The material described by NaNi(AsO4) crystallizes in the trigonal R-3 space group. Na(1) is bonded in a 7-coordinate geometry to three equivalent O(2) and four equivalent O(1) atoms. Ni(1) is bonded to six equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent As(1)O4 tetrahedra and edges with three equivalent Ni(1)O6 octahedra. As(1) is bonded to one O(1) and three equivalent O(2) atoms to form AsO4 tetrahedra that share corners with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-57°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to four equivalent Na(1) and one As(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Ni(1), and one As(1) atom. is represented by the CIF file [CIF]
data_NaNiAsO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.026
_cell_length_b   5.026
_cell_length_c   9.359
_cell_angle_alpha   74.425
_cell_angle_beta   74.424
_cell_angle_gamma   60.001
_symmetry_Int_Tables_number   1
_cell_volume   194.647
_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
  As  As0  1  0.566  0.566  0.302  1.0
  As  As1  1  0.434  0.434  0.698  1.0
  Na  Na2  1  0.287  0.287  0.138  1.0
  Na  Na3  1  0.713  0.713  0.862  1.0
  Ni  Ni4  1  0.164  0.164  0.507  1.0
  Ni  Ni5  1  0.836  0.836  0.493  1.0
  O  O6  1  0.629  0.629  0.113  1.0
  O  O7  1  0.371  0.371  0.887  1.0
  O  O8  1  0.536  0.221  0.363  1.0
  O  O9  1  0.464  0.779  0.637  1.0
  O  O10  1  0.880  0.536  0.363  1.0
  O  O11  1  0.221  0.880  0.363  1.0
  O  O12  1  0.779  0.120  0.637  1.0
  O  O13  1  0.120  0.464  0.637  1.0
[/CIF]
.
The material described by NaNi(AsO4) crystallizes in the trigonal R-3 space group. Na(1) is bonded in a 7-coordinate geometry to three equivalent O(2) and four equivalent O(1) atoms. Ni(1) is bonded to six equivalent O(2) atoms to form NiO6 octahedra that share corners with six equivalent As(1)O4 tetrahedra and edges with three equivalent Ni(1)O6 octahedra. As(1) is bonded to one O(1) and three equivalent O(2) atoms to form AsO4 tetrahedra that share corners with six equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 53-57°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to four equivalent Na(1) and one As(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Ni(1), and one As(1) atom. is represented by the CIF file [CIF]
data_NaNiAsO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.026
_cell_length_b   5.026
_cell_length_c   9.359
_cell_angle_alpha   74.425
_cell_angle_beta   74.424
_cell_angle_gamma   60.001
_symmetry_Int_Tables_number   1
_cell_volume   194.647
_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
  As  As0  1  0.566  0.566  0.302  1.0
  As  As1  1  0.434  0.434  0.698  1.0
  Na  Na2  1  0.287  0.287  0.138  1.0
  Na  Na3  1  0.713  0.713  0.862  1.0
  Ni  Ni4  1  0.164  0.164  0.507  1.0
  Ni  Ni5  1  0.836  0.836  0.493  1.0
  O  O6  1  0.629  0.629  0.113  1.0
  O  O7  1  0.371  0.371  0.887  1.0
  O  O8  1  0.536  0.221  0.363  1.0
  O  O9  1  0.464  0.779  0.637  1.0
  O  O10  1  0.880  0.536  0.363  1.0
  O  O11  1  0.221  0.880  0.363  1.0
  O  O12  1  0.779  0.120  0.637  1.0
  O  O13  1  0.120  0.464  0.637  1.0
[/CIF]
.