The crystal structure described by Ni7(PO4)6 crystallizes in the monoclinic Cm space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(13), one O(2), one O(3), one O(4), one O(5), and one O(9) atom to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one Ni(3)O6 octahedra, and  an edgeedge with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the second Ni site, Ni(2) is bonded to one O(10), one O(12), two equivalent O(11), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the third Ni site, Ni(3) is bonded to one O(1), one O(11), one O(3), one O(6), one O(7), and one O(9) atom to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Ni(1)O6 octahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the fourth Ni site, Ni(4) is bonded in a 6-coordinate geometry to one O(1), one O(13), one O(3), one O(5), one O(6), and one O(9) atom. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(11), one O(2), one O(6), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra, and  an edgeedge with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-55°. In the second P site, P(2) is bonded to one O(3), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra, and  an edgeedge with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-55°. In the third P site, P(3) is bonded to one O(10), one O(14), and two equivalent O(1) atoms to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra and corners with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-55°. In the fourth P site, P(4) is bonded to one O(12), one O(8), and two equivalent O(13) atoms to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra and corners with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ni(3), one Ni(4), and one P(3) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ni(1), one Ni(3), one Ni(4), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(2), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Ni(1), one Ni(4), and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Ni(3), one Ni(4), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Ni(3) and one P(2) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one P(4) atom. In the ninth O site, O(9) is bonded in a distorted rectangular see-saw-like geometry to one Ni(1), one Ni(3), one Ni(4), and one P(1) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Ni(2) and one P(3) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(3), and one P(1) atom. In the twelfth O site, O(12) is bonded in a distorted bent 150 degrees geometry to one Ni(2) and one P(4) atom. In the thirteenth O site, O(13) is bonded in a trigonal planar geometry to one Ni(1), one Ni(4), and one P(4) atom. In the fourteenth O site, O(14) is bonded in a single-bond geometry to one P(3) atom. is represented by the CIF file [CIF]
data_Ni7(PO4)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.800
_cell_length_b   8.800
_cell_length_c   6.572
_cell_angle_alpha   80.750
_cell_angle_beta   99.250
_cell_angle_gamma   71.962
_symmetry_Int_Tables_number   1
_cell_volume   465.393
_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
  Ni  Ni0  1  0.007  0.356  0.192  1.0
  Ni  Ni1  1  0.003  0.997  0.001  1.0
  Ni  Ni2  1  0.644  0.993  0.192  1.0
  Ni  Ni3  1  0.363  0.997  0.814  1.0
  Ni  Ni4  1  0.675  0.666  0.003  1.0
  Ni  Ni5  1  0.334  0.325  0.003  1.0
  Ni  Ni6  1  0.003  0.637  0.814  1.0
  P  P7  1  0.726  0.907  0.708  1.0
  P  P8  1  0.917  0.718  0.297  1.0
  P  P9  1  0.329  0.671  0.071  1.0
  P  P10  1  0.282  0.083  0.297  1.0
  P  P11  1  0.093  0.274  0.708  1.0
  P  P12  1  0.679  0.321  0.939  1.0
  O  O13  1  0.247  0.572  0.937  1.0
  O  O14  1  0.658  0.018  0.491  1.0
  O  O15  1  0.394  0.031  0.137  1.0
  O  O16  1  0.096  0.108  0.209  1.0
  O  O17  1  0.428  0.753  0.937  1.0
  O  O18  1  0.261  0.271  0.281  1.0
  O  O19  1  0.750  0.718  0.725  1.0
  O  O20  1  0.029  0.653  0.514  1.0
  O  O21  1  0.969  0.606  0.137  1.0
  O  O22  1  0.729  0.739  0.281  1.0
  O  O23  1  0.982  0.342  0.491  1.0
  O  O24  1  0.552  0.448  0.750  1.0
  O  O25  1  0.614  0.956  0.869  1.0
  O  O26  1  0.200  0.800  0.140  1.0
  O  O27  1  0.911  0.885  0.795  1.0
  O  O28  1  0.806  0.194  0.864  1.0
  O  O29  1  0.763  0.418  0.073  1.0
  O  O30  1  0.115  0.089  0.795  1.0
  O  O31  1  0.892  0.904  0.209  1.0
  O  O32  1  0.044  0.386  0.869  1.0
  O  O33  1  0.347  0.971  0.514  1.0
  O  O34  1  0.282  0.250  0.725  1.0
  O  O35  1  0.454  0.546  0.263  1.0
  O  O36  1  0.582  0.237  0.073  1.0
[/CIF]
.
The crystal structure described by Ni7(PO4)6 crystallizes in the monoclinic Cm space group. There are four inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(13), one O(2), one O(3), one O(4), one O(5), and one O(9) atom to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra,  an edgeedge with one Ni(3)O6 octahedra, and  an edgeedge with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the second Ni site, Ni(2) is bonded to one O(10), one O(12), two equivalent O(11), and two equivalent O(4) atoms to form NiO6 octahedra that share corners with two equivalent Ni(1)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra,  a cornercorner with one P(3)O4 tetrahedra,  a cornercorner with one P(4)O4 tetrahedra, corners with two equivalent P(1)O4 tetrahedra, and corners with two equivalent P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the third Ni site, Ni(3) is bonded to one O(1), one O(11), one O(3), one O(6), one O(7), and one O(9) atom to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra,  a cornercorner with one P(3)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra,  an edgeedge with one Ni(1)O6 octahedra, and  an edgeedge with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. In the fourth Ni site, Ni(4) is bonded in a 6-coordinate geometry to one O(1), one O(13), one O(3), one O(5), one O(6), and one O(9) atom. There are four inequivalent P sites. In the first P site, P(1) is bonded to one O(11), one O(2), one O(6), and one O(9) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra,  a cornercorner with one Ni(3)O6 octahedra, corners with two equivalent Ni(1)O6 octahedra, and  an edgeedge with one Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-55°. In the second P site, P(2) is bonded to one O(3), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one Ni(1)O6 octahedra,  a cornercorner with one Ni(2)O6 octahedra, corners with two equivalent Ni(3)O6 octahedra, and  an edgeedge with one Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-55°. In the third P site, P(3) is bonded to one O(10), one O(14), and two equivalent O(1) atoms to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra and corners with two equivalent Ni(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 43-55°. In the fourth P site, P(4) is bonded to one O(12), one O(8), and two equivalent O(13) atoms to form PO4 tetrahedra that share  a cornercorner with one Ni(2)O6 octahedra and corners with two equivalent Ni(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ni(3), one Ni(4), and one P(3) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Ni(1), one Ni(3), one Ni(4), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ni(1), one Ni(2), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Ni(1), one Ni(4), and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal non-coplanar geometry to one Ni(3), one Ni(4), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted bent 150 degrees geometry to one Ni(3) and one P(2) atom. In the eighth O site, O(8) is bonded in a single-bond geometry to one P(4) atom. In the ninth O site, O(9) is bonded in a distorted rectangular see-saw-like geometry to one Ni(1), one Ni(3), one Ni(4), and one P(1) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Ni(2) and one P(3) atom. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to one Ni(2), one Ni(3), and one P(1) atom. In the twelfth O site, O(12) is bonded in a distorted bent 150 degrees geometry to one Ni(2) and one P(4) atom. In the thirteenth O site, O(13) is bonded in a trigonal planar geometry to one Ni(1), one Ni(4), and one P(4) atom. In the fourteenth O site, O(14) is bonded in a single-bond geometry to one P(3) atom. is represented by the CIF file [CIF]
data_Ni7(PO4)6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.800
_cell_length_b   8.800
_cell_length_c   6.572
_cell_angle_alpha   80.750
_cell_angle_beta   99.250
_cell_angle_gamma   71.962
_symmetry_Int_Tables_number   1
_cell_volume   465.393
_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
  Ni  Ni0  1  0.007  0.356  0.192  1.0
  Ni  Ni1  1  0.003  0.997  0.001  1.0
  Ni  Ni2  1  0.644  0.993  0.192  1.0
  Ni  Ni3  1  0.363  0.997  0.814  1.0
  Ni  Ni4  1  0.675  0.666  0.003  1.0
  Ni  Ni5  1  0.334  0.325  0.003  1.0
  Ni  Ni6  1  0.003  0.637  0.814  1.0
  P  P7  1  0.726  0.907  0.708  1.0
  P  P8  1  0.917  0.718  0.297  1.0
  P  P9  1  0.329  0.671  0.071  1.0
  P  P10  1  0.282  0.083  0.297  1.0
  P  P11  1  0.093  0.274  0.708  1.0
  P  P12  1  0.679  0.321  0.939  1.0
  O  O13  1  0.247  0.572  0.937  1.0
  O  O14  1  0.658  0.018  0.491  1.0
  O  O15  1  0.394  0.031  0.137  1.0
  O  O16  1  0.096  0.108  0.209  1.0
  O  O17  1  0.428  0.753  0.937  1.0
  O  O18  1  0.261  0.271  0.281  1.0
  O  O19  1  0.750  0.718  0.725  1.0
  O  O20  1  0.029  0.653  0.514  1.0
  O  O21  1  0.969  0.606  0.137  1.0
  O  O22  1  0.729  0.739  0.281  1.0
  O  O23  1  0.982  0.342  0.491  1.0
  O  O24  1  0.552  0.448  0.750  1.0
  O  O25  1  0.614  0.956  0.869  1.0
  O  O26  1  0.200  0.800  0.140  1.0
  O  O27  1  0.911  0.885  0.795  1.0
  O  O28  1  0.806  0.194  0.864  1.0
  O  O29  1  0.763  0.418  0.073  1.0
  O  O30  1  0.115  0.089  0.795  1.0
  O  O31  1  0.892  0.904  0.209  1.0
  O  O32  1  0.044  0.386  0.869  1.0
  O  O33  1  0.347  0.971  0.514  1.0
  O  O34  1  0.282  0.250  0.725  1.0
  O  O35  1  0.454  0.546  0.263  1.0
  O  O36  1  0.582  0.237  0.073  1.0
[/CIF]
.