The material described by Na4Cu(AsO4)2 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), and three equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), and three equivalent O(1) atoms. Cu(1) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. As(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), three equivalent Na(2), and one As(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Cu(1), and one As(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(2), three equivalent Na(1), and one As(1) atom. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Cu(1), and one As(1) atom to form distorted corner-sharing ONa2CuAs tetrahedra. is represented by the CIF card [CIF]
data_Na4Cu(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.846
_cell_length_b   5.834
_cell_length_c   6.931
_cell_angle_alpha   98.006
_cell_angle_beta   90.811
_cell_angle_gamma   105.895
_symmetry_Int_Tables_number   1
_cell_volume   186.348
_cell_formula_units_Z   1
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  0.287  0.571  0.169  1.0
  Na  Na1  1  0.713  0.429  0.831  1.0
  Na  Na2  1  0.163  0.260  0.576  1.0
  Na  Na3  1  0.837  0.740  0.424  1.0
  Cu  Cu4  1  0.000  0.000  0.000  1.0
  As  As5  1  0.400  0.804  0.734  1.0
  As  As6  1  0.600  0.196  0.266  1.0
  O  O7  1  0.686  0.274  0.508  1.0
  O  O8  1  0.233  0.148  0.240  1.0
  O  O9  1  0.235  0.566  0.845  1.0
  O  O10  1  0.767  0.852  0.760  1.0
  O  O11  1  0.765  0.434  0.155  1.0
  O  O12  1  0.678  0.936  0.167  1.0
  O  O13  1  0.322  0.064  0.833  1.0
  O  O14  1  0.314  0.726  0.492  1.0
[/CIF]
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The material described by Na4Cu(AsO4)2 crystallizes in the triclinic P-1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(4), and three equivalent O(3) atoms. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), and three equivalent O(1) atoms. Cu(1) is bonded in a square co-planar geometry to two equivalent O(2) and two equivalent O(4) atoms. As(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), three equivalent Na(2), and one As(1) atom. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Cu(1), and one As(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Na(2), three equivalent Na(1), and one As(1) atom. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Cu(1), and one As(1) atom to form distorted corner-sharing ONa2CuAs tetrahedra. is represented by the CIF card [CIF]
data_Na4Cu(AsO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.846
_cell_length_b   5.834
_cell_length_c   6.931
_cell_angle_alpha   98.006
_cell_angle_beta   90.811
_cell_angle_gamma   105.895
_symmetry_Int_Tables_number   1
_cell_volume   186.348
_cell_formula_units_Z   1
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  0.287  0.571  0.169  1.0
  Na  Na1  1  0.713  0.429  0.831  1.0
  Na  Na2  1  0.163  0.260  0.576  1.0
  Na  Na3  1  0.837  0.740  0.424  1.0
  Cu  Cu4  1  0.000  0.000  0.000  1.0
  As  As5  1  0.400  0.804  0.734  1.0
  As  As6  1  0.600  0.196  0.266  1.0
  O  O7  1  0.686  0.274  0.508  1.0
  O  O8  1  0.233  0.148  0.240  1.0
  O  O9  1  0.235  0.566  0.845  1.0
  O  O10  1  0.767  0.852  0.760  1.0
  O  O11  1  0.765  0.434  0.155  1.0
  O  O12  1  0.678  0.936  0.167  1.0
  O  O13  1  0.322  0.064  0.833  1.0
  O  O14  1  0.314  0.726  0.492  1.0
[/CIF]
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