The structure described by YBa2Cu3O8 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with eight equivalent Ba(1)O12 cuboctahedra, faces with five equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Cu(1)O6 octahedra, and faces with four equivalent Cu(2)O5 square pyramids. Y(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form CuO6 octahedra that share corners with four equivalent Cu(1)O6 octahedra, corners with two equivalent Cu(2)O5 square pyramids, and faces with eight equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Cu site, Cu(2) is bonded to one O(2) and four equivalent O(1) atoms to form CuO5 square pyramids that share  a cornercorner with one Cu(1)O6 octahedra, corners with four equivalent Cu(2)O5 square pyramids, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Y(1), and two equivalent Cu(2) atoms. In the second O site, O(2) is bonded to four equivalent Ba(1), one Cu(1), and one Cu(2) atom to form a mixture of distorted corner, edge, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the third O site, O(3) is bonded to four equivalent Ba(1) and two equivalent Cu(1) atoms to form a mixture of distorted corner, edge, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2YCu3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.932
_cell_length_b   3.932
_cell_length_c   11.574
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   178.978
_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  0.169  1.0
  Ba  Ba1  1  0.500  0.500  0.831  1.0
  Y  Y2  1  0.500  0.500  0.500  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Cu  Cu4  1  0.000  0.000  0.346  1.0
  Cu  Cu5  1  0.000  0.000  0.654  1.0
  O  O6  1  0.500  0.000  0.379  1.0
  O  O7  1  0.500  0.000  0.621  1.0
  O  O8  1  0.000  0.500  0.379  1.0
  O  O9  1  0.000  0.500  0.621  1.0
  O  O10  1  0.000  0.000  0.172  1.0
  O  O11  1  0.000  0.000  0.828  1.0
  O  O12  1  0.500  0.000  0.000  1.0
  O  O13  1  0.000  0.500  0.000  1.0
[/CIF]
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The structure described by YBa2Cu3O8 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms to form BaO12 cuboctahedra that share corners with eight equivalent Ba(1)O12 cuboctahedra, faces with five equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Cu(1)O6 octahedra, and faces with four equivalent Cu(2)O5 square pyramids. Y(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form CuO6 octahedra that share corners with four equivalent Cu(1)O6 octahedra, corners with two equivalent Cu(2)O5 square pyramids, and faces with eight equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Cu site, Cu(2) is bonded to one O(2) and four equivalent O(1) atoms to form CuO5 square pyramids that share  a cornercorner with one Cu(1)O6 octahedra, corners with four equivalent Cu(2)O5 square pyramids, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Y(1), and two equivalent Cu(2) atoms. In the second O site, O(2) is bonded to four equivalent Ba(1), one Cu(1), and one Cu(2) atom to form a mixture of distorted corner, edge, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the third O site, O(3) is bonded to four equivalent Ba(1) and two equivalent Cu(1) atoms to form a mixture of distorted corner, edge, and face-sharing OBa4Cu2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2YCu3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.932
_cell_length_b   3.932
_cell_length_c   11.574
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   178.978
_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  0.169  1.0
  Ba  Ba1  1  0.500  0.500  0.831  1.0
  Y  Y2  1  0.500  0.500  0.500  1.0
  Cu  Cu3  1  0.000  0.000  0.000  1.0
  Cu  Cu4  1  0.000  0.000  0.346  1.0
  Cu  Cu5  1  0.000  0.000  0.654  1.0
  O  O6  1  0.500  0.000  0.379  1.0
  O  O7  1  0.500  0.000  0.621  1.0
  O  O8  1  0.000  0.500  0.379  1.0
  O  O9  1  0.000  0.500  0.621  1.0
  O  O10  1  0.000  0.000  0.172  1.0
  O  O11  1  0.000  0.000  0.828  1.0
  O  O12  1  0.500  0.000  0.000  1.0
  O  O13  1  0.000  0.500  0.000  1.0
[/CIF]
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