The compound described by Li2NiP2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(6), one O(7), and two equivalent O(4) atoms to form distorted LiO5 trigonal bipyramids that share corners with three equivalent Ni(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Ni(1)O6 octahedra, and  an edgeedge with one Li(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 59-71°. In the second Li site, Li(2) is bonded in a 4-coordinate geometry to one O(1), one O(3), one O(5), and one O(6) atom. 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, corners with three equivalent P(2)O4 tetrahedra, corners with three equivalent Li(1)O5 trigonal bipyramids, and  an edgeedge with one Li(1)O5 trigonal bipyramid. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  a cornercorner with one Li(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 32-51°. In the second P site, P(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with four equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 33-71°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Li(2), 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 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 4-coordinate geometry to two equivalent Li(1), one Ni(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Li(2), one P(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal pyramidal geometry to one Li(1), one Li(2), one Ni(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one Ni(1), and one P(1) atom. is represented by the CIF file [CIF]
data_Li2NiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.167
_cell_length_b   6.181
_cell_length_c   8.663
_cell_angle_alpha   71.539
_cell_angle_beta   87.115
_cell_angle_gamma   85.213
_symmetry_Int_Tables_number   1
_cell_volume   261.449
_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  0.793  0.209  0.459  1.0
  Li  Li1  1  0.207  0.791  0.541  1.0
  Li  Li2  1  0.705  0.057  0.843  1.0
  Li  Li3  1  0.296  0.943  0.157  1.0
  Ni  Ni4  1  0.759  0.563  0.734  1.0
  Ni  Ni5  1  0.241  0.437  0.267  1.0
  O  O6  1  0.932  0.795  0.821  1.0
  O  O7  1  0.068  0.205  0.179  1.0
  O  O8  1  0.892  0.540  0.339  1.0
  O  O9  1  0.108  0.460  0.661  1.0
  O  O10  1  0.740  0.293  0.948  1.0
  O  O11  1  0.260  0.707  0.052  1.0
  O  O12  1  0.788  0.838  0.483  1.0
  O  O13  1  0.213  0.162  0.517  1.0
  O  O14  1  0.734  0.934  0.169  1.0
  O  O15  1  0.266  0.066  0.830  1.0
  O  O16  1  0.582  0.303  0.640  1.0
  O  O17  1  0.418  0.697  0.360  1.0
  O  O18  1  0.590  0.289  0.239  1.0
  O  O19  1  0.410  0.711  0.761  1.0
  P  P20  1  0.786  0.207  0.130  1.0
  P  P21  1  0.214  0.793  0.870  1.0
  P  P22  1  0.711  0.739  0.351  1.0
  P  P23  1  0.289  0.261  0.649  1.0
[/CIF]
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The compound described by Li2NiP2O7 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(2), one O(6), one O(7), and two equivalent O(4) atoms to form distorted LiO5 trigonal bipyramids that share corners with three equivalent Ni(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, corners with four equivalent P(2)O4 tetrahedra,  an edgeedge with one Ni(1)O6 octahedra, and  an edgeedge with one Li(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 59-71°. In the second Li site, Li(2) is bonded in a 4-coordinate geometry to one O(1), one O(3), one O(5), and one O(6) atom. 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, corners with three equivalent P(2)O4 tetrahedra, corners with three equivalent Li(1)O5 trigonal bipyramids, and  an edgeedge with one Li(1)O5 trigonal bipyramid. There are two inequivalent P sites. In the first P site, P(1) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra,  a cornercorner with one P(2)O4 tetrahedra, and  a cornercorner with one Li(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 32-51°. In the second P site, P(2) is bonded to one O(2), one O(4), one O(5), and one O(6) atom to form PO4 tetrahedra that share corners with three equivalent Ni(1)O6 octahedra,  a cornercorner with one P(1)O4 tetrahedra, and corners with four equivalent Li(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 33-71°. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Li(2), 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 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 4-coordinate geometry to two equivalent Li(1), one Ni(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Li(2), one P(1), and one P(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal pyramidal geometry to one Li(1), one Li(2), one Ni(1), and one P(2) atom. In the seventh O site, O(7) is bonded in a distorted trigonal non-coplanar geometry to one Li(1), one Ni(1), and one P(1) atom. is represented by the CIF file [CIF]
data_Li2NiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.167
_cell_length_b   6.181
_cell_length_c   8.663
_cell_angle_alpha   71.539
_cell_angle_beta   87.115
_cell_angle_gamma   85.213
_symmetry_Int_Tables_number   1
_cell_volume   261.449
_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  0.793  0.209  0.459  1.0
  Li  Li1  1  0.207  0.791  0.541  1.0
  Li  Li2  1  0.705  0.057  0.843  1.0
  Li  Li3  1  0.296  0.943  0.157  1.0
  Ni  Ni4  1  0.759  0.563  0.734  1.0
  Ni  Ni5  1  0.241  0.437  0.267  1.0
  O  O6  1  0.932  0.795  0.821  1.0
  O  O7  1  0.068  0.205  0.179  1.0
  O  O8  1  0.892  0.540  0.339  1.0
  O  O9  1  0.108  0.460  0.661  1.0
  O  O10  1  0.740  0.293  0.948  1.0
  O  O11  1  0.260  0.707  0.052  1.0
  O  O12  1  0.788  0.838  0.483  1.0
  O  O13  1  0.213  0.162  0.517  1.0
  O  O14  1  0.734  0.934  0.169  1.0
  O  O15  1  0.266  0.066  0.830  1.0
  O  O16  1  0.582  0.303  0.640  1.0
  O  O17  1  0.418  0.697  0.360  1.0
  O  O18  1  0.590  0.289  0.239  1.0
  O  O19  1  0.410  0.711  0.761  1.0
  P  P20  1  0.786  0.207  0.130  1.0
  P  P21  1  0.214  0.793  0.870  1.0
  P  P22  1  0.711  0.739  0.351  1.0
  P  P23  1  0.289  0.261  0.649  1.0
[/CIF]
.