The compound described by LiNiP2O7 crystallizes in the triclinic P-1 space group. Li(1) is bonded in a 5-coordinate geometry to one O(2), one O(6), one O(7), and two equivalent O(3) atoms. Ni(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form NiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 17-48°. In the second P site, P(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-66°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Ni(1), and one P(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Li(1), one Ni(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Ni(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Li(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 Li(1), one Ni(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiNiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.129
_cell_length_b   6.130
_cell_length_c   8.687
_cell_angle_alpha   70.654
_cell_angle_beta   88.377
_cell_angle_gamma   86.767
_symmetry_Int_Tables_number   1
_cell_volume   257.289
_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
  Li  Li0  1  0.775  0.189  0.477  1.0
  Li  Li1  1  0.225  0.811  0.523  1.0
  Ni  Ni2  1  0.768  0.560  0.730  1.0
  Ni  Ni3  1  0.232  0.440  0.270  1.0
  P  P4  1  0.787  0.200  0.133  1.0
  P  P5  1  0.694  0.735  0.342  1.0
  P  P6  1  0.306  0.265  0.658  1.0
  P  P7  1  0.213  0.800  0.867  1.0
  O  O8  1  0.945  0.801  0.794  1.0
  O  O9  1  0.877  0.529  0.342  1.0
  O  O10  1  0.768  0.829  0.479  1.0
  O  O11  1  0.771  0.319  0.952  1.0
  O  O12  1  0.735  0.931  0.166  1.0
  O  O13  1  0.593  0.324  0.645  1.0
  O  O14  1  0.580  0.284  0.235  1.0
  O  O15  1  0.420  0.716  0.765  1.0
  O  O16  1  0.407  0.676  0.355  1.0
  O  O17  1  0.265  0.069  0.834  1.0
  O  O18  1  0.229  0.681  0.048  1.0
  O  O19  1  0.232  0.171  0.521  1.0
  O  O20  1  0.123  0.471  0.658  1.0
  O  O21  1  0.055  0.199  0.206  1.0
[/CIF]
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The compound described by LiNiP2O7 crystallizes in the triclinic P-1 space group. Li(1) is bonded in a 5-coordinate geometry to one O(2), one O(6), one O(7), and two equivalent O(3) atoms. Ni(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form NiO6 octahedra that share corners with three equivalent P(1)O4 tetrahedra and corners with three equivalent P(2)O4 tetrahedra. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(4), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and  a cornercorner with one P(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 17-48°. In the second P site, P(2) is bonded to one O(2), one O(3), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra and  a cornercorner with one P(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 36-66°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ni(1) and one P(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Li(1), one Ni(1), and one P(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Li(1), one Ni(1), and one P(2) atom. In the fourth O site, O(4) is bonded in a distorted linear geometry to one Ni(1) and one P(1) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Li(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 Li(1), one Ni(1), and one P(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiNiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.129
_cell_length_b   6.130
_cell_length_c   8.687
_cell_angle_alpha   70.654
_cell_angle_beta   88.377
_cell_angle_gamma   86.767
_symmetry_Int_Tables_number   1
_cell_volume   257.289
_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
  Li  Li0  1  0.775  0.189  0.477  1.0
  Li  Li1  1  0.225  0.811  0.523  1.0
  Ni  Ni2  1  0.768  0.560  0.730  1.0
  Ni  Ni3  1  0.232  0.440  0.270  1.0
  P  P4  1  0.787  0.200  0.133  1.0
  P  P5  1  0.694  0.735  0.342  1.0
  P  P6  1  0.306  0.265  0.658  1.0
  P  P7  1  0.213  0.800  0.867  1.0
  O  O8  1  0.945  0.801  0.794  1.0
  O  O9  1  0.877  0.529  0.342  1.0
  O  O10  1  0.768  0.829  0.479  1.0
  O  O11  1  0.771  0.319  0.952  1.0
  O  O12  1  0.735  0.931  0.166  1.0
  O  O13  1  0.593  0.324  0.645  1.0
  O  O14  1  0.580  0.284  0.235  1.0
  O  O15  1  0.420  0.716  0.765  1.0
  O  O16  1  0.407  0.676  0.355  1.0
  O  O17  1  0.265  0.069  0.834  1.0
  O  O18  1  0.229  0.681  0.048  1.0
  O  O19  1  0.232  0.171  0.521  1.0
  O  O20  1  0.123  0.471  0.658  1.0
  O  O21  1  0.055  0.199  0.206  1.0
[/CIF]
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