonded to one O(6), one O(8), and four equivalent O(2) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(3)O6 octahedra, corners with four equivalent Ti(2)O6 octahedra,  a cornercorner with one Cu(2)O5 square pyramid, and faces with four equivalent Tb(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the third Ti site, Ti(3) is bonded to one O(7), one O(8), and four equivalent O(9) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra, corners with four equivalent Ti(3)O6 octahedra, and faces with four equivalent Tb(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-12°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(5) and four equivalent O(3) atoms to form CuO5 square pyramids that share  a cornercorner with one Ti(1)O6 octahedra, corners with four equivalent Cu(1)O5 square pyramids, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Cu site, Cu(2) is bonded to one O(6) and four equivalent O(4) atoms to form distorted CuO5 square pyramids that share  a cornercorner with one Ti(2)O6 octahedra and corners with four equivalent Cu(2)O5 square pyramids. The corner-sharing octahedra are not tilted. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Ca(1), and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(2), two equivalent Tb(2), and two equivalent Ti(2) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Cu(1) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Tb(1), and two equivalent Cu(2) atoms. In the fifth O site, O(5) is bonded to four equivalent Ba(1), one Ti(1), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing OBa4TiCu octahedra. The corner-sharing octahedral tilt angles are 15°. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to four equivalent Ba(2), one Ti(2), and one Cu(2) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to four equivalent Ca(1), one Ti(1), and one Ti(3) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to four equivalent Tb(2), one Ti(2), and one Ti(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to two equivalent Ca(1), two equivalent Tb(2), and two equivalent Ti(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2CaTb2Ti3(CuO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.905
_cell_length_b   3.905
_cell_length_c   19.879
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   303.189
_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  0.500  0.500  0.813  1.0
  Ba  Ba1  1  0.500  0.500  0.184  1.0
  Ca  Ca2  1  0.500  0.500  0.611  1.0
  Tb  Tb3  1  0.500  0.500  0.999  1.0
  Tb  Tb4  1  0.500  0.500  0.401  1.0
  Ti  Ti5  1  0.000  0.000  0.701  1.0
  Ti  Ti6  1  0.000  0.000  0.301  1.0
  Ti  Ti7  1  0.000  0.000  0.501  1.0
  Cu  Cu8  1  0.000  0.000  0.918  1.0
  Cu  Cu9  1  0.000  0.000  0.081  1.0
  O  O10  1  0.000  0.500  0.691  1.0
  O  O11  1  0.500  0.000  0.313  1.0
  O  O12  1  0.000  0.500  0.313  1.0
  O  O13  1  0.500  0.000  0.691  1.0
  O  O14  1  0.000  0.500  0.927  1.0
  O  O15  1  0.500  0.000  0.073  1.0
  O  O16  1  0.000  0.500  0.073  1.0
  O  O17  1  0.500  0.000  0.927  1.0
  O  O18  1  0.000  0.000  0.795  1.0
  O  O19  1  0.000  0.000  0.207  1.0
  O  O20  1  0.000  0.000  0.595  1.0
  O  O21  1  0.000  0.000  0.402  1.0
  O  O22  1  0.000  0.500  0.490  1.0
  O  O23  1  0.500  0.000  0.490  1.0
[/CIF]
.
The structure described by Ba2CaTb2Ti3(CuO7)2 crystallizes in the tetragonal P4mm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to four equivalent O(1), four equivalent O(3), and four equivalent O(5) atoms to form distorted BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ti(1)O6 octahedra, and faces with four equivalent Cu(1)O5 square pyramids. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to four equivalent O(2), four equivalent O(4), and four equivalent O(6) atoms. Ca(1) is bonded in a 12-coordinate geometry to four equivalent O(1), four equivalent O(7), and four equivalent O(9) atoms. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a body-centered cubic geometry to four equivalent O(3) and four equivalent O(4) atoms. In the second Tb site, Tb(2) is bonded to four equivalent O(2), four equivalent O(8), and four equivalent O(9) atoms to form TbO12 cuboctahedra that share corners with four equivalent Tb(2)O12 cuboctahedra, faces with four equivalent Tb(2)O12 cuboctahedra, faces with four equivalent Ti(2)O6 octahedra, and faces with four equivalent Ti(3)O6 octahedra. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(5), one O(7), and four equivalent O(1) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(3)O6 octahedra, corners with four equivalent Ti(1)O6 octahedra,  a cornercorner with one Cu(1)O5 square pyramid, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-12°. In the second Ti site, Ti(2) is bonded to one O(6), one O(8), and four equivalent O(2) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(3)O6 octahedra, corners with four equivalent Ti(2)O6 octahedra,  a cornercorner with one Cu(2)O5 square pyramid, and faces with four equivalent Tb(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-14°. In the third Ti site, Ti(3) is bonded to one O(7), one O(8), and four equivalent O(9) atoms to form TiO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra, corners with four equivalent Ti(3)O6 octahedra, and faces with four equivalent Tb(2)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-12°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(5) and four equivalent O(3) atoms to form CuO5 square pyramids that share  a cornercorner with one Ti(1)O6 octahedra, corners with four equivalent Cu(1)O5 square pyramids, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Cu site, Cu(2) is bonded to one O(6) and four equivalent O(4) atoms to form distorted CuO5 square pyramids that share  a cornercorner with one Ti(2)O6 octahedra and corners with four equivalent Cu(2)O5 square pyramids. The corner-sharing octahedra are not tilted. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Ca(1), and two equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a 2-coordinate geometry to two equivalent Ba(2), two equivalent Tb(2), and two equivalent Ti(2) atoms. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Tb(1), and two equivalent Cu(1) atoms. In the fourth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ba(2), two equivalent Tb(1), and two equivalent Cu(2) atoms. In the fifth O site, O(5) is bonded to four equivalent Ba(1), one Ti(1), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing OBa4TiCu octahedra. The corner-sharing octahedral tilt angles are 15°. In the sixth O site, O(6) is bonded in a 6-coordinate geometry to four equivalent Ba(2), one Ti(2), and one Cu(2) atom. In the seventh O site, O(7) is bonded in a distorted linear geometry to four equivalent Ca(1), one Ti(1), and one Ti(3) atom. In the eighth O site, O(8) is bonded in a distorted linear geometry to four equivalent Tb(2), one Ti(2), and one Ti(3) atom. In the ninth O site, O(9) is bonded in a 2-coordinate geometry to two equivalent Ca(1), two equivalent Tb(2), and two equivalent Ti(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2CaTb2Ti3(CuO7)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.905
_cell_length_b   3.905
_cell_length_c   19.879
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   303.189
_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  0.500  0.500  0.813  1.0
  Ba  Ba1  1  0.500  0.500  0.184  1.0
  Ca  Ca2  1  0.500  0.500  0.611  1.0
  Tb  Tb3  1  0.500  0.500  0.999  1.0
  Tb  Tb4  1  0.500  0.500  0.401  1.0
  Ti  Ti5  1  0.000  0.000  0.701  1.0
  Ti  Ti6  1  0.000  0.000  0.301  1.0
  Ti  Ti7  1  0.000  0.000  0.501  1.0
  Cu  Cu8  1  0.000  0.000  0.918  1.0
  Cu  Cu9  1  0.000  0.000  0.081  1.0
  O  O10  1  0.000  0.500  0.691  1.0
  O  O11  1  0.500  0.000  0.313  1.0
  O  O12  1  0.000  0.500  0.313  1.0
  O  O13  1  0.500  0.000  0.691  1.0
  O  O14  1  0.000  0.500  0.927  1.0
  O  O15  1  0.500  0.000  0.073  1.0
  O  O16  1  0.000  0.500  0.073  1.0
  O  O17  1  0.500  0.000  0.927  1.0
  O  O18  1  0.000  0.000  0.795  1.0
  O  O19  1  0.000  0.000  0.207  1.0
  O  O20  1  0.000  0.000  0.595  1.0
  O  O21  1  0.000  0.000  0.402  1.0
  O  O22  1  0.000  0.500  0.490  1.0
  O  O23  1  0.500  0.000  0.490  1.0
[/CIF]
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