The material structure described by Na3NiF6 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to two equivalent F(1), two equivalent F(3), and three equivalent F(2) atoms. In the second Na site, Na(2) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form NaF6 octahedra that share corners with six equivalent Ni(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 31-41°. Ni(1) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form NiF6 octahedra that share corners with six equivalent Na(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 31-41°. There are three inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), and one Ni(1) atom. In the second F site, F(2) is bonded in a 5-coordinate geometry to one Na(2), three equivalent Na(1), and one Ni(1) atom. In the third F site, F(3) is bonded in a distorted see-saw-like geometry to one Na(2), two equivalent Na(1), and one Ni(1) atom. is represented by the CIF file [CIF]
data_Na3NiF6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.702
_cell_length_b   5.360
_cell_length_c   9.264
_cell_angle_alpha   55.848
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   234.301
_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  0.564  0.720  0.256  1.0
  Na  Na1  1  0.064  0.280  0.244  1.0
  Na  Na2  1  0.436  0.280  0.744  1.0
  Na  Na3  1  0.936  0.720  0.756  1.0
  Na  Na4  1  0.500  0.500  0.000  1.0
  Na  Na5  1  0.000  0.500  0.500  1.0
  Ni  Ni6  1  0.500  0.000  0.500  1.0
  Ni  Ni7  1  0.000  0.000  0.000  1.0
  F  F8  1  0.217  0.742  0.579  1.0
  F  F9  1  0.717  0.258  0.921  1.0
  F  F10  1  0.783  0.258  0.421  1.0
  F  F11  1  0.283  0.742  0.079  1.0
  F  F12  1  0.326  0.321  0.456  1.0
  F  F13  1  0.826  0.679  0.044  1.0
  F  F14  1  0.674  0.679  0.544  1.0
  F  F15  1  0.174  0.321  0.956  1.0
  F  F16  1  0.056  0.103  0.779  1.0
  F  F17  1  0.556  0.897  0.721  1.0
  F  F18  1  0.944  0.897  0.221  1.0
  F  F19  1  0.444  0.103  0.279  1.0
[/CIF]
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The material structure described by Na3NiF6 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to two equivalent F(1), two equivalent F(3), and three equivalent F(2) atoms. In the second Na site, Na(2) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form NaF6 octahedra that share corners with six equivalent Ni(1)F6 octahedra. The corner-sharing octahedral tilt angles range from 31-41°. Ni(1) is bonded to two equivalent F(1), two equivalent F(2), and two equivalent F(3) atoms to form NiF6 octahedra that share corners with six equivalent Na(2)F6 octahedra. The corner-sharing octahedral tilt angles range from 31-41°. There are three inequivalent F sites. In the first F site, F(1) is bonded in a 4-coordinate geometry to one Na(2), two equivalent Na(1), and one Ni(1) atom. In the second F site, F(2) is bonded in a 5-coordinate geometry to one Na(2), three equivalent Na(1), and one Ni(1) atom. In the third F site, F(3) is bonded in a distorted see-saw-like geometry to one Na(2), two equivalent Na(1), and one Ni(1) atom. is represented by the CIF file [CIF]
data_Na3NiF6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.702
_cell_length_b   5.360
_cell_length_c   9.264
_cell_angle_alpha   55.848
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   234.301
_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  0.564  0.720  0.256  1.0
  Na  Na1  1  0.064  0.280  0.244  1.0
  Na  Na2  1  0.436  0.280  0.744  1.0
  Na  Na3  1  0.936  0.720  0.756  1.0
  Na  Na4  1  0.500  0.500  0.000  1.0
  Na  Na5  1  0.000  0.500  0.500  1.0
  Ni  Ni6  1  0.500  0.000  0.500  1.0
  Ni  Ni7  1  0.000  0.000  0.000  1.0
  F  F8  1  0.217  0.742  0.579  1.0
  F  F9  1  0.717  0.258  0.921  1.0
  F  F10  1  0.783  0.258  0.421  1.0
  F  F11  1  0.283  0.742  0.079  1.0
  F  F12  1  0.326  0.321  0.456  1.0
  F  F13  1  0.826  0.679  0.044  1.0
  F  F14  1  0.674  0.679  0.544  1.0
  F  F15  1  0.174  0.321  0.956  1.0
  F  F16  1  0.056  0.103  0.779  1.0
  F  F17  1  0.556  0.897  0.721  1.0
  F  F18  1  0.944  0.897  0.221  1.0
  F  F19  1  0.444  0.103  0.279  1.0
[/CIF]
.