The material structure described by Na9Ni7O16 is Caswellsilverite-like structured and crystallizes in the triclinic P-1 space group. There are five inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(8) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Ni(1)O6 octahedra, corners with two equivalent Ni(2)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-21°. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(7), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, corners with two equivalent Ni(2)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-18°. In the third Na site, Na(3) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(7) atoms to form NaO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-16°. In the fourth Na site, Na(4) is bonded to one O(2), one O(3), one O(5), one O(8), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-19°. In the fifth Na site, Na(5) is bonded to two equivalent O(1), two equivalent O(6), and two equivalent O(8) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 18-21°. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(5), one O(6), one O(7), one O(8), and two equivalent O(3) atoms to form NiO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Na(4)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-16°. In the second Ni site, Ni(2) is bonded to one O(1), one O(4), one O(7), one O(8), and two equivalent O(2) atoms to form NiO6 octahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra, corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-16°. In the third Ni site, Ni(3) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form NiO6 octahedra that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra, corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(3)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-14°. In the fourth Ni site, Ni(4) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(7) atoms to form NiO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-16°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Na(2), one Na(3), one Na(5), one Ni(2), and one Ni(3) atom to form distorted ONa4Ni2 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(3)Na3Ni3 octahedra,  an edgeedge with one O(5)Na3Ni3 octahedra, edges with two equivalent O(2)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(7)Na3Ni3 octahedra, edges with two equivalent O(6)Na4Ni2 octahedra, and edges with two equivalent O(8)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the second O site, O(2) is bonded to one Na(2), one Na(3), one Na(4), one Ni(3), and two equivalent Ni(2) atoms to form ONa3Ni3 octahedra that share  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(2)Na3Ni3 octahedra,  an edgeedge with one O(3)Na3Ni3 octahedra,  an edgeedge with one O(5)Na3Ni3 octahedra,  an edgeedge with one O(8)Na4Ni2 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(7)Na3Ni3 octahedra, edges with two equivalent O(1)Na4Ni2 octahedra, and edges with two equivalent O(6)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 1-8°. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Na(4), one Ni(3), and two equivalent Ni(1) atoms to form ONa3Ni3 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(2)Na3Ni3 octahedra,  an edgeedge with one O(3)Na3Ni3 octahedra,  an edgeedge with one O(7)Na3Ni3 octahedra,  an edgeedge with one O(1)Na4Ni2 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with two equivalent O(6)Na4Ni2 octahedra, and edges with two equivalent O(8)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 2-10°. In the fourth O site, O(4) is bonded to one Na(1), two equivalent Na(2), one Ni(2), one Ni(3), and one Ni(4) atom to form distorted ONa3Ni3 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(4)Na3Ni3 octahedra,  an edgeedge with one O(8)Na4Ni2 octahedra, edges with two equivalent O(2)Na3Ni3 octahedra, edges with two equivalent O(3)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with two equivalent O(7)Na3Ni3 octahedra, and edges with two equivalent O(1)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the fifth O site, O(5) is bonded to one Na(1), one Na(3), one Na(4), one Ni(1), one Ni(3), and one Ni(4) atom to form ONa3Ni3 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  an edgeedge with one O(2)Na3Ni3 octahedra,  an edgeedge with one O(1)Na4Ni2 octahedra, edges with two equivalent O(3)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(7)Na3Ni3 octahedra, edges with two equivalent O(6)Na4Ni2 octahedra, and edges with two equivalent O(8)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the sixth O site, O(6) is bonded to one Na(3), one Na(5), two equivalent Na(4), one Ni(1), and one Ni(3) atom to form distorted ONa4Ni2 octahedra that share  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(7)Na3Ni3 octahedra,  an edgeedge with one O(6)Na4Ni2 octahedra, edges with two equivalent O(2)Na3Ni3 octahedra, edges with two equivalent O(3)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with two equivalent O(1)Na4Ni2 octahedra, and edges with two equivalent O(8)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the seventh O site, O(7) is bonded to one Na(2), two equivalent Na(3), one Ni(1), one Ni(2), and one Ni(4) atom to form ONa3Ni3 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  an edgeedge with one O(3)Na3Ni3 octahedra,  an edgeedge with one O(7)Na3Ni3 octahedra,  an edgeedge with one O(6)Na4Ni2 octahedra,  an edgeedge with one O(8)Na4Ni2 octahedra, edges with two equivalent O(2)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, and edges with two equivalent O(1)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the eighth O site, O(8) is bonded to one Na(4), one Na(5), two equivalent Na(1), one Ni(1), and one Ni(2) atom to form distorted ONa4Ni2 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(2)Na3Ni3 octahedra,  an edgeedge with one O(4)Na3Ni3 octahedra,  an edgeedge with one O(7)Na3Ni3 octahedra,  an edgeedge with one O(8)Na4Ni2 octahedra, edges with two equivalent O(3)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with two equivalent O(1)Na4Ni2 octahedra, and edges with two equivalent O(6)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. is represented by the CIF file [CIF]
data_Na9Ni7O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.900
_cell_length_b   6.976
_cell_length_c   7.924
_cell_angle_alpha   65.658
_cell_angle_beta   77.040
_cell_angle_gamma   69.492
_symmetry_Int_Tables_number   1
_cell_volume   324.082
_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  0.423  0.561  0.812  1.0
  Na  Na1  1  0.314  0.685  0.432  1.0
  Na  Na2  1  0.686  0.315  0.568  1.0
  Na  Na3  1  0.054  0.929  0.691  1.0
  Na  Na4  1  0.186  0.797  0.067  1.0
  Na  Na5  1  0.577  0.439  0.188  1.0
  Na  Na6  1  0.000  0.500  0.000  1.0
  Na  Na7  1  0.946  0.071  0.309  1.0
  Na  Na8  1  0.814  0.203  0.933  1.0
  Ni  Ni9  1  0.621  0.882  0.870  1.0
  Ni  Ni10  1  0.873  0.633  0.618  1.0
  Ni  Ni11  1  0.252  0.244  0.749  1.0
  Ni  Ni12  1  0.748  0.756  0.251  1.0
  Ni  Ni13  1  0.127  0.367  0.382  1.0
  Ni  Ni14  1  0.500  0.000  0.500  1.0
  Ni  Ni15  1  0.379  0.118  0.130  1.0
  O  O16  1  0.142  0.553  0.709  1.0
  O  O17  1  0.007  0.296  0.641  1.0
  O  O18  1  0.503  0.191  0.848  1.0
  O  O19  1  0.993  0.704  0.359  1.0
  O  O20  1  0.624  0.692  0.506  1.0
  O  O21  1  0.497  0.809  0.152  1.0
  O  O22  1  0.365  0.940  0.771  1.0
  O  O23  1  0.376  0.308  0.494  1.0
  O  O24  1  0.856  0.845  0.992  1.0
  O  O25  1  0.858  0.447  0.291  1.0
  O  O26  1  0.748  0.963  0.590  1.0
  O  O27  1  0.252  0.037  0.410  1.0
  O  O28  1  0.635  0.060  0.229  1.0
  O  O29  1  0.719  0.587  0.863  1.0
  O  O30  1  0.281  0.413  0.137  1.0
  O  O31  1  0.144  0.155  0.008  1.0
[/CIF]
.
The material structure described by Na9Ni7O16 is Caswellsilverite-like structured and crystallizes in the triclinic P-1 space group. There are five inequivalent Na sites. In the first Na site, Na(1) is bonded to one O(1), one O(3), one O(4), one O(5), and two equivalent O(8) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Ni(1)O6 octahedra, corners with two equivalent Ni(2)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-21°. In the second Na site, Na(2) is bonded to one O(1), one O(2), one O(3), one O(7), and two equivalent O(4) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, corners with two equivalent Ni(2)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 12-18°. In the third Na site, Na(3) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(7) atoms to form NaO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(3)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-16°. In the fourth Na site, Na(4) is bonded to one O(2), one O(3), one O(5), one O(8), and two equivalent O(6) atoms to form distorted NaO6 octahedra that share  a cornercorner with one Na(5)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra,  a cornercorner with one Ni(4)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-19°. In the fifth Na site, Na(5) is bonded to two equivalent O(1), two equivalent O(6), and two equivalent O(8) atoms to form NaO6 octahedra that share corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 18-21°. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(5), one O(6), one O(7), one O(8), and two equivalent O(3) atoms to form NiO6 octahedra that share  a cornercorner with one Na(1)O6 octahedra,  a cornercorner with one Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Na(4)O6 octahedra,  an edgeedge with one Na(2)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-16°. In the second Ni site, Ni(2) is bonded to one O(1), one O(4), one O(7), one O(8), and two equivalent O(2) atoms to form NiO6 octahedra that share  a cornercorner with one Na(3)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra, corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(2)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(4)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(1)O6 octahedra,  an edgeedge with one Ni(2)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 11-16°. In the third Ni site, Ni(3) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form NiO6 octahedra that share  a cornercorner with one Na(2)O6 octahedra,  a cornercorner with one Na(4)O6 octahedra, corners with two equivalent Na(1)O6 octahedra, corners with two equivalent Na(3)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra,  an edgeedge with one Na(3)O6 octahedra,  an edgeedge with one Na(5)O6 octahedra,  an edgeedge with one Ni(4)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(4)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent Ni(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 10-14°. In the fourth Ni site, Ni(4) is bonded to two equivalent O(4), two equivalent O(5), and two equivalent O(7) atoms to form NiO6 octahedra that share corners with two equivalent Na(2)O6 octahedra, corners with two equivalent Na(3)O6 octahedra, corners with two equivalent Na(4)O6 octahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Na(2)O6 octahedra, edges with two equivalent Na(3)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and edges with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-16°. There are eight inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), one Na(2), one Na(3), one Na(5), one Ni(2), and one Ni(3) atom to form distorted ONa4Ni2 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(3)Na3Ni3 octahedra,  an edgeedge with one O(5)Na3Ni3 octahedra, edges with two equivalent O(2)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(7)Na3Ni3 octahedra, edges with two equivalent O(6)Na4Ni2 octahedra, and edges with two equivalent O(8)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the second O site, O(2) is bonded to one Na(2), one Na(3), one Na(4), one Ni(3), and two equivalent Ni(2) atoms to form ONa3Ni3 octahedra that share  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(2)Na3Ni3 octahedra,  an edgeedge with one O(3)Na3Ni3 octahedra,  an edgeedge with one O(5)Na3Ni3 octahedra,  an edgeedge with one O(8)Na4Ni2 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(7)Na3Ni3 octahedra, edges with two equivalent O(1)Na4Ni2 octahedra, and edges with two equivalent O(6)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 1-8°. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Na(4), one Ni(3), and two equivalent Ni(1) atoms to form ONa3Ni3 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(2)Na3Ni3 octahedra,  an edgeedge with one O(3)Na3Ni3 octahedra,  an edgeedge with one O(7)Na3Ni3 octahedra,  an edgeedge with one O(1)Na4Ni2 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with two equivalent O(6)Na4Ni2 octahedra, and edges with two equivalent O(8)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 2-10°. In the fourth O site, O(4) is bonded to one Na(1), two equivalent Na(2), one Ni(2), one Ni(3), and one Ni(4) atom to form distorted ONa3Ni3 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(4)Na3Ni3 octahedra,  an edgeedge with one O(8)Na4Ni2 octahedra, edges with two equivalent O(2)Na3Ni3 octahedra, edges with two equivalent O(3)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with two equivalent O(7)Na3Ni3 octahedra, and edges with two equivalent O(1)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the fifth O site, O(5) is bonded to one Na(1), one Na(3), one Na(4), one Ni(1), one Ni(3), and one Ni(4) atom to form ONa3Ni3 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  an edgeedge with one O(2)Na3Ni3 octahedra,  an edgeedge with one O(1)Na4Ni2 octahedra, edges with two equivalent O(3)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(7)Na3Ni3 octahedra, edges with two equivalent O(6)Na4Ni2 octahedra, and edges with two equivalent O(8)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-8°. In the sixth O site, O(6) is bonded to one Na(3), one Na(5), two equivalent Na(4), one Ni(1), and one Ni(3) atom to form distorted ONa4Ni2 octahedra that share  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(7)Na3Ni3 octahedra,  an edgeedge with one O(6)Na4Ni2 octahedra, edges with two equivalent O(2)Na3Ni3 octahedra, edges with two equivalent O(3)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with two equivalent O(1)Na4Ni2 octahedra, and edges with two equivalent O(8)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. In the seventh O site, O(7) is bonded to one Na(2), two equivalent Na(3), one Ni(1), one Ni(2), and one Ni(4) atom to form ONa3Ni3 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(5)Na3Ni3 octahedra,  a cornercorner with one O(7)Na3Ni3 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  an edgeedge with one O(3)Na3Ni3 octahedra,  an edgeedge with one O(7)Na3Ni3 octahedra,  an edgeedge with one O(6)Na4Ni2 octahedra,  an edgeedge with one O(8)Na4Ni2 octahedra, edges with two equivalent O(2)Na3Ni3 octahedra, edges with two equivalent O(4)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, and edges with two equivalent O(1)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the eighth O site, O(8) is bonded to one Na(4), one Na(5), two equivalent Na(1), one Ni(1), and one Ni(2) atom to form distorted ONa4Ni2 octahedra that share  a cornercorner with one O(2)Na3Ni3 octahedra,  a cornercorner with one O(3)Na3Ni3 octahedra,  a cornercorner with one O(4)Na3Ni3 octahedra,  a cornercorner with one O(1)Na4Ni2 octahedra,  a cornercorner with one O(6)Na4Ni2 octahedra,  a cornercorner with one O(8)Na4Ni2 octahedra,  an edgeedge with one O(2)Na3Ni3 octahedra,  an edgeedge with one O(4)Na3Ni3 octahedra,  an edgeedge with one O(7)Na3Ni3 octahedra,  an edgeedge with one O(8)Na4Ni2 octahedra, edges with two equivalent O(3)Na3Ni3 octahedra, edges with two equivalent O(5)Na3Ni3 octahedra, edges with two equivalent O(1)Na4Ni2 octahedra, and edges with two equivalent O(6)Na4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-10°. is represented by the CIF file [CIF]
data_Na9Ni7O16
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.900
_cell_length_b   6.976
_cell_length_c   7.924
_cell_angle_alpha   65.658
_cell_angle_beta   77.040
_cell_angle_gamma   69.492
_symmetry_Int_Tables_number   1
_cell_volume   324.082
_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  0.423  0.561  0.812  1.0
  Na  Na1  1  0.314  0.685  0.432  1.0
  Na  Na2  1  0.686  0.315  0.568  1.0
  Na  Na3  1  0.054  0.929  0.691  1.0
  Na  Na4  1  0.186  0.797  0.067  1.0
  Na  Na5  1  0.577  0.439  0.188  1.0
  Na  Na6  1  0.000  0.500  0.000  1.0
  Na  Na7  1  0.946  0.071  0.309  1.0
  Na  Na8  1  0.814  0.203  0.933  1.0
  Ni  Ni9  1  0.621  0.882  0.870  1.0
  Ni  Ni10  1  0.873  0.633  0.618  1.0
  Ni  Ni11  1  0.252  0.244  0.749  1.0
  Ni  Ni12  1  0.748  0.756  0.251  1.0
  Ni  Ni13  1  0.127  0.367  0.382  1.0
  Ni  Ni14  1  0.500  0.000  0.500  1.0
  Ni  Ni15  1  0.379  0.118  0.130  1.0
  O  O16  1  0.142  0.553  0.709  1.0
  O  O17  1  0.007  0.296  0.641  1.0
  O  O18  1  0.503  0.191  0.848  1.0
  O  O19  1  0.993  0.704  0.359  1.0
  O  O20  1  0.624  0.692  0.506  1.0
  O  O21  1  0.497  0.809  0.152  1.0
  O  O22  1  0.365  0.940  0.771  1.0
  O  O23  1  0.376  0.308  0.494  1.0
  O  O24  1  0.856  0.845  0.992  1.0
  O  O25  1  0.858  0.447  0.291  1.0
  O  O26  1  0.748  0.963  0.590  1.0
  O  O27  1  0.252  0.037  0.410  1.0
  O  O28  1  0.635  0.060  0.229  1.0
  O  O29  1  0.719  0.587  0.863  1.0
  O  O30  1  0.281  0.413  0.137  1.0
  O  O31  1  0.144  0.155  0.008  1.0
[/CIF]
.