The material described by Tl2Ba2CaCu2O8 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(1), four equivalent O(2), and four equivalent O(3) atoms. Ca(1) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. Cu(1) is bonded in a rectangular see-saw-like geometry to four equivalent O(2) atoms. Tl(1) is bonded in a distorted linear geometry to one O(3) and five equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1) and five equivalent Tl(1) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Ca(1), and two equivalent Cu(1) atoms to form a mixture of distorted face, corner, and edge-sharing OBa2Ca2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-66°. In the third O site, O(3) is bonded in a 5-coordinate geometry to four equivalent Ba(1) and one Tl(1) atom. is represented by the CIF card [CIF]
data_Ba2CaTl2(CuO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   15.449
_cell_length_b   15.449
_cell_length_c   15.449
_cell_angle_alpha   165.539
_cell_angle_beta   165.539
_cell_angle_gamma   20.506
_symmetry_Int_Tables_number   1
_cell_volume   229.898
_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  0.117  0.117  0.000  1.0
  Ba  Ba1  1  0.883  0.883  0.000  1.0
  Ca  Ca2  1  0.000  0.000  0.000  1.0
  Tl  Tl3  1  0.288  0.288  0.000  1.0
  Tl  Tl4  1  0.712  0.712  0.000  1.0
  Cu  Cu5  1  0.551  0.551  0.000  1.0
  Cu  Cu6  1  0.449  0.449  0.000  1.0
  O  O7  1  0.781  0.781  0.000  1.0
  O  O8  1  0.448  0.948  0.500  1.0
  O  O9  1  0.052  0.552  0.500  1.0
  O  O10  1  0.646  0.646  0.000  1.0
  O  O11  1  0.552  0.052  0.500  1.0
  O  O12  1  0.948  0.448  0.500  1.0
  O  O13  1  0.354  0.354  0.000  1.0
  O  O14  1  0.219  0.219  0.000  1.0
[/CIF]
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The material described by Tl2Ba2CaCu2O8 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(1), four equivalent O(2), and four equivalent O(3) atoms. Ca(1) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. Cu(1) is bonded in a rectangular see-saw-like geometry to four equivalent O(2) atoms. Tl(1) is bonded in a distorted linear geometry to one O(3) and five equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Ba(1) and five equivalent Tl(1) atoms. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Ca(1), and two equivalent Cu(1) atoms to form a mixture of distorted face, corner, and edge-sharing OBa2Ca2Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-66°. In the third O site, O(3) is bonded in a 5-coordinate geometry to four equivalent Ba(1) and one Tl(1) atom. is represented by the CIF card [CIF]
data_Ba2CaTl2(CuO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   15.449
_cell_length_b   15.449
_cell_length_c   15.449
_cell_angle_alpha   165.539
_cell_angle_beta   165.539
_cell_angle_gamma   20.506
_symmetry_Int_Tables_number   1
_cell_volume   229.898
_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  0.117  0.117  0.000  1.0
  Ba  Ba1  1  0.883  0.883  0.000  1.0
  Ca  Ca2  1  0.000  0.000  0.000  1.0
  Tl  Tl3  1  0.288  0.288  0.000  1.0
  Tl  Tl4  1  0.712  0.712  0.000  1.0
  Cu  Cu5  1  0.551  0.551  0.000  1.0
  Cu  Cu6  1  0.449  0.449  0.000  1.0
  O  O7  1  0.781  0.781  0.000  1.0
  O  O8  1  0.448  0.948  0.500  1.0
  O  O9  1  0.052  0.552  0.500  1.0
  O  O10  1  0.646  0.646  0.000  1.0
  O  O11  1  0.552  0.052  0.500  1.0
  O  O12  1  0.948  0.448  0.500  1.0
  O  O13  1  0.354  0.354  0.000  1.0
  O  O14  1  0.219  0.219  0.000  1.0
[/CIF]
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