The structure described by Cu3Ti2Ta2O12 crystallizes in the monoclinic C2/m space group. Ti(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra and corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-40°. Ta(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra and corners with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles are 40°. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to four equivalent O(4) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. In the third Cu site, Cu(3) is bonded in a square co-planar geometry to four equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Ti(1) and one Cu(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Ta(1) and one Cu(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ta(1), and one Cu(3) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ta(1), and one Cu(1) atom. is represented by the CIF card [CIF]
data_Ta2Ti2(CuO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.488
_cell_length_b   6.488
_cell_length_c   7.508
_cell_angle_alpha   54.986
_cell_angle_beta   54.986
_cell_angle_gamma   70.815
_symmetry_Int_Tables_number   1
_cell_volume   211.993
_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
  Ta  Ta0  1  0.500  0.000  0.000  1.0
  Ta  Ta1  1  0.000  0.500  0.000  1.0
  Ti  Ti2  1  0.500  0.000  0.500  1.0
  Ti  Ti3  1  0.000  0.500  0.500  1.0
  Cu  Cu4  1  0.500  0.500  0.000  1.0
  Cu  Cu5  1  0.000  0.000  0.500  1.0
  Cu  Cu6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.184  0.184  0.505  1.0
  O  O8  1  0.816  0.816  0.495  1.0
  O  O9  1  0.819  0.819  0.870  1.0
  O  O10  1  0.181  0.181  0.130  1.0
  O  O11  1  0.507  0.872  0.311  1.0
  O  O12  1  0.493  0.128  0.689  1.0
  O  O13  1  0.872  0.507  0.311  1.0
  O  O14  1  0.128  0.493  0.689  1.0
  O  O15  1  0.310  0.689  0.183  1.0
  O  O16  1  0.690  0.311  0.817  1.0
  O  O17  1  0.311  0.690  0.817  1.0
  O  O18  1  0.689  0.310  0.183  1.0
[/CIF]
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The structure described by Cu3Ti2Ta2O12 crystallizes in the monoclinic C2/m space group. Ti(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with two equivalent Ti(1)O6 octahedra and corners with four equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-40°. Ta(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra and corners with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles are 40°. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a square co-planar geometry to four equivalent O(4) atoms. In the second Cu site, Cu(2) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. In the third Cu site, Cu(3) is bonded in a square co-planar geometry to four equivalent O(3) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to two equivalent Ti(1) and one Cu(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Ta(1) and one Cu(2) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ta(1), and one Cu(3) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ta(1), and one Cu(1) atom. is represented by the CIF card [CIF]
data_Ta2Ti2(CuO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.488
_cell_length_b   6.488
_cell_length_c   7.508
_cell_angle_alpha   54.986
_cell_angle_beta   54.986
_cell_angle_gamma   70.815
_symmetry_Int_Tables_number   1
_cell_volume   211.993
_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
  Ta  Ta0  1  0.500  0.000  0.000  1.0
  Ta  Ta1  1  0.000  0.500  0.000  1.0
  Ti  Ti2  1  0.500  0.000  0.500  1.0
  Ti  Ti3  1  0.000  0.500  0.500  1.0
  Cu  Cu4  1  0.500  0.500  0.000  1.0
  Cu  Cu5  1  0.000  0.000  0.500  1.0
  Cu  Cu6  1  0.500  0.500  0.500  1.0
  O  O7  1  0.184  0.184  0.505  1.0
  O  O8  1  0.816  0.816  0.495  1.0
  O  O9  1  0.819  0.819  0.870  1.0
  O  O10  1  0.181  0.181  0.130  1.0
  O  O11  1  0.507  0.872  0.311  1.0
  O  O12  1  0.493  0.128  0.689  1.0
  O  O13  1  0.872  0.507  0.311  1.0
  O  O14  1  0.128  0.493  0.689  1.0
  O  O15  1  0.310  0.689  0.183  1.0
  O  O16  1  0.690  0.311  0.817  1.0
  O  O17  1  0.311  0.690  0.817  1.0
  O  O18  1  0.689  0.310  0.183  1.0
[/CIF]
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