The crystal structure described by Na3NiN2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal I4_1/amd space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 2-coordinate geometry to two equivalent N(1) atoms. In the second Na site, Na(2) is bonded to four equivalent N(1) atoms to form a mixture of distorted edge and corner-sharing NaN4 tetrahedra. Ni(1) is bonded in a linear geometry to two equivalent N(1) atoms. N(1) is bonded in a 6-coordinate geometry to one Na(1), four equivalent Na(2), and one Ni(1) atom. is represented by the CIF card [CIF]
data_Na3NiN2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.443
_cell_length_b   7.993
_cell_length_c   12.544
_cell_angle_alpha   90.000
_cell_angle_beta   137.975
_cell_angle_gamma   118.254
_symmetry_Int_Tables_number   1
_cell_volume   400.718
_cell_formula_units_Z   4
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  0.000  0.500  0.366  1.0
  Na  Na1  1  0.000  0.000  0.884  1.0
  Na  Na2  1  0.000  0.500  0.134  1.0
  Na  Na3  1  0.000  0.000  0.116  1.0
  Na  Na4  1  0.582  0.500  0.541  1.0
  Na  Na5  1  0.418  0.500  0.959  1.0
  Na  Na6  1  0.582  0.000  0.291  1.0
  Na  Na7  1  0.418  0.000  0.709  1.0
  Na  Na8  1  0.418  0.918  0.959  1.0
  Na  Na9  1  0.582  0.082  0.541  1.0
  Na  Na10  1  0.418  0.418  0.709  1.0
  Na  Na11  1  0.582  0.582  0.291  1.0
  Ni  Ni12  1  0.000  0.500  0.591  1.0
  Ni  Ni13  1  0.000  0.000  0.659  1.0
  Ni  Ni14  1  0.000  0.500  0.909  1.0
  Ni  Ni15  1  0.000  0.000  0.341  1.0
  N  N16  1  0.423  0.711  0.797  1.0
  N  N17  1  0.577  0.289  0.374  1.0
  N  N18  1  0.423  0.211  0.876  1.0
  N  N19  1  0.577  0.789  0.453  1.0
  N  N20  1  0.000  0.289  0.914  1.0
  N  N21  1  0.000  0.711  0.914  1.0
  N  N22  1  0.000  0.789  0.336  1.0
  N  N23  1  0.000  0.211  0.336  1.0
[/CIF]
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The crystal structure described by Na3NiN2 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the tetragonal I4_1/amd space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 2-coordinate geometry to two equivalent N(1) atoms. In the second Na site, Na(2) is bonded to four equivalent N(1) atoms to form a mixture of distorted edge and corner-sharing NaN4 tetrahedra. Ni(1) is bonded in a linear geometry to two equivalent N(1) atoms. N(1) is bonded in a 6-coordinate geometry to one Na(1), four equivalent Na(2), and one Ni(1) atom. is represented by the CIF card [CIF]
data_Na3NiN2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.443
_cell_length_b   7.993
_cell_length_c   12.544
_cell_angle_alpha   90.000
_cell_angle_beta   137.975
_cell_angle_gamma   118.254
_symmetry_Int_Tables_number   1
_cell_volume   400.718
_cell_formula_units_Z   4
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  0.000  0.500  0.366  1.0
  Na  Na1  1  0.000  0.000  0.884  1.0
  Na  Na2  1  0.000  0.500  0.134  1.0
  Na  Na3  1  0.000  0.000  0.116  1.0
  Na  Na4  1  0.582  0.500  0.541  1.0
  Na  Na5  1  0.418  0.500  0.959  1.0
  Na  Na6  1  0.582  0.000  0.291  1.0
  Na  Na7  1  0.418  0.000  0.709  1.0
  Na  Na8  1  0.418  0.918  0.959  1.0
  Na  Na9  1  0.582  0.082  0.541  1.0
  Na  Na10  1  0.418  0.418  0.709  1.0
  Na  Na11  1  0.582  0.582  0.291  1.0
  Ni  Ni12  1  0.000  0.500  0.591  1.0
  Ni  Ni13  1  0.000  0.000  0.659  1.0
  Ni  Ni14  1  0.000  0.500  0.909  1.0
  Ni  Ni15  1  0.000  0.000  0.341  1.0
  N  N16  1  0.423  0.711  0.797  1.0
  N  N17  1  0.577  0.289  0.374  1.0
  N  N18  1  0.423  0.211  0.876  1.0
  N  N19  1  0.577  0.789  0.453  1.0
  N  N20  1  0.000  0.289  0.914  1.0
  N  N21  1  0.000  0.711  0.914  1.0
  N  N22  1  0.000  0.789  0.336  1.0
  N  N23  1  0.000  0.211  0.336  1.0
[/CIF]
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