The structure 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(3), one O(4), and one O(5) atom to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(2)O4 trigonal pyramids. In the second Li site, Li(2) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(1)O4 trigonal pyramids. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a square co-planar geometry to two equivalent O(4) and two equivalent O(5) atoms. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to two equivalent O(6) and two equivalent O(7) atoms. 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(6) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent Li(1)O4 trigonal pyramids, and corners with two equivalent Li(2)O4 trigonal pyramids. In the second P site, P(2) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent Li(1)O4 trigonal pyramids, and corners with two equivalent Li(2)O4 trigonal pyramids. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one P(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(1), one Ni(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Ni(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Li(2), one Ni(2), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(2), one Ni(2), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2NiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.704
_cell_length_b   7.030
_cell_length_c   8.110
_cell_angle_alpha   64.388
_cell_angle_beta   65.736
_cell_angle_gamma   89.893
_symmetry_Int_Tables_number   1
_cell_volume   306.924
_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  0.770  0.770  0.460  1.0
  Li  Li1  1  0.229  0.730  0.540  1.0
  Li  Li2  1  0.771  0.270  0.460  1.0
  Li  Li3  1  0.230  0.230  0.540  1.0
  Ni  Ni4  1  0.000  0.000  1.000  1.0
  Ni  Ni5  1  1.000  0.500  0.000  1.0
  O  O6  1  0.434  0.749  0.001  1.0
  O  O7  1  0.566  0.251  0.999  1.0
  O  O8  1  0.718  0.445  0.612  1.0
  O  O9  1  0.666  0.943  0.613  1.0
  O  O10  1  0.282  0.555  0.388  1.0
  O  O11  1  0.334  0.057  0.387  1.0
  O  O12  1  0.075  0.818  0.224  1.0
  O  O13  1  0.703  0.957  0.222  1.0
  O  O14  1  0.295  0.681  0.778  1.0
  O  O15  1  0.923  0.543  0.778  1.0
  O  O16  1  0.077  0.457  0.223  1.0
  O  O17  1  0.704  0.319  0.222  1.0
  O  O18  1  0.925  0.182  0.776  1.0
  O  O19  1  0.297  0.043  0.778  1.0
  P  P20  1  0.428  0.860  0.780  1.0
  P  P21  1  0.791  0.361  0.779  1.0
  P  P22  1  0.209  0.639  0.221  1.0
  P  P23  1  0.572  0.140  0.219  1.0
[/CIF]
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The structure 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(3), one O(4), and one O(5) atom to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(2)O4 trigonal pyramids. In the second Li site, Li(2) is bonded to one O(2), one O(3), one O(6), and one O(7) atom to form distorted LiO4 trigonal pyramids that share corners with two equivalent P(1)O4 tetrahedra, corners with two equivalent P(2)O4 tetrahedra, and corners with two equivalent Li(1)O4 trigonal pyramids. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a square co-planar geometry to two equivalent O(4) and two equivalent O(5) atoms. In the second Ni site, Ni(2) is bonded in a square co-planar geometry to two equivalent O(6) and two equivalent O(7) atoms. 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(6) atom to form PO4 tetrahedra that share  a cornercorner with one P(2)O4 tetrahedra, corners with two equivalent Li(1)O4 trigonal pyramids, and corners with two equivalent Li(2)O4 trigonal pyramids. In the second P site, P(2) is bonded to one O(1), one O(2), one O(4), and one O(7) atom to form PO4 tetrahedra that share  a cornercorner with one P(1)O4 tetrahedra, corners with two equivalent Li(1)O4 trigonal pyramids, and corners with two equivalent Li(2)O4 trigonal pyramids. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a bent 120 degrees geometry to one P(1) and one P(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one P(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Li(1), one Li(2), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Li(1), one Ni(1), and one P(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Ni(1), and one P(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Li(2), one Ni(2), and one P(1) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Li(2), one Ni(2), and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2NiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.704
_cell_length_b   7.030
_cell_length_c   8.110
_cell_angle_alpha   64.388
_cell_angle_beta   65.736
_cell_angle_gamma   89.893
_symmetry_Int_Tables_number   1
_cell_volume   306.924
_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  0.770  0.770  0.460  1.0
  Li  Li1  1  0.229  0.730  0.540  1.0
  Li  Li2  1  0.771  0.270  0.460  1.0
  Li  Li3  1  0.230  0.230  0.540  1.0
  Ni  Ni4  1  0.000  0.000  1.000  1.0
  Ni  Ni5  1  1.000  0.500  0.000  1.0
  O  O6  1  0.434  0.749  0.001  1.0
  O  O7  1  0.566  0.251  0.999  1.0
  O  O8  1  0.718  0.445  0.612  1.0
  O  O9  1  0.666  0.943  0.613  1.0
  O  O10  1  0.282  0.555  0.388  1.0
  O  O11  1  0.334  0.057  0.387  1.0
  O  O12  1  0.075  0.818  0.224  1.0
  O  O13  1  0.703  0.957  0.222  1.0
  O  O14  1  0.295  0.681  0.778  1.0
  O  O15  1  0.923  0.543  0.778  1.0
  O  O16  1  0.077  0.457  0.223  1.0
  O  O17  1  0.704  0.319  0.222  1.0
  O  O18  1  0.925  0.182  0.776  1.0
  O  O19  1  0.297  0.043  0.778  1.0
  P  P20  1  0.428  0.860  0.780  1.0
  P  P21  1  0.791  0.361  0.779  1.0
  P  P22  1  0.209  0.639  0.221  1.0
  P  P23  1  0.572  0.140  0.219  1.0
[/CIF]
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