data_Ba2Y(CuO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.67
_cell_length_b   13.67
_cell_length_c   3.83
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   163.72
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ba2Y(CuO2)4
_chemical_formula_sum   'Ba2 Y1 Cu4 O8'
_cell_volume   200.91
_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  0.94  0.86  0.0  1.0
  Ba  Ba1  1  0.94  0.14  0.0  1.0
  Y  Y14  1  0.0  0.0  0.0  1.0
  Cu  Cu2  1  0.94  0.67  0.92  1.0
  Cu  Cu3  1  0.94  0.77  0.92  1.0
  Cu  Cu4  1  0.94  0.23  0.92  1.0
  Cu  Cu5  1  0.94  0.33  0.92  1.0
  O  O6  1  0.94  0.42  0.0  1.0
  O  O7  1  0.94  0.94  0.92  1.0
  O  O8  1  0.94  0.64  0.92  1.0
  O  O9  1  0.94  0.11  0.92  1.0
  O  O10  1  0.94  0.89  0.92  1.0
  O  O11  1  0.94  0.36  0.92  1.0
  O  O12  1  0.94  0.06  0.92  1.0
  O  O13  1  0.94  0.58  0.0  1.0

data_Ba2Y(CuO2)4
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.83
_cell_length_b   3.87
_cell_length_c   13.67
_cell_angle_alpha   98.14
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ba2Y(CuO2)4
_chemical_formula_sum   'Ba2 Y1 Cu4 O8'
_cell_volume   200.91
_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  -0.0  0.86  0.79  1.0
  Ba  Ba1  1  -0.0  0.14  0.08  1.0
  Y  Y2  1  0.0  0.0  0.0  1.0
  Cu  Cu3  1  0.92  0.23  0.17  1.0
  Cu  Cu4  1  0.92  0.33  0.27  1.0
  Cu  Cu5  1  0.92  0.67  0.61  1.0
  Cu  Cu6  1  0.92  0.77  0.71  1.0
  O  O7  1  -0.0  0.42  0.36  1.0
  O  O8  1  -0.0  0.58  0.51  1.0
  O  O9  1  0.92  0.06  0.99  1.0
  O  O10  1  0.92  0.11  0.04  1.0
  O  O11  1  0.92  0.36  0.29  1.0
  O  O12  1  0.92  0.64  0.58  1.0
  O  O13  1  0.92  0.89  0.83  1.0
  O  O14  1  0.92  0.94  0.88  1.0

Ba Ba Y Cu Cu Cu Cu O O O O O O O O
Ba Ba Y Cu Cu Cu Cu O O O O O O O O 0 11 o o - 0 4 o o - 1 10 o o - 1 5 o o - 2 8 - - - 3 9 o o o 3 4 o o o 5 6 o o o 6 12 o o o 7 12 o o - 9 14 o o + 10 13 o o o 
YBa2Cu4O8 crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two copper;molecular oxygen molecules and one Ba2Y(CuO2)2 cluster. In the Ba2Y(CuO2)2 cluster, there are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted single-bond geometry to one Cu(2) and one O(5) atom. The Ba(1)-Cu(2) bond length is 1.22 Å. The Ba(1)-O(5) bond length is 0.58 Å. In the second Ba site, Ba(2) is bonded in a distorted single-bond geometry to one Cu(3) and one O(4) atom. The Ba(2)-Cu(3) bond length is 1.22 Å. The Ba(2)-O(4) bond length is 0.58 Å. Y(1) is bonded in a 2-coordinate geometry to one O(2), one O(5), and one O(7) atom. The Y(1)-O(2) bond length is 0.41 Å. The Y(1)-O(5) bond length is 0.75 Å. The Y(1)-O(7) bond length is 1.65 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(2) is bonded in a single-bond geometry to one Ba(1) atom. In the second Cu site, Cu(3) is bonded in a single-bond geometry to one Ba(2) atom. There are four inequivalent O sites. In the first O site, O(2) is bonded in a single-bond geometry to one Y(1) and one O(7) atom. The O(2)-O(7) bond length is 1.51 Å. In the second O site, O(4) is bonded in a single-bond geometry to one Ba(2) and one O(7) atom. The O(4)-O(7) bond length is 0.72 Å. In the third O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Ba(1) and one Y(1) atom. In the fourth O site, O(7) is bonded in a 3-coordinate geometry to one Y(1), one O(2), and one O(4) atom.