data_BaCuSeO
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.31
_cell_length_b   4.31
_cell_length_c   9.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaCuSeO
_chemical_formula_sum   'Ba2 Cu2 Se2 O2'
_cell_volume   181.67
_cell_formula_units_Z   2
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  0.15  0.37  1.0
  Ba  Ba1  1  0.15  0.0  0.41  1.0
  Cu  Cu2  1  0.15  0.15  0.89  1.0
  Cu  Cu3  1  0.0  0.0  0.89  1.0
  Se  Se4  1  0.15  0.0  0.62  1.0
  Se  Se5  1  0.0  0.15  0.17  1.0
  O  O6  1  0.15  0.15  0.0  1.0
  O  O7  1  0.0  0.0  0.0  1.0

data_BaCuSeO
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.09
_cell_length_b   6.09
_cell_length_c   9.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   BaCuSeO
_chemical_formula_sum   'Ba4 Cu4 Se4 O4'
_cell_volume   363.35
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.0  0.0  0.37  1.0
  Ba  Ba1  2  0.15  0.0  0.41  1.0
  Cu  Cu2  4  0.08  0.08  0.89  1.0
  Se  Se3  2  0.0  0.0  0.17  1.0
  Se  Se4  2  0.15  0.0  0.62  1.0
  O  O5  4  0.08  0.08  -0.0  1.0

Ba Ba Cu Cu Se Se O O
Ba Ba Cu Cu Se Se O O 0 1 o o o 0 5 o o o 1 4 o o o 2 3 o o o 2 6 o o + 3 7 o o + 5 7 o o o 5 6 o o o 6 7 o o o 
BaCuSeO crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two BaCuSeO clusters. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted water-like geometry to one Ba(2) and one Se(2) atom. The Ba(1)-Ba(2) bond length is 1.02 Å. The Ba(1)-Se(2) bond length is 2.02 Å. In the second Ba site, Ba(2) is bonded in a distorted water-like geometry to one Ba(1) and one Se(1) atom. The Ba(2)-Se(1) bond length is 2.02 Å. Cu(1) is bonded in a distorted single-bond geometry to one O(1) atom. The Cu(1)-O(1) bond length is 1.07 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a single-bond geometry to one Ba(2) atom. In the second Se site, Se(2) is bonded in a 3-coordinate geometry to one Ba(1) and two equivalent O(1) atoms. Both Se(2)-O(1) bond lengths are 1.75 Å. O(1) is bonded in a distorted single-bond geometry to one Cu(1) and one Se(2) atom.