The compound described by Na2CuO2 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to two equivalent O(2) and three equivalent O(1) atoms. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing NaO4 tetrahedra. Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to two equivalent Na(2), three equivalent Na(1), and two equivalent Cu(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Cu(1) atoms to form a mixture of corner and edge-sharing ONa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 56°. is represented by the CIF card [CIF]
data_Na2CuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.387
_cell_length_b   5.387
_cell_length_c   8.241
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   148.223
_symmetry_Int_Tables_number   1
_cell_volume   125.935
_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
  Na  Na0  1  0.147  0.853  0.332  1.0
  Na  Na1  1  0.394  0.606  0.151  1.0
  Na  Na2  1  0.853  0.147  0.832  1.0
  Na  Na3  1  0.606  0.394  0.651  1.0
  Cu  Cu4  1  0.122  0.878  0.997  1.0
  Cu  Cu5  1  0.878  0.122  0.497  1.0
  O  O6  1  0.275  0.725  0.597  1.0
  O  O7  1  0.517  0.483  0.909  1.0
  O  O8  1  0.483  0.517  0.409  1.0
  O  O9  1  0.725  0.275  0.097  1.0
[/CIF]
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The compound described by Na2CuO2 crystallizes in the orthorhombic Cmc2_1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 5-coordinate geometry to two equivalent O(2) and three equivalent O(1) atoms. In the second Na site, Na(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted corner-sharing NaO4 tetrahedra. Cu(1) is bonded in a square co-planar geometry to two equivalent O(1) and two equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 7-coordinate geometry to two equivalent Na(2), three equivalent Na(1), and two equivalent Cu(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Cu(1) atoms to form a mixture of corner and edge-sharing ONa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 56°. is represented by the CIF card [CIF]
data_Na2CuO2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.387
_cell_length_b   5.387
_cell_length_c   8.241
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   148.223
_symmetry_Int_Tables_number   1
_cell_volume   125.935
_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
  Na  Na0  1  0.147  0.853  0.332  1.0
  Na  Na1  1  0.394  0.606  0.151  1.0
  Na  Na2  1  0.853  0.147  0.832  1.0
  Na  Na3  1  0.606  0.394  0.651  1.0
  Cu  Cu4  1  0.122  0.878  0.997  1.0
  Cu  Cu5  1  0.878  0.122  0.497  1.0
  O  O6  1  0.275  0.725  0.597  1.0
  O  O7  1  0.517  0.483  0.909  1.0
  O  O8  1  0.483  0.517  0.409  1.0
  O  O9  1  0.725  0.275  0.097  1.0
[/CIF]
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