The material structure described by Na2Ta2O5 crystallizes in the orthorhombic Ima2 space group. Na(1) is bonded in a 8-coordinate geometry to one O(3), three equivalent O(2), and four equivalent O(1) atoms. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 5°. In the second Ta site, Ta(2) is bonded in a rectangular see-saw-like geometry to two equivalent O(2) and two equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Na(1) and two equivalent Ta(1) atoms to form a mixture of distorted edge, face, and corner-sharing ONa4Ta2 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Na(1), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Na(1) and two equivalent Ta(2) atoms. is represented by the CIF file [CIF]
data_Na2Ta2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.862
_cell_length_b   8.862
_cell_length_c   8.862
_cell_angle_alpha   143.071
_cell_angle_beta   142.818
_cell_angle_gamma   53.409
_symmetry_Int_Tables_number   1
_cell_volume   251.139
_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  0.896  0.380  0.513  1.0
  Na  Na1  1  0.104  0.617  0.484  1.0
  Na  Na2  1  0.366  0.880  0.484  1.0
  Na  Na3  1  0.634  0.117  0.513  1.0
  Ta  Ta4  1  0.000  0.996  0.996  1.0
  Ta  Ta5  1  0.500  0.496  0.996  1.0
  Ta  Ta6  1  0.741  0.732  0.973  1.0
  Ta  Ta7  1  0.259  0.232  0.991  1.0
  O  O8  1  0.255  0.252  0.495  1.0
  O  O9  1  0.745  0.240  0.997  1.0
  O  O10  1  0.257  0.752  0.997  1.0
  O  O11  1  0.743  0.740  0.495  1.0
  O  O12  1  0.901  0.862  0.018  1.0
  O  O13  1  0.099  0.117  0.961  1.0
  O  O14  1  0.344  0.362  0.961  1.0
  O  O15  1  0.656  0.617  0.018  1.0
  O  O16  1  0.513  0.469  0.482  1.0
  O  O17  1  0.487  0.969  0.956  1.0
[/CIF]
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The material structure described by Na2Ta2O5 crystallizes in the orthorhombic Ima2 space group. Na(1) is bonded in a 8-coordinate geometry to one O(3), three equivalent O(2), and four equivalent O(1) atoms. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 5°. In the second Ta site, Ta(2) is bonded in a rectangular see-saw-like geometry to two equivalent O(2) and two equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Na(1) and two equivalent Ta(1) atoms to form a mixture of distorted edge, face, and corner-sharing ONa4Ta2 octahedra. The corner-sharing octahedra are not tilted. In the second O site, O(2) is bonded in a 5-coordinate geometry to three equivalent Na(1), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to two equivalent Na(1) and two equivalent Ta(2) atoms. is represented by the CIF file [CIF]
data_Na2Ta2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.862
_cell_length_b   8.862
_cell_length_c   8.862
_cell_angle_alpha   143.071
_cell_angle_beta   142.818
_cell_angle_gamma   53.409
_symmetry_Int_Tables_number   1
_cell_volume   251.139
_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  0.896  0.380  0.513  1.0
  Na  Na1  1  0.104  0.617  0.484  1.0
  Na  Na2  1  0.366  0.880  0.484  1.0
  Na  Na3  1  0.634  0.117  0.513  1.0
  Ta  Ta4  1  0.000  0.996  0.996  1.0
  Ta  Ta5  1  0.500  0.496  0.996  1.0
  Ta  Ta6  1  0.741  0.732  0.973  1.0
  Ta  Ta7  1  0.259  0.232  0.991  1.0
  O  O8  1  0.255  0.252  0.495  1.0
  O  O9  1  0.745  0.240  0.997  1.0
  O  O10  1  0.257  0.752  0.997  1.0
  O  O11  1  0.743  0.740  0.495  1.0
  O  O12  1  0.901  0.862  0.018  1.0
  O  O13  1  0.099  0.117  0.961  1.0
  O  O14  1  0.344  0.362  0.961  1.0
  O  O15  1  0.656  0.617  0.018  1.0
  O  O16  1  0.513  0.469  0.482  1.0
  O  O17  1  0.487  0.969  0.956  1.0
[/CIF]
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