The material described by Na5NbO5 crystallizes in the monoclinic C2/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form distorted NaO4 trigonal pyramids that share corners with four equivalent Na(2)O5 square pyramids, corners with two equivalent Na(3)O5 trigonal bipyramids, corners with two equivalent Nb(1)O5 trigonal bipyramids,  a cornercorner with one Na(1)O4 trigonal pyramid, edges with two equivalent Na(2)O5 square pyramids,  an edgeedge with one Na(3)O5 trigonal bipyramid,  an edgeedge with one Nb(1)O5 trigonal bipyramid, and  an edgeedge with one Na(1)O4 trigonal pyramid. In the second Na site, Na(2) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO5 square pyramids that share  a cornercorner with one Na(2)O5 square pyramid,  a cornercorner with one Na(3)O5 trigonal bipyramid, corners with three equivalent Nb(1)O5 trigonal bipyramids, corners with four equivalent Na(1)O4 trigonal pyramids, edges with two equivalent Na(2)O5 square pyramids,  an edgeedge with one Nb(1)O5 trigonal bipyramid, edges with two equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(1)O4 trigonal pyramids. In the third Na site, Na(3) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO5 trigonal bipyramids that share corners with two equivalent Na(2)O5 square pyramids,  a cornercorner with one Nb(1)O5 trigonal bipyramid, corners with four equivalent Na(1)O4 trigonal pyramids, edges with four equivalent Na(2)O5 square pyramids, edges with two equivalent Nb(1)O5 trigonal bipyramids, and edges with two equivalent Na(1)O4 trigonal pyramids. Nb(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form NbO5 trigonal bipyramids that share corners with six equivalent Na(2)O5 square pyramids,  a cornercorner with one Na(3)O5 trigonal bipyramid, corners with four equivalent Na(1)O4 trigonal pyramids, edges with two equivalent Na(2)O5 square pyramids, edges with two equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(1)O4 trigonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Nb(1) atom to form distorted ONa5Nb octahedra that share corners with four equivalent O(3)Na5Nb octahedra, corners with two equivalent O(2)Na4Nb square pyramids, edges with four equivalent O(3)Na5Nb octahedra, and edges with four equivalent O(2)Na4Nb square pyramids. The corner-sharing octahedral tilt angles range from 16-30°. In the second O site, O(2) is bonded to one Na(1), one Na(3), two equivalent Na(2), and one Nb(1) atom to form distorted ONa4Nb square pyramids that share  a cornercorner with one O(1)Na5Nb octahedra, corners with two equivalent O(3)Na5Nb octahedra, corners with two equivalent O(2)Na4Nb square pyramids, edges with two equivalent O(1)Na5Nb octahedra, edges with four equivalent O(3)Na5Nb octahedra, and  an edgeedge with one O(2)Na4Nb square pyramid. The corner-sharing octahedral tilt angles range from 30-68°. In the third O site, O(3) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Nb(1) atom to form distorted ONa5Nb octahedra that share corners with two equivalent O(1)Na5Nb octahedra, corners with two equivalent O(3)Na5Nb octahedra, corners with two equivalent O(2)Na4Nb square pyramids, edges with two equivalent O(1)Na5Nb octahedra, edges with two equivalent O(3)Na5Nb octahedra, and edges with four equivalent O(2)Na4Nb square pyramids. The corner-sharing octahedral tilt angles range from 9-32°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na5NbO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.985
_cell_length_b   5.985
_cell_length_c   9.998
_cell_angle_alpha   81.383
_cell_angle_beta   81.383
_cell_angle_gamma   116.818
_symmetry_Int_Tables_number   1
_cell_volume   306.221
_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  0.677  0.996  0.078  1.0
  Na  Na1  1  0.004  0.323  0.422  1.0
  Na  Na2  1  0.785  0.556  0.950  1.0
  Na  Na3  1  0.444  0.215  0.550  1.0
  Na  Na4  1  0.215  0.444  0.050  1.0
  Na  Na5  1  0.556  0.785  0.450  1.0
  Na  Na6  1  0.669  0.331  0.250  1.0
  Na  Na7  1  0.331  0.669  0.750  1.0
  Na  Na8  1  0.996  0.677  0.578  1.0
  Na  Na9  1  0.323  0.004  0.922  1.0
  Nb  Nb10  1  0.092  0.908  0.250  1.0
  Nb  Nb11  1  0.908  0.092  0.750  1.0
  O  O12  1  0.096  0.904  0.750  1.0
  O  O13  1  0.904  0.096  0.250  1.0
  O  O14  1  0.695  0.037  0.617  1.0
  O  O15  1  0.963  0.305  0.883  1.0
  O  O16  1  0.407  0.192  0.103  1.0
  O  O17  1  0.808  0.593  0.397  1.0
  O  O18  1  0.593  0.808  0.897  1.0
  O  O19  1  0.192  0.407  0.603  1.0
  O  O20  1  0.305  0.963  0.383  1.0
  O  O21  1  0.037  0.695  0.117  1.0
[/CIF]
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The material described by Na5NbO5 crystallizes in the monoclinic C2/c space group. There are three inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form distorted NaO4 trigonal pyramids that share corners with four equivalent Na(2)O5 square pyramids, corners with two equivalent Na(3)O5 trigonal bipyramids, corners with two equivalent Nb(1)O5 trigonal bipyramids,  a cornercorner with one Na(1)O4 trigonal pyramid, edges with two equivalent Na(2)O5 square pyramids,  an edgeedge with one Na(3)O5 trigonal bipyramid,  an edgeedge with one Nb(1)O5 trigonal bipyramid, and  an edgeedge with one Na(1)O4 trigonal pyramid. In the second Na site, Na(2) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO5 square pyramids that share  a cornercorner with one Na(2)O5 square pyramid,  a cornercorner with one Na(3)O5 trigonal bipyramid, corners with three equivalent Nb(1)O5 trigonal bipyramids, corners with four equivalent Na(1)O4 trigonal pyramids, edges with two equivalent Na(2)O5 square pyramids,  an edgeedge with one Nb(1)O5 trigonal bipyramid, edges with two equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(1)O4 trigonal pyramids. In the third Na site, Na(3) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form distorted NaO5 trigonal bipyramids that share corners with two equivalent Na(2)O5 square pyramids,  a cornercorner with one Nb(1)O5 trigonal bipyramid, corners with four equivalent Na(1)O4 trigonal pyramids, edges with four equivalent Na(2)O5 square pyramids, edges with two equivalent Nb(1)O5 trigonal bipyramids, and edges with two equivalent Na(1)O4 trigonal pyramids. Nb(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form NbO5 trigonal bipyramids that share corners with six equivalent Na(2)O5 square pyramids,  a cornercorner with one Na(3)O5 trigonal bipyramid, corners with four equivalent Na(1)O4 trigonal pyramids, edges with two equivalent Na(2)O5 square pyramids, edges with two equivalent Na(3)O5 trigonal bipyramids, and edges with two equivalent Na(1)O4 trigonal pyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Nb(1) atom to form distorted ONa5Nb octahedra that share corners with four equivalent O(3)Na5Nb octahedra, corners with two equivalent O(2)Na4Nb square pyramids, edges with four equivalent O(3)Na5Nb octahedra, and edges with four equivalent O(2)Na4Nb square pyramids. The corner-sharing octahedral tilt angles range from 16-30°. In the second O site, O(2) is bonded to one Na(1), one Na(3), two equivalent Na(2), and one Nb(1) atom to form distorted ONa4Nb square pyramids that share  a cornercorner with one O(1)Na5Nb octahedra, corners with two equivalent O(3)Na5Nb octahedra, corners with two equivalent O(2)Na4Nb square pyramids, edges with two equivalent O(1)Na5Nb octahedra, edges with four equivalent O(3)Na5Nb octahedra, and  an edgeedge with one O(2)Na4Nb square pyramid. The corner-sharing octahedral tilt angles range from 30-68°. In the third O site, O(3) is bonded to one Na(3), two equivalent Na(1), two equivalent Na(2), and one Nb(1) atom to form distorted ONa5Nb octahedra that share corners with two equivalent O(1)Na5Nb octahedra, corners with two equivalent O(3)Na5Nb octahedra, corners with two equivalent O(2)Na4Nb square pyramids, edges with two equivalent O(1)Na5Nb octahedra, edges with two equivalent O(3)Na5Nb octahedra, and edges with four equivalent O(2)Na4Nb square pyramids. The corner-sharing octahedral tilt angles range from 9-32°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na5NbO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.985
_cell_length_b   5.985
_cell_length_c   9.998
_cell_angle_alpha   81.383
_cell_angle_beta   81.383
_cell_angle_gamma   116.818
_symmetry_Int_Tables_number   1
_cell_volume   306.221
_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  0.677  0.996  0.078  1.0
  Na  Na1  1  0.004  0.323  0.422  1.0
  Na  Na2  1  0.785  0.556  0.950  1.0
  Na  Na3  1  0.444  0.215  0.550  1.0
  Na  Na4  1  0.215  0.444  0.050  1.0
  Na  Na5  1  0.556  0.785  0.450  1.0
  Na  Na6  1  0.669  0.331  0.250  1.0
  Na  Na7  1  0.331  0.669  0.750  1.0
  Na  Na8  1  0.996  0.677  0.578  1.0
  Na  Na9  1  0.323  0.004  0.922  1.0
  Nb  Nb10  1  0.092  0.908  0.250  1.0
  Nb  Nb11  1  0.908  0.092  0.750  1.0
  O  O12  1  0.096  0.904  0.750  1.0
  O  O13  1  0.904  0.096  0.250  1.0
  O  O14  1  0.695  0.037  0.617  1.0
  O  O15  1  0.963  0.305  0.883  1.0
  O  O16  1  0.407  0.192  0.103  1.0
  O  O17  1  0.808  0.593  0.397  1.0
  O  O18  1  0.593  0.808  0.897  1.0
  O  O19  1  0.192  0.407  0.603  1.0
  O  O20  1  0.305  0.963  0.383  1.0
  O  O21  1  0.037  0.695  0.117  1.0
[/CIF]
.