The compound described by NaNi3O8 crystallizes in the monoclinic Cm space group. Na(1) is bonded to one O(1), one O(2), two equivalent O(3), two equivalent O(4), and six equivalent O(5) atoms to form NaO12 cuboctahedra that share  a cornercorner with one Ni(1)O6 octahedra, corners with eight equivalent Ni(2)O6 octahedra, edges with six equivalent Na(1)O12 cuboctahedra,  an edgeedge with one Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-49°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form NiO6 octahedra that share  a cornercorner with one Na(1)O12 cuboctahedra,  an edgeedge with one Na(1)O12 cuboctahedra, edges with six equivalent Ni(2)O6 octahedra, and  a faceface with one Na(1)O12 cuboctahedra. In the second Ni site, Ni(2) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with four equivalent Na(1)O12 cuboctahedra,  an edgeedge with one Na(1)O12 cuboctahedra, edges with three equivalent Ni(1)O6 octahedra, and edges with three equivalent Ni(2)O6 octahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and two equivalent Ni(2) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and two equivalent Ni(2) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and two equivalent Ni(2) atoms. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and two equivalent Ni(2) atoms. In the fifth O site, O(5) is bonded in a trigonal planar geometry to three equivalent Na(1) atoms. is represented by the CIF file [CIF]
data_NaNi3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.809
_cell_length_b   4.809
_cell_length_c   7.056
_cell_angle_alpha   83.500
_cell_angle_beta   83.500
_cell_angle_gamma   119.991
_symmetry_Int_Tables_number   1
_cell_volume   137.650
_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  1.000  1.000  0.500  1.0
  Ni  Ni1  1  0.819  0.819  0.002  1.0
  Ni  Ni2  1  0.487  0.154  0.999  1.0
  Ni  Ni3  1  0.154  0.487  0.999  1.0
  O  O4  1  0.198  0.198  0.860  1.0
  O  O5  1  0.436  0.436  0.141  1.0
  O  O6  1  0.867  0.535  0.859  1.0
  O  O7  1  0.535  0.867  0.859  1.0
  O  O8  1  0.108  0.775  0.141  1.0
  O  O9  1  0.775  0.108  0.141  1.0
  O  O10  1  0.668  0.333  0.499  1.0
  O  O11  1  0.333  0.668  0.499  1.0
[/CIF]
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The compound described by NaNi3O8 crystallizes in the monoclinic Cm space group. Na(1) is bonded to one O(1), one O(2), two equivalent O(3), two equivalent O(4), and six equivalent O(5) atoms to form NaO12 cuboctahedra that share  a cornercorner with one Ni(1)O6 octahedra, corners with eight equivalent Ni(2)O6 octahedra, edges with six equivalent Na(1)O12 cuboctahedra,  an edgeedge with one Ni(1)O6 octahedra, edges with two equivalent Ni(2)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-49°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form NiO6 octahedra that share  a cornercorner with one Na(1)O12 cuboctahedra,  an edgeedge with one Na(1)O12 cuboctahedra, edges with six equivalent Ni(2)O6 octahedra, and  a faceface with one Na(1)O12 cuboctahedra. In the second Ni site, Ni(2) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with four equivalent Na(1)O12 cuboctahedra,  an edgeedge with one Na(1)O12 cuboctahedra, edges with three equivalent Ni(1)O6 octahedra, and edges with three equivalent Ni(2)O6 octahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and two equivalent Ni(2) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and two equivalent Ni(2) atoms. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and two equivalent Ni(2) atoms. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Na(1), one Ni(1), and two equivalent Ni(2) atoms. In the fifth O site, O(5) is bonded in a trigonal planar geometry to three equivalent Na(1) atoms. is represented by the CIF file [CIF]
data_NaNi3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.809
_cell_length_b   4.809
_cell_length_c   7.056
_cell_angle_alpha   83.500
_cell_angle_beta   83.500
_cell_angle_gamma   119.991
_symmetry_Int_Tables_number   1
_cell_volume   137.650
_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  1.000  1.000  0.500  1.0
  Ni  Ni1  1  0.819  0.819  0.002  1.0
  Ni  Ni2  1  0.487  0.154  0.999  1.0
  Ni  Ni3  1  0.154  0.487  0.999  1.0
  O  O4  1  0.198  0.198  0.860  1.0
  O  O5  1  0.436  0.436  0.141  1.0
  O  O6  1  0.867  0.535  0.859  1.0
  O  O7  1  0.535  0.867  0.859  1.0
  O  O8  1  0.108  0.775  0.141  1.0
  O  O9  1  0.775  0.108  0.141  1.0
  O  O10  1  0.668  0.333  0.499  1.0
  O  O11  1  0.333  0.668  0.499  1.0
[/CIF]
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