The compound described by Ni2P2O7 crystallizes in the monoclinic C2/m space group. Ni(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form distorted NiO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra and edges with three equivalent Ni(1)O6 octahedra. 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 six equivalent Ni(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-62°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent P(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(1) atom. is represented by the CIF file [CIF]
data_Ni2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.451
_cell_length_b   5.208
_cell_length_c   5.208
_cell_angle_alpha   104.168
_cell_angle_beta   97.750
_cell_angle_gamma   97.750
_symmetry_Int_Tables_number   1
_cell_volume   114.192
_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  0.500  0.313  0.687  1.0
  Ni  Ni1  1  0.500  0.687  0.313  1.0
  O  O2  1  0.000  1.000  0.000  1.0
  O  O3  1  0.218  0.380  0.380  1.0
  O  O4  1  0.782  0.620  0.620  1.0
  O  O5  1  0.277  0.924  0.615  1.0
  O  O6  1  0.723  0.385  0.076  1.0
  O  O7  1  0.723  0.076  0.385  1.0
  O  O8  1  0.277  0.615  0.924  1.0
  P  P9  1  0.908  0.221  0.221  1.0
  P  P10  1  0.092  0.779  0.779  1.0
[/CIF]
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The compound described by Ni2P2O7 crystallizes in the monoclinic C2/m space group. Ni(1) is bonded to two equivalent O(2) and four equivalent O(3) atoms to form distorted NiO6 octahedra that share corners with six equivalent P(1)O4 tetrahedra and edges with three equivalent Ni(1)O6 octahedra. 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 six equivalent Ni(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 47-62°. There are three inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent P(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(1) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to two equivalent Ni(1) and one P(1) atom. is represented by the CIF file [CIF]
data_Ni2P2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.451
_cell_length_b   5.208
_cell_length_c   5.208
_cell_angle_alpha   104.168
_cell_angle_beta   97.750
_cell_angle_gamma   97.750
_symmetry_Int_Tables_number   1
_cell_volume   114.192
_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  0.500  0.313  0.687  1.0
  Ni  Ni1  1  0.500  0.687  0.313  1.0
  O  O2  1  0.000  1.000  0.000  1.0
  O  O3  1  0.218  0.380  0.380  1.0
  O  O4  1  0.782  0.620  0.620  1.0
  O  O5  1  0.277  0.924  0.615  1.0
  O  O6  1  0.723  0.385  0.076  1.0
  O  O7  1  0.723  0.076  0.385  1.0
  O  O8  1  0.277  0.615  0.924  1.0
  P  P9  1  0.908  0.221  0.221  1.0
  P  P10  1  0.092  0.779  0.779  1.0
[/CIF]
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