The structure described by Ti5Ni(PO4)6 crystallizes in the trigonal R3 space group. There are five inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a faceface with one Ti(3)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. In the second Ti site, Ti(2) is bonded to three equivalent O(4) and three equivalent O(7) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a faceface with one Ti(4)O6 octahedra, and  a faceface with one Ti(5)O6 octahedra. In the third Ti site, Ti(3) is bonded to three equivalent O(2) and three equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. In the fourth Ti site, Ti(4) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(2)O6 octahedra. In the fifth Ti site, Ti(5) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(2)O6 octahedra. Ni(1) is bonded to three equivalent O(3) and three equivalent O(6) atoms to form distorted NiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(4)O6 octahedra,  a cornercorner with one Ti(5)O6 octahedra, and  a cornercorner with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-50°. In the second P site, P(2) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(4)O6 octahedra,  a cornercorner with one Ti(5)O6 octahedra, and  a cornercorner with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-55°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ti(4) and one P(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ti(1), one Ti(3), and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ti(2), one Ti(4), and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ti(3) and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Ti(1), one Ni(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ti(2), one Ti(5), and one P(2) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Ti(5) and one P(1) atom. is represented by the CIF file [CIF]
data_Ti5Ni(PO4)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.248
_cell_length_b   8.248
_cell_length_c   8.248
_cell_angle_alpha   63.599
_cell_angle_beta   63.599
_cell_angle_gamma   63.599
_symmetry_Int_Tables_number   1
_cell_volume   428.242
_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
  Ti  Ti0  1  0.003  0.003  0.003  1.0
  Ti  Ti1  1  0.501  0.501  0.501  1.0
  Ti  Ti2  1  0.137  0.137  0.137  1.0
  Ti  Ti3  1  0.359  0.359  0.359  1.0
  Ti  Ti4  1  0.638  0.638  0.638  1.0
  Ni  Ni5  1  0.860  0.860  0.860  1.0
  P  P6  1  0.464  0.748  0.043  1.0
  P  P7  1  0.748  0.043  0.464  1.0
  P  P8  1  0.958  0.545  0.244  1.0
  P  P9  1  0.244  0.958  0.545  1.0
  P  P10  1  0.545  0.244  0.958  1.0
  P  P11  1  0.043  0.464  0.748  1.0
  O  O12  1  0.490  0.328  0.113  1.0
  O  O13  1  0.113  0.490  0.328  1.0
  O  O14  1  0.260  0.896  0.056  1.0
  O  O15  1  0.328  0.113  0.490  1.0
  O  O16  1  0.613  0.820  0.014  1.0
  O  O17  1  0.440  0.595  0.246  1.0
  O  O18  1  0.896  0.056  0.260  1.0
  O  O19  1  0.595  0.246  0.440  1.0
  O  O20  1  0.996  0.391  0.170  1.0
  O  O21  1  0.246  0.440  0.595  1.0
  O  O22  1  0.950  0.745  0.102  1.0
  O  O23  1  0.170  0.996  0.391  1.0
  O  O24  1  0.820  0.014  0.613  1.0
  O  O25  1  0.056  0.260  0.896  1.0
  O  O26  1  0.757  0.558  0.397  1.0
  O  O27  1  0.014  0.613  0.820  1.0
  O  O28  1  0.397  0.757  0.558  1.0
  O  O29  1  0.102  0.950  0.745  1.0
  O  O30  1  0.558  0.397  0.757  1.0
  O  O31  1  0.391  0.170  0.996  1.0
  O  O32  1  0.670  0.888  0.506  1.0
  O  O33  1  0.745  0.102  0.950  1.0
  O  O34  1  0.888  0.506  0.670  1.0
  O  O35  1  0.506  0.670  0.888  1.0
[/CIF]
.
The structure described by Ti5Ni(PO4)6 crystallizes in the trigonal R3 space group. There are five inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to three equivalent O(2) and three equivalent O(6) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a faceface with one Ti(3)O6 octahedra, and  a faceface with one Ni(1)O6 octahedra. In the second Ti site, Ti(2) is bonded to three equivalent O(4) and three equivalent O(7) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra,  a faceface with one Ti(4)O6 octahedra, and  a faceface with one Ti(5)O6 octahedra. In the third Ti site, Ti(3) is bonded to three equivalent O(2) and three equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. In the fourth Ti site, Ti(4) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(2)O6 octahedra. In the fifth Ti site, Ti(5) is bonded to three equivalent O(7) and three equivalent O(8) atoms to form TiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(2)O6 octahedra. Ni(1) is bonded to three equivalent O(3) and three equivalent O(6) atoms to form distorted NiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra, corners with three equivalent P(2)O4 tetrahedra, and  a faceface with one Ti(1)O6 octahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(2), one O(3), one O(4), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(4)O6 octahedra,  a cornercorner with one Ti(5)O6 octahedra, and  a cornercorner with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 27-50°. In the second P site, P(2) is bonded to one O(1), one O(5), one O(6), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra,  a cornercorner with one Ti(4)O6 octahedra,  a cornercorner with one Ti(5)O6 octahedra, and  a cornercorner with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 25-55°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ti(4) and one P(2) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ti(1), one Ti(3), and one P(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ti(2), one Ti(4), and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ti(3) and one P(2) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Ti(1), one Ni(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one Ti(2), one Ti(5), and one P(2) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Ti(5) and one P(1) atom. is represented by the CIF file [CIF]
data_Ti5Ni(PO4)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.248
_cell_length_b   8.248
_cell_length_c   8.248
_cell_angle_alpha   63.599
_cell_angle_beta   63.599
_cell_angle_gamma   63.599
_symmetry_Int_Tables_number   1
_cell_volume   428.242
_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
  Ti  Ti0  1  0.003  0.003  0.003  1.0
  Ti  Ti1  1  0.501  0.501  0.501  1.0
  Ti  Ti2  1  0.137  0.137  0.137  1.0
  Ti  Ti3  1  0.359  0.359  0.359  1.0
  Ti  Ti4  1  0.638  0.638  0.638  1.0
  Ni  Ni5  1  0.860  0.860  0.860  1.0
  P  P6  1  0.464  0.748  0.043  1.0
  P  P7  1  0.748  0.043  0.464  1.0
  P  P8  1  0.958  0.545  0.244  1.0
  P  P9  1  0.244  0.958  0.545  1.0
  P  P10  1  0.545  0.244  0.958  1.0
  P  P11  1  0.043  0.464  0.748  1.0
  O  O12  1  0.490  0.328  0.113  1.0
  O  O13  1  0.113  0.490  0.328  1.0
  O  O14  1  0.260  0.896  0.056  1.0
  O  O15  1  0.328  0.113  0.490  1.0
  O  O16  1  0.613  0.820  0.014  1.0
  O  O17  1  0.440  0.595  0.246  1.0
  O  O18  1  0.896  0.056  0.260  1.0
  O  O19  1  0.595  0.246  0.440  1.0
  O  O20  1  0.996  0.391  0.170  1.0
  O  O21  1  0.246  0.440  0.595  1.0
  O  O22  1  0.950  0.745  0.102  1.0
  O  O23  1  0.170  0.996  0.391  1.0
  O  O24  1  0.820  0.014  0.613  1.0
  O  O25  1  0.056  0.260  0.896  1.0
  O  O26  1  0.757  0.558  0.397  1.0
  O  O27  1  0.014  0.613  0.820  1.0
  O  O28  1  0.397  0.757  0.558  1.0
  O  O29  1  0.102  0.950  0.745  1.0
  O  O30  1  0.558  0.397  0.757  1.0
  O  O31  1  0.391  0.170  0.996  1.0
  O  O32  1  0.670  0.888  0.506  1.0
  O  O33  1  0.745  0.102  0.950  1.0
  O  O34  1  0.888  0.506  0.670  1.0
  O  O35  1  0.506  0.670  0.888  1.0
[/CIF]
.