The material described by LiNiPO4 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(4), one O(6), and one O(7) atom. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(5) atom to form distorted NiO5 trigonal bipyramids that share  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. In the second Ni site, Ni(2) is bonded in a rectangular see-saw-like geometry to one O(4), one O(6), one O(7), and one O(8) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 trigonal bipyramids and  an edgeedge with one Ni(1)O5 trigonal bipyramid. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O5 trigonal bipyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(1), one Ni(1), and one P(1) atom. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Ni(1), and one P(1) atom to form distorted corner-sharing OLi2NiP tetrahedra. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Li(2), one Ni(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Ni(1), one Ni(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(2), one Ni(1), and one P(2) atom. In the sixth O site, O(6) is bonded to one Li(1), one Li(2), one Ni(2), and one P(2) atom to form a mixture of distorted edge and corner-sharing OLi2NiP trigonal pyramids. In the seventh O site, O(7) is bonded to one Li(1), one Li(2), one Ni(2), and one P(2) atom to form a mixture of distorted edge and corner-sharing OLi2NiP tetrahedra. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Li(2), one Ni(2), and one P(2) atom. is represented by the CIF file [CIF]
data_LiNiPO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.796
_cell_length_b   4.710
_cell_length_c   6.695
_cell_angle_alpha   89.654
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   308.889
_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
  Li  Li0  1  0.305  0.757  0.736  1.0
  Li  Li1  1  0.742  0.294  0.724  1.0
  Li  Li2  1  0.242  0.706  0.276  1.0
  Li  Li3  1  0.805  0.243  0.264  1.0
  Ni  Ni4  1  0.015  0.784  0.967  1.0
  Ni  Ni5  1  0.088  0.241  0.533  1.0
  Ni  Ni6  1  0.588  0.759  0.467  1.0
  Ni  Ni7  1  0.515  0.216  0.033  1.0
  P  P8  1  0.200  0.207  0.976  1.0
  P  P9  1  0.906  0.723  0.530  1.0
  P  P10  1  0.406  0.277  0.470  1.0
  P  P11  1  0.700  0.793  0.024  1.0
  O  O12  1  0.344  0.091  0.923  1.0
  O  O13  1  0.191  0.535  0.976  1.0
  O  O14  1  0.639  0.933  0.833  1.0
  O  O15  1  0.108  0.078  0.801  1.0
  O  O16  1  0.909  0.610  0.749  1.0
  O  O17  1  0.275  0.413  0.561  1.0
  O  O18  1  0.900  0.052  0.512  1.0
  O  O19  1  0.536  0.388  0.580  1.0
  O  O20  1  0.036  0.612  0.420  1.0
  O  O21  1  0.400  0.948  0.488  1.0
  O  O22  1  0.775  0.587  0.439  1.0
  O  O23  1  0.409  0.390  0.251  1.0
  O  O24  1  0.608  0.922  0.199  1.0
  O  O25  1  0.139  0.067  0.167  1.0
  O  O26  1  0.691  0.465  0.024  1.0
  O  O27  1  0.844  0.909  0.077  1.0
[/CIF]
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The material described by LiNiPO4 crystallizes in the monoclinic P2_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(4), one O(6), and one O(7) atom. In the second Li site, Li(2) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(5), one O(6), one O(7), and one O(8) atom. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(2), one O(3), one O(4), and one O(5) atom to form distorted NiO5 trigonal bipyramids that share  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and  an edgeedge with one P(1)O4 tetrahedra. In the second Ni site, Ni(2) is bonded in a rectangular see-saw-like geometry to one O(4), one O(6), one O(7), and one O(8) atom. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 trigonal bipyramids and  an edgeedge with one Ni(1)O5 trigonal bipyramid. In the second P site, P(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O5 trigonal bipyramid. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Li(1), one Ni(1), and one P(1) atom. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Ni(1), and one P(1) atom to form distorted corner-sharing OLi2NiP tetrahedra. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Li(2), one Ni(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one Ni(1), one Ni(2), and one P(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(2), one Ni(1), and one P(2) atom. In the sixth O site, O(6) is bonded to one Li(1), one Li(2), one Ni(2), and one P(2) atom to form a mixture of distorted edge and corner-sharing OLi2NiP trigonal pyramids. In the seventh O site, O(7) is bonded to one Li(1), one Li(2), one Ni(2), and one P(2) atom to form a mixture of distorted edge and corner-sharing OLi2NiP tetrahedra. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Li(2), one Ni(2), and one P(2) atom. is represented by the CIF file [CIF]
data_LiNiPO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.796
_cell_length_b   4.710
_cell_length_c   6.695
_cell_angle_alpha   89.654
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   308.889
_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
  Li  Li0  1  0.305  0.757  0.736  1.0
  Li  Li1  1  0.742  0.294  0.724  1.0
  Li  Li2  1  0.242  0.706  0.276  1.0
  Li  Li3  1  0.805  0.243  0.264  1.0
  Ni  Ni4  1  0.015  0.784  0.967  1.0
  Ni  Ni5  1  0.088  0.241  0.533  1.0
  Ni  Ni6  1  0.588  0.759  0.467  1.0
  Ni  Ni7  1  0.515  0.216  0.033  1.0
  P  P8  1  0.200  0.207  0.976  1.0
  P  P9  1  0.906  0.723  0.530  1.0
  P  P10  1  0.406  0.277  0.470  1.0
  P  P11  1  0.700  0.793  0.024  1.0
  O  O12  1  0.344  0.091  0.923  1.0
  O  O13  1  0.191  0.535  0.976  1.0
  O  O14  1  0.639  0.933  0.833  1.0
  O  O15  1  0.108  0.078  0.801  1.0
  O  O16  1  0.909  0.610  0.749  1.0
  O  O17  1  0.275  0.413  0.561  1.0
  O  O18  1  0.900  0.052  0.512  1.0
  O  O19  1  0.536  0.388  0.580  1.0
  O  O20  1  0.036  0.612  0.420  1.0
  O  O21  1  0.400  0.948  0.488  1.0
  O  O22  1  0.775  0.587  0.439  1.0
  O  O23  1  0.409  0.390  0.251  1.0
  O  O24  1  0.608  0.922  0.199  1.0
  O  O25  1  0.139  0.067  0.167  1.0
  O  O26  1  0.691  0.465  0.024  1.0
  O  O27  1  0.844  0.909  0.077  1.0
[/CIF]
.