The crystal structure described by NaNiPO4 is Ilmenite-derived structured and crystallizes in the orthorhombic Pnma space group. Na(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted NaO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, corners with four equivalent Ni(1)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-67°. Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-66°. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-68°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), two equivalent Ni(1), and one P(1) atom to form distorted corner-sharing ONaNi2P trigonal pyramids. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Ni(1), and one P(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ni(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaNiPO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.689
_cell_length_b   11.382
_cell_length_c   6.458
_cell_angle_alpha   90.005
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   344.668
_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  0.477  0.222  0.750  1.0
  Na  Na1  1  0.977  0.278  0.250  1.0
  Na  Na2  1  0.023  0.722  0.750  1.0
  Na  Na3  1  0.523  0.778  0.250  1.0
  Ni  Ni4  1  0.000  0.000  0.500  1.0
  Ni  Ni5  1  0.500  0.500  0.500  1.0
  Ni  Ni6  1  0.000  0.000  1.000  1.0
  Ni  Ni7  1  0.500  0.500  0.000  1.0
  P  P8  1  0.405  0.079  0.250  1.0
  P  P9  1  0.905  0.421  0.750  1.0
  P  P10  1  0.095  0.579  0.250  1.0
  P  P11  1  0.595  0.921  0.750  1.0
  O  O12  1  0.745  0.046  0.750  1.0
  O  O13  1  0.245  0.454  0.250  1.0
  O  O14  1  0.755  0.546  0.750  1.0
  O  O15  1  0.255  0.954  0.250  1.0
  O  O16  1  0.736  0.072  0.250  1.0
  O  O17  1  0.236  0.428  0.750  1.0
  O  O18  1  0.764  0.572  0.250  1.0
  O  O19  1  0.264  0.928  0.750  1.0
  O  O20  1  0.287  0.140  0.448  1.0
  O  O21  1  0.287  0.140  0.052  1.0
  O  O22  1  0.787  0.360  0.948  1.0
  O  O23  1  0.787  0.360  0.552  1.0
  O  O24  1  0.213  0.640  0.052  1.0
  O  O25  1  0.213  0.640  0.448  1.0
  O  O26  1  0.713  0.860  0.552  1.0
  O  O27  1  0.713  0.860  0.948  1.0
[/CIF]
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The crystal structure described by NaNiPO4 is Ilmenite-derived structured and crystallizes in the orthorhombic Pnma space group. Na(1) is bonded to one O(1), one O(2), and four equivalent O(3) atoms to form distorted NaO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, corners with four equivalent Ni(1)O6 octahedra, corners with four equivalent P(1)O4 tetrahedra, edges with two equivalent Ni(1)O6 octahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-67°. Ni(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form NiO6 octahedra that share corners with four equivalent Na(1)O6 octahedra, corners with two equivalent P(1)O4 tetrahedra, edges with two equivalent Na(1)O6 octahedra, edges with two equivalent Ni(1)O6 octahedra, and edges with two equivalent P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-66°. P(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form PO4 tetrahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with four equivalent Na(1)O6 octahedra,  an edgeedge with one Na(1)O6 octahedra, and edges with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-68°. There are three inequivalent O sites. In the first O site, O(1) is bonded to one Na(1), two equivalent Ni(1), and one P(1) atom to form distorted corner-sharing ONaNi2P trigonal pyramids. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), two equivalent Ni(1), and one P(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ni(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_NaNiPO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.689
_cell_length_b   11.382
_cell_length_c   6.458
_cell_angle_alpha   90.005
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   344.668
_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  0.477  0.222  0.750  1.0
  Na  Na1  1  0.977  0.278  0.250  1.0
  Na  Na2  1  0.023  0.722  0.750  1.0
  Na  Na3  1  0.523  0.778  0.250  1.0
  Ni  Ni4  1  0.000  0.000  0.500  1.0
  Ni  Ni5  1  0.500  0.500  0.500  1.0
  Ni  Ni6  1  0.000  0.000  1.000  1.0
  Ni  Ni7  1  0.500  0.500  0.000  1.0
  P  P8  1  0.405  0.079  0.250  1.0
  P  P9  1  0.905  0.421  0.750  1.0
  P  P10  1  0.095  0.579  0.250  1.0
  P  P11  1  0.595  0.921  0.750  1.0
  O  O12  1  0.745  0.046  0.750  1.0
  O  O13  1  0.245  0.454  0.250  1.0
  O  O14  1  0.755  0.546  0.750  1.0
  O  O15  1  0.255  0.954  0.250  1.0
  O  O16  1  0.736  0.072  0.250  1.0
  O  O17  1  0.236  0.428  0.750  1.0
  O  O18  1  0.764  0.572  0.250  1.0
  O  O19  1  0.264  0.928  0.750  1.0
  O  O20  1  0.287  0.140  0.448  1.0
  O  O21  1  0.287  0.140  0.052  1.0
  O  O22  1  0.787  0.360  0.948  1.0
  O  O23  1  0.787  0.360  0.552  1.0
  O  O24  1  0.213  0.640  0.052  1.0
  O  O25  1  0.213  0.640  0.448  1.0
  O  O26  1  0.713  0.860  0.552  1.0
  O  O27  1  0.713  0.860  0.948  1.0
[/CIF]
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