The structure described by Ni2(PO3)5 crystallizes in the monoclinic P2/c space group. Ni(1) is bonded to one O(2), one O(3), one O(4), one O(6), and one O(8) atom to form NiO5 square pyramids that share  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 square pyramids,  a cornercorner with one P(2)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. In the second P site, P(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 square pyramids,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(2)O4 tetrahedra. In the third P site, P(3) is bonded to two equivalent O(2) and two equivalent O(7) atoms to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 square pyramids and corners with two equivalent P(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Ni(1) and one P(2) atom. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to one P(1) and one P(2) atom. In the third O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ni(1) and one P(3) atom. In the fourth O site, O(3) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(1) atom. In the fifth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one P(2) atom. In the sixth O site, O(5) is bonded in a linear geometry to two equivalent P(2) atoms. In the seventh O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the eighth O site, O(7) is bonded in a bent 150 degrees geometry to one P(1) and one P(3) atom. is represented by the CIF file [CIF]
data_Ni2(PO3)5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.637
_cell_length_b   5.341
_cell_length_c   13.525
_cell_angle_alpha   70.708
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   588.825
_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
  Ni  Ni0  1  0.281  0.892  0.454  1.0
  Ni  Ni1  1  0.719  0.108  0.546  1.0
  Ni  Ni2  1  0.281  0.108  0.046  1.0
  Ni  Ni3  1  0.719  0.892  0.954  1.0
  P  P4  1  0.178  0.298  0.590  1.0
  P  P5  1  0.512  0.540  0.360  1.0
  P  P6  1  0.488  0.540  0.860  1.0
  P  P7  1  0.056  0.000  0.250  1.0
  P  P8  1  0.822  0.298  0.090  1.0
  P  P9  1  0.178  0.702  0.910  1.0
  P  P10  1  0.488  0.460  0.640  1.0
  P  P11  1  0.512  0.460  0.140  1.0
  P  P12  1  0.944  0.000  0.750  1.0
  P  P13  1  0.822  0.702  0.410  1.0
  O  O14  1  0.342  0.273  0.649  1.0
  O  O15  1  0.145  0.910  0.172  1.0
  O  O16  1  0.175  0.092  0.538  1.0
  O  O17  1  0.368  0.307  0.135  1.0
  O  O18  1  0.489  0.500  0.750  1.0
  O  O19  1  0.342  0.727  0.851  1.0
  O  O20  1  0.368  0.693  0.365  1.0
  O  O21  1  0.854  0.581  0.026  1.0
  O  O22  1  0.145  0.090  0.328  1.0
  O  O23  1  0.632  0.693  0.865  1.0
  O  O24  1  0.825  0.092  0.038  1.0
  O  O25  1  0.059  0.763  0.812  1.0
  O  O26  1  0.658  0.727  0.351  1.0
  O  O27  1  0.632  0.307  0.635  1.0
  O  O28  1  0.855  0.090  0.828  1.0
  O  O29  1  0.059  0.237  0.688  1.0
  O  O30  1  0.146  0.581  0.526  1.0
  O  O31  1  0.175  0.908  0.962  1.0
  O  O32  1  0.511  0.500  0.250  1.0
  O  O33  1  0.533  0.732  0.058  1.0
  O  O34  1  0.825  0.908  0.462  1.0
  O  O35  1  0.533  0.268  0.442  1.0
  O  O36  1  0.854  0.419  0.474  1.0
  O  O37  1  0.467  0.268  0.942  1.0
  O  O38  1  0.467  0.732  0.558  1.0
  O  O39  1  0.146  0.419  0.974  1.0
  O  O40  1  0.941  0.763  0.312  1.0
  O  O41  1  0.658  0.273  0.149  1.0
  O  O42  1  0.855  0.910  0.672  1.0
  O  O43  1  0.941  0.237  0.188  1.0
[/CIF]
.
The structure described by Ni2(PO3)5 crystallizes in the monoclinic P2/c space group. Ni(1) is bonded to one O(2), one O(3), one O(4), one O(6), and one O(8) atom to form NiO5 square pyramids that share  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. There are three inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(6), and one O(7) atom to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 square pyramids,  a cornercorner with one P(2)O4 tetrahedra, and  a cornercorner with one P(3)O4 tetrahedra. In the second P site, P(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 square pyramids,  a cornercorner with one P(1)O4 tetrahedra, and  a cornercorner with one P(2)O4 tetrahedra. In the third P site, P(3) is bonded to two equivalent O(2) and two equivalent O(7) atoms to form PO4 tetrahedra that share corners with two equivalent Ni(1)O5 square pyramids and corners with two equivalent P(1)O4 tetrahedra. There are eight inequivalent O sites. In the first O site, O(8) is bonded in a distorted bent 120 degrees geometry to one Ni(1) and one P(2) atom. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to one P(1) and one P(2) atom. In the third O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ni(1) and one P(3) atom. In the fourth O site, O(3) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(1) atom. In the fifth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one P(2) atom. In the sixth O site, O(5) is bonded in a linear geometry to two equivalent P(2) atoms. In the seventh O site, O(6) is bonded in a distorted bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the eighth O site, O(7) is bonded in a bent 150 degrees geometry to one P(1) and one P(3) atom. is represented by the CIF file [CIF]
data_Ni2(PO3)5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.637
_cell_length_b   5.341
_cell_length_c   13.525
_cell_angle_alpha   70.708
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   588.825
_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
  Ni  Ni0  1  0.281  0.892  0.454  1.0
  Ni  Ni1  1  0.719  0.108  0.546  1.0
  Ni  Ni2  1  0.281  0.108  0.046  1.0
  Ni  Ni3  1  0.719  0.892  0.954  1.0
  P  P4  1  0.178  0.298  0.590  1.0
  P  P5  1  0.512  0.540  0.360  1.0
  P  P6  1  0.488  0.540  0.860  1.0
  P  P7  1  0.056  0.000  0.250  1.0
  P  P8  1  0.822  0.298  0.090  1.0
  P  P9  1  0.178  0.702  0.910  1.0
  P  P10  1  0.488  0.460  0.640  1.0
  P  P11  1  0.512  0.460  0.140  1.0
  P  P12  1  0.944  0.000  0.750  1.0
  P  P13  1  0.822  0.702  0.410  1.0
  O  O14  1  0.342  0.273  0.649  1.0
  O  O15  1  0.145  0.910  0.172  1.0
  O  O16  1  0.175  0.092  0.538  1.0
  O  O17  1  0.368  0.307  0.135  1.0
  O  O18  1  0.489  0.500  0.750  1.0
  O  O19  1  0.342  0.727  0.851  1.0
  O  O20  1  0.368  0.693  0.365  1.0
  O  O21  1  0.854  0.581  0.026  1.0
  O  O22  1  0.145  0.090  0.328  1.0
  O  O23  1  0.632  0.693  0.865  1.0
  O  O24  1  0.825  0.092  0.038  1.0
  O  O25  1  0.059  0.763  0.812  1.0
  O  O26  1  0.658  0.727  0.351  1.0
  O  O27  1  0.632  0.307  0.635  1.0
  O  O28  1  0.855  0.090  0.828  1.0
  O  O29  1  0.059  0.237  0.688  1.0
  O  O30  1  0.146  0.581  0.526  1.0
  O  O31  1  0.175  0.908  0.962  1.0
  O  O32  1  0.511  0.500  0.250  1.0
  O  O33  1  0.533  0.732  0.058  1.0
  O  O34  1  0.825  0.908  0.462  1.0
  O  O35  1  0.533  0.268  0.442  1.0
  O  O36  1  0.854  0.419  0.474  1.0
  O  O37  1  0.467  0.268  0.942  1.0
  O  O38  1  0.467  0.732  0.558  1.0
  O  O39  1  0.146  0.419  0.974  1.0
  O  O40  1  0.941  0.763  0.312  1.0
  O  O41  1  0.658  0.273  0.149  1.0
  O  O42  1  0.855  0.910  0.672  1.0
  O  O43  1  0.941  0.237  0.188  1.0
[/CIF]
.