The compound described by Na3CuO2 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 3-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one O(1) and two equivalent O(2) atoms. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. Cu(1) is bonded in a linear geometry to one O(1) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), two equivalent Na(1), two equivalent Na(3), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing ONa5Cu octahedra. The corner-sharing octahedral tilt angles are 65°. In the second O site, O(2) is bonded in a 7-coordinate geometry to two equivalent Na(1), two equivalent Na(2), two equivalent Na(3), and one Cu(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3CuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.686
_cell_length_b   5.751
_cell_length_c   7.652
_cell_angle_alpha   68.528
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   355.718
_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  0.968  0.754  0.501  1.0
  Na  Na1  1  0.530  0.742  0.624  1.0
  Na  Na2  1  0.716  0.238  0.688  1.0
  Na  Na3  1  0.030  0.258  0.876  1.0
  Na  Na4  1  0.216  0.762  0.812  1.0
  Na  Na5  1  0.468  0.246  0.999  1.0
  Na  Na6  1  0.532  0.754  0.001  1.0
  Na  Na7  1  0.784  0.238  0.188  1.0
  Na  Na8  1  0.970  0.742  0.124  1.0
  Na  Na9  1  0.284  0.762  0.312  1.0
  Na  Na10  1  0.470  0.258  0.376  1.0
  Na  Na11  1  0.032  0.246  0.499  1.0
  Cu  Cu12  1  0.322  0.295  0.674  1.0
  Cu  Cu13  1  0.822  0.705  0.826  1.0
  Cu  Cu14  1  0.178  0.295  0.174  1.0
  Cu  Cu15  1  0.678  0.705  0.326  1.0
  O  O16  1  0.177  0.529  0.618  1.0
  O  O17  1  0.464  0.055  0.721  1.0
  O  O18  1  0.677  0.471  0.882  1.0
  O  O19  1  0.964  0.945  0.779  1.0
  O  O20  1  0.036  0.055  0.221  1.0
  O  O21  1  0.323  0.529  0.118  1.0
  O  O22  1  0.536  0.945  0.279  1.0
  O  O23  1  0.823  0.471  0.382  1.0
[/CIF]
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The compound described by Na3CuO2 crystallizes in the monoclinic P2_1/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded in a 3-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. In the second Na site, Na(2) is bonded in a 3-coordinate geometry to one O(1) and two equivalent O(2) atoms. In the third Na site, Na(3) is bonded in a 4-coordinate geometry to two equivalent O(1) and two equivalent O(2) atoms. Cu(1) is bonded in a linear geometry to one O(1) and one O(2) atom. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Na(2), two equivalent Na(1), two equivalent Na(3), and one Cu(1) atom to form a mixture of distorted corner and edge-sharing ONa5Cu octahedra. The corner-sharing octahedral tilt angles are 65°. In the second O site, O(2) is bonded in a 7-coordinate geometry to two equivalent Na(1), two equivalent Na(2), two equivalent Na(3), and one Cu(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na3CuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.686
_cell_length_b   5.751
_cell_length_c   7.652
_cell_angle_alpha   68.528
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   355.718
_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  0.968  0.754  0.501  1.0
  Na  Na1  1  0.530  0.742  0.624  1.0
  Na  Na2  1  0.716  0.238  0.688  1.0
  Na  Na3  1  0.030  0.258  0.876  1.0
  Na  Na4  1  0.216  0.762  0.812  1.0
  Na  Na5  1  0.468  0.246  0.999  1.0
  Na  Na6  1  0.532  0.754  0.001  1.0
  Na  Na7  1  0.784  0.238  0.188  1.0
  Na  Na8  1  0.970  0.742  0.124  1.0
  Na  Na9  1  0.284  0.762  0.312  1.0
  Na  Na10  1  0.470  0.258  0.376  1.0
  Na  Na11  1  0.032  0.246  0.499  1.0
  Cu  Cu12  1  0.322  0.295  0.674  1.0
  Cu  Cu13  1  0.822  0.705  0.826  1.0
  Cu  Cu14  1  0.178  0.295  0.174  1.0
  Cu  Cu15  1  0.678  0.705  0.326  1.0
  O  O16  1  0.177  0.529  0.618  1.0
  O  O17  1  0.464  0.055  0.721  1.0
  O  O18  1  0.677  0.471  0.882  1.0
  O  O19  1  0.964  0.945  0.779  1.0
  O  O20  1  0.036  0.055  0.221  1.0
  O  O21  1  0.323  0.529  0.118  1.0
  O  O22  1  0.536  0.945  0.279  1.0
  O  O23  1  0.823  0.471  0.382  1.0
[/CIF]
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