The material described by Na3CuO2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted see-saw-like geometry to four equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a linear geometry to two equivalent O(1) atoms. Cu(1) is bonded in a linear geometry to two equivalent O(1) atoms. O(1) is bonded to one Na(2), four equivalent Na(1), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing ONa5Cu octahedra. The corner-sharing octahedral tilt angles range from 3-21°. is represented by the CIF file [CIF]
data_Na3CuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.364
_cell_length_b   9.364
_cell_length_c   4.530
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   397.185
_cell_formula_units_Z   4
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
  Na  Na0  1  0.653  0.978  0.500  1.0
  Na  Na1  1  0.522  0.153  0.000  1.0
  Na  Na2  1  0.853  0.147  0.000  1.0
  Na  Na3  1  0.353  0.353  0.500  1.0
  Na  Na4  1  0.022  0.347  0.500  1.0
  Na  Na5  1  0.153  0.522  0.000  1.0
  Na  Na6  1  0.847  0.478  0.000  1.0
  Na  Na7  1  0.978  0.653  0.500  1.0
  Na  Na8  1  0.647  0.647  0.500  1.0
  Na  Na9  1  0.147  0.853  0.000  1.0
  Na  Na10  1  0.478  0.847  0.000  1.0
  Na  Na11  1  0.347  0.022  0.500  1.0
  Cu  Cu12  1  0.172  0.172  0.000  1.0
  Cu  Cu13  1  0.672  0.328  0.500  1.0
  Cu  Cu14  1  0.328  0.672  0.500  1.0
  Cu  Cu15  1  0.828  0.828  0.000  1.0
  O  O16  1  0.303  0.033  0.000  1.0
  O  O17  1  0.533  0.197  0.500  1.0
  O  O18  1  0.033  0.303  0.000  1.0
  O  O19  1  0.803  0.467  0.500  1.0
  O  O20  1  0.197  0.533  0.500  1.0
  O  O21  1  0.967  0.697  0.000  1.0
  O  O22  1  0.467  0.803  0.500  1.0
  O  O23  1  0.697  0.967  0.000  1.0
[/CIF]
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The material described by Na3CuO2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal P4_2/mnm space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a distorted see-saw-like geometry to four equivalent O(1) atoms. In the second Na site, Na(2) is bonded in a linear geometry to two equivalent O(1) atoms. Cu(1) is bonded in a linear geometry to two equivalent O(1) atoms. O(1) is bonded to one Na(2), four equivalent Na(1), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing ONa5Cu octahedra. The corner-sharing octahedral tilt angles range from 3-21°. is represented by the CIF file [CIF]
data_Na3CuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.364
_cell_length_b   9.364
_cell_length_c   4.530
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   397.185
_cell_formula_units_Z   4
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
  Na  Na0  1  0.653  0.978  0.500  1.0
  Na  Na1  1  0.522  0.153  0.000  1.0
  Na  Na2  1  0.853  0.147  0.000  1.0
  Na  Na3  1  0.353  0.353  0.500  1.0
  Na  Na4  1  0.022  0.347  0.500  1.0
  Na  Na5  1  0.153  0.522  0.000  1.0
  Na  Na6  1  0.847  0.478  0.000  1.0
  Na  Na7  1  0.978  0.653  0.500  1.0
  Na  Na8  1  0.647  0.647  0.500  1.0
  Na  Na9  1  0.147  0.853  0.000  1.0
  Na  Na10  1  0.478  0.847  0.000  1.0
  Na  Na11  1  0.347  0.022  0.500  1.0
  Cu  Cu12  1  0.172  0.172  0.000  1.0
  Cu  Cu13  1  0.672  0.328  0.500  1.0
  Cu  Cu14  1  0.328  0.672  0.500  1.0
  Cu  Cu15  1  0.828  0.828  0.000  1.0
  O  O16  1  0.303  0.033  0.000  1.0
  O  O17  1  0.533  0.197  0.500  1.0
  O  O18  1  0.033  0.303  0.000  1.0
  O  O19  1  0.803  0.467  0.500  1.0
  O  O20  1  0.197  0.533  0.500  1.0
  O  O21  1  0.967  0.697  0.000  1.0
  O  O22  1  0.467  0.803  0.500  1.0
  O  O23  1  0.697  0.967  0.000  1.0
[/CIF]
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