The structure described by BaCuO2 crystallizes in the orthorhombic Cmcm space group. Ba(1) is bonded in a 7-coordinate geometry to two equivalent O(2) and five equivalent O(1) atoms. Cu(1) is bonded in a square co-planar geometry to one O(1) and three equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to five equivalent Ba(1) and one Cu(1) atom to form distorted OBa5Cu octahedra that share corners with four equivalent O(1)Ba5Cu octahedra, corners with seven equivalent O(2)Ba2Cu3 trigonal bipyramids, edges with eight equivalent O(1)Ba5Cu octahedra, and faces with two equivalent O(2)Ba2Cu3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 8°. In the second O site, O(2) is bonded to two equivalent Ba(1) and three equivalent Cu(1) atoms to form distorted OBa2Cu3 trigonal bipyramids that share corners with seven equivalent O(1)Ba5Cu octahedra, corners with four equivalent O(2)Ba2Cu3 trigonal bipyramids, edges with two equivalent O(2)Ba2Cu3 trigonal bipyramids, and faces with two equivalent O(1)Ba5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-56°. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaCuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.996
_cell_length_b   4.025
_cell_length_c   8.526
_cell_angle_alpha   90.000
_cell_angle_beta   76.448
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   133.330
_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  0.336  0.250  0.327  1.0
  Ba  Ba1  1  0.664  0.750  0.673  1.0
  Cu  Cu2  1  0.062  0.250  0.876  1.0
  Cu  Cu3  1  0.938  0.750  0.124  1.0
  O  O4  1  0.825  0.750  0.351  1.0
  O  O5  1  0.949  0.250  0.102  1.0
  O  O6  1  0.175  0.250  0.649  1.0
  O  O7  1  0.051  0.750  0.898  1.0
[/CIF]
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The structure described by BaCuO2 crystallizes in the orthorhombic Cmcm space group. Ba(1) is bonded in a 7-coordinate geometry to two equivalent O(2) and five equivalent O(1) atoms. Cu(1) is bonded in a square co-planar geometry to one O(1) and three equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to five equivalent Ba(1) and one Cu(1) atom to form distorted OBa5Cu octahedra that share corners with four equivalent O(1)Ba5Cu octahedra, corners with seven equivalent O(2)Ba2Cu3 trigonal bipyramids, edges with eight equivalent O(1)Ba5Cu octahedra, and faces with two equivalent O(2)Ba2Cu3 trigonal bipyramids. The corner-sharing octahedral tilt angles are 8°. In the second O site, O(2) is bonded to two equivalent Ba(1) and three equivalent Cu(1) atoms to form distorted OBa2Cu3 trigonal bipyramids that share corners with seven equivalent O(1)Ba5Cu octahedra, corners with four equivalent O(2)Ba2Cu3 trigonal bipyramids, edges with two equivalent O(2)Ba2Cu3 trigonal bipyramids, and faces with two equivalent O(1)Ba5Cu octahedra. The corner-sharing octahedral tilt angles range from 0-56°. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaCuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.996
_cell_length_b   4.025
_cell_length_c   8.526
_cell_angle_alpha   90.000
_cell_angle_beta   76.448
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   133.330
_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  0.336  0.250  0.327  1.0
  Ba  Ba1  1  0.664  0.750  0.673  1.0
  Cu  Cu2  1  0.062  0.250  0.876  1.0
  Cu  Cu3  1  0.938  0.750  0.124  1.0
  O  O4  1  0.825  0.750  0.351  1.0
  O  O5  1  0.949  0.250  0.102  1.0
  O  O6  1  0.175  0.250  0.649  1.0
  O  O7  1  0.051  0.750  0.898  1.0
[/CIF]
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