The compound described by Na2Ni2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form NaO6 octahedra that share  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(5), one O(7), and one O(8) atom. In the fourth Na site, Na(4) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(8), and one O(9) atom. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(8) atom to form NiO6 octahedra that share  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(3), one O(4), one O(6), and one O(8) atom to form NiO6 octahedra that share  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. In the third Ni site, Ni(3) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), and one O(9) atom to form NiO6 octahedra that share  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. In the fourth Ni site, Ni(4) is bonded to one O(10), one O(3), one O(4), one O(7), one O(8), and one O(9) atom to form NiO6 octahedra that share  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), one Ni(1), one Ni(2), and one Ni(3) atom to form distorted ONaNi3 trigonal pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(4)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(10)Na3Ni2 square pyramids,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid, and  an edgeedge with one O(5)Na3Ni2 square pyramid. In the second O site, O(2) is bonded to one Na(1), one Na(3), one Na(4), one Ni(1), and one Ni(3) atom to form distorted ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(4)Na3Ni2 square pyramids, corners with two equivalent O(5)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the third O site, O(3) is bonded to one Na(2), one Na(4), one Ni(1), one Ni(2), and one Ni(4) atom to form distorted ONa2Ni3 square pyramids that share  a cornercorner with one O(10)Na3Ni2 square pyramid, corners with two equivalent O(8)Na2Ni3 square pyramids, corners with two equivalent O(5)Na3Ni2 square pyramids, corners with three equivalent O(9)Na3Ni2 square pyramids,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid, edges with two equivalent O(6)Na2Ni3 square pyramids, edges with two equivalent O(4)Na3Ni2 square pyramids, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Na(4), one Ni(2), and one Ni(4) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(8)Na2Ni3 square pyramid, corners with two equivalent O(10)Na3Ni2 square pyramids, corners with two equivalent O(2)Na3Ni2 square pyramids, corners with three equivalent O(6)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with two equivalent O(9)Na3Ni2 square pyramids. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Na(3), one Ni(1), and one Ni(3) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(3)Na2Ni3 square pyramids, corners with two equivalent O(2)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the sixth O site, O(6) is bonded to one Na(2), one Na(4), one Ni(1), one Ni(2), and one Ni(3) atom to form ONa2Ni3 square pyramids that share  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with three equivalent O(4)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, edges with two equivalent O(3)Na2Ni3 square pyramids, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(3), one Ni(3), and one Ni(4) atom. In the eighth O site, O(8) is bonded to one Na(3), one Na(4), one Ni(1), one Ni(2), and one Ni(4) atom to form ONa2Ni3 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(4)Na3Ni2 square pyramid, corners with two equivalent O(3)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the ninth O site, O(9) is bonded to one Na(1), one Na(2), one Na(4), one Ni(3), and one Ni(4) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid, corners with three equivalent O(3)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, and edges with two equivalent O(4)Na3Ni2 square pyramids. In the tenth O site, O(10) is bonded to one Na(1), one Na(2), one Na(3), one Ni(2), and one Ni(4) atom to form distorted ONa3Ni2 square pyramids that share  a cornercorner with one O(3)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(4)Na3Ni2 square pyramids, corners with two equivalent O(1)NaNi3 trigonal pyramids,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, and  an edgeedge with one O(9)Na3Ni2 square pyramid. is represented by the CIF file [CIF]
data_Na2Ni2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.963
_cell_length_b   6.445
_cell_length_c   6.992
_cell_angle_alpha   110.719
_cell_angle_beta   95.785
_cell_angle_gamma   105.698
_symmetry_Int_Tables_number   1
_cell_volume   196.534
_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  0.200  0.392  0.407  1.0
  Na  Na1  1  0.564  0.694  0.204  1.0
  Na  Na2  1  0.847  0.109  0.601  1.0
  Na  Na3  1  0.982  0.499  0.011  1.0
  Ni  Ni4  1  0.402  0.805  0.801  1.0
  Ni  Ni5  1  0.998  0.997  0.996  1.0
  Ni  Ni6  1  0.802  0.602  0.601  1.0
  Ni  Ni7  1  0.596  0.199  0.197  1.0
  O  O8  1  0.097  0.906  0.727  1.0
  O  O9  1  0.103  0.521  0.711  1.0
  O  O10  1  0.302  0.892  0.071  1.0
  O  O11  1  0.293  0.286  0.093  1.0
  O  O12  1  0.529  0.741  0.550  1.0
  O  O13  1  0.703  0.694  0.872  1.0
  O  O14  1  0.564  0.286  0.477  1.0
  O  O15  1  0.701  0.108  0.925  1.0
  O  O16  1  0.844  0.512  0.319  1.0
  O  O17  1  0.866  0.055  0.245  1.0
[/CIF]
.
The compound described by Na2Ni2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(10), one O(2), one O(4), one O(5), one O(7), and one O(9) atom to form NaO6 octahedra that share  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with two equivalent Ni(3)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to one O(10), one O(3), one O(4), one O(5), one O(6), and one O(9) atom. In the third Na site, Na(3) is bonded in a 6-coordinate geometry to one O(1), one O(10), one O(2), one O(5), one O(7), and one O(8) atom. In the fourth Na site, Na(4) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(6), one O(8), and one O(9) atom. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(8) atom to form NiO6 octahedra that share  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. In the second Ni site, Ni(2) is bonded to one O(1), one O(10), one O(3), one O(4), one O(6), and one O(8) atom to form NiO6 octahedra that share  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(4)O6 octahedra. In the third Ni site, Ni(3) is bonded to one O(1), one O(2), one O(5), one O(6), one O(7), and one O(9) atom to form NiO6 octahedra that share  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. In the fourth Ni site, Ni(4) is bonded to one O(10), one O(3), one O(4), one O(7), one O(8), and one O(9) atom to form NiO6 octahedra that share  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. There are ten inequivalent O sites. In the first O site, O(1) is bonded to one Na(3), one Ni(1), one Ni(2), and one Ni(3) atom to form distorted ONaNi3 trigonal pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(4)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(10)Na3Ni2 square pyramids,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid, and  an edgeedge with one O(5)Na3Ni2 square pyramid. In the second O site, O(2) is bonded to one Na(1), one Na(3), one Na(4), one Ni(1), and one Ni(3) atom to form distorted ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(4)Na3Ni2 square pyramids, corners with two equivalent O(5)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the third O site, O(3) is bonded to one Na(2), one Na(4), one Ni(1), one Ni(2), and one Ni(4) atom to form distorted ONa2Ni3 square pyramids that share  a cornercorner with one O(10)Na3Ni2 square pyramid, corners with two equivalent O(8)Na2Ni3 square pyramids, corners with two equivalent O(5)Na3Ni2 square pyramids, corners with three equivalent O(9)Na3Ni2 square pyramids,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid, edges with two equivalent O(6)Na2Ni3 square pyramids, edges with two equivalent O(4)Na3Ni2 square pyramids, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the fourth O site, O(4) is bonded to one Na(1), one Na(2), one Na(4), one Ni(2), and one Ni(4) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(8)Na2Ni3 square pyramid, corners with two equivalent O(10)Na3Ni2 square pyramids, corners with two equivalent O(2)Na3Ni2 square pyramids, corners with three equivalent O(6)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, edges with two equivalent O(3)Na2Ni3 square pyramids, and edges with two equivalent O(9)Na3Ni2 square pyramids. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Na(3), one Ni(1), and one Ni(3) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(3)Na2Ni3 square pyramids, corners with two equivalent O(2)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the sixth O site, O(6) is bonded to one Na(2), one Na(4), one Ni(1), one Ni(2), and one Ni(3) atom to form ONa2Ni3 square pyramids that share  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with three equivalent O(4)Na3Ni2 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, edges with two equivalent O(3)Na2Ni3 square pyramids, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Na(1), one Na(3), one Ni(3), and one Ni(4) atom. In the eighth O site, O(8) is bonded to one Na(3), one Na(4), one Ni(1), one Ni(2), and one Ni(4) atom to form ONa2Ni3 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(4)Na3Ni2 square pyramid, corners with two equivalent O(3)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid,  an edgeedge with one O(9)Na3Ni2 square pyramid, and  an edgeedge with one O(1)NaNi3 trigonal pyramid. In the ninth O site, O(9) is bonded to one Na(1), one Na(2), one Na(4), one Ni(3), and one Ni(4) atom to form ONa3Ni2 square pyramids that share  a cornercorner with one O(6)Na2Ni3 square pyramid,  a cornercorner with one O(10)Na3Ni2 square pyramid,  a cornercorner with one O(2)Na3Ni2 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid, corners with three equivalent O(3)Na2Ni3 square pyramids,  a cornercorner with one O(1)NaNi3 trigonal pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(10)Na3Ni2 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, and edges with two equivalent O(4)Na3Ni2 square pyramids. In the tenth O site, O(10) is bonded to one Na(1), one Na(2), one Na(3), one Ni(2), and one Ni(4) atom to form distorted ONa3Ni2 square pyramids that share  a cornercorner with one O(3)Na2Ni3 square pyramid,  a cornercorner with one O(8)Na2Ni3 square pyramid,  a cornercorner with one O(5)Na3Ni2 square pyramid,  a cornercorner with one O(9)Na3Ni2 square pyramid, corners with two equivalent O(4)Na3Ni2 square pyramids, corners with two equivalent O(1)NaNi3 trigonal pyramids,  an edgeedge with one O(3)Na2Ni3 square pyramid,  an edgeedge with one O(6)Na2Ni3 square pyramid,  an edgeedge with one O(8)Na2Ni3 square pyramid,  an edgeedge with one O(2)Na3Ni2 square pyramid,  an edgeedge with one O(4)Na3Ni2 square pyramid,  an edgeedge with one O(5)Na3Ni2 square pyramid, and  an edgeedge with one O(9)Na3Ni2 square pyramid. is represented by the CIF file [CIF]
data_Na2Ni2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.963
_cell_length_b   6.445
_cell_length_c   6.992
_cell_angle_alpha   110.719
_cell_angle_beta   95.785
_cell_angle_gamma   105.698
_symmetry_Int_Tables_number   1
_cell_volume   196.534
_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  0.200  0.392  0.407  1.0
  Na  Na1  1  0.564  0.694  0.204  1.0
  Na  Na2  1  0.847  0.109  0.601  1.0
  Na  Na3  1  0.982  0.499  0.011  1.0
  Ni  Ni4  1  0.402  0.805  0.801  1.0
  Ni  Ni5  1  0.998  0.997  0.996  1.0
  Ni  Ni6  1  0.802  0.602  0.601  1.0
  Ni  Ni7  1  0.596  0.199  0.197  1.0
  O  O8  1  0.097  0.906  0.727  1.0
  O  O9  1  0.103  0.521  0.711  1.0
  O  O10  1  0.302  0.892  0.071  1.0
  O  O11  1  0.293  0.286  0.093  1.0
  O  O12  1  0.529  0.741  0.550  1.0
  O  O13  1  0.703  0.694  0.872  1.0
  O  O14  1  0.564  0.286  0.477  1.0
  O  O15  1  0.701  0.108  0.925  1.0
  O  O16  1  0.844  0.512  0.319  1.0
  O  O17  1  0.866  0.055  0.245  1.0
[/CIF]
.