The material described by LiNiP2O7 crystallizes in the monoclinic P2_1 space group. Li(1) is bonded in a see-saw-like geometry to one O(2), one O(3), one O(4), and one O(5) atom. Ni(1) is bonded to one O(2), one O(3), one O(4), one O(5), 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(2), one O(3), and one O(5) 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 46-49°. In the second P site, P(2) is bonded to one O(1), one O(4), one O(6), 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(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-52°. 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 3-coordinate geometry to one Li(1), one Ni(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Li(1), one Ni(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped 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 bent 120 degrees geometry to one Ni(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiNiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.338
_cell_length_b   4.904
_cell_length_c   7.162
_cell_angle_alpha   70.015
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   275.222
_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  0.854  0.823  0.658  1.0
  Li  Li1  1  0.354  0.177  0.342  1.0
  Ni  Ni2  1  0.002  0.221  0.279  1.0
  Ni  Ni3  1  0.502  0.779  0.721  1.0
  P  P4  1  0.679  0.400  0.474  1.0
  P  P5  1  0.281  0.209  0.921  1.0
  P  P6  1  0.781  0.791  0.079  1.0
  P  P7  1  0.179  0.600  0.526  1.0
  O  O8  1  0.154  0.393  0.758  1.0
  O  O9  1  0.180  0.405  0.400  1.0
  O  O10  1  0.036  0.807  0.488  1.0
  O  O11  1  0.198  0.141  0.121  1.0
  O  O12  1  0.536  0.193  0.512  1.0
  O  O13  1  0.339  0.757  0.514  1.0
  O  O14  1  0.698  0.859  0.879  1.0
  O  O15  1  0.934  0.610  0.078  1.0
  O  O16  1  0.837  0.054  0.128  1.0
  O  O17  1  0.839  0.243  0.486  1.0
  O  O18  1  0.337  0.946  0.872  1.0
  O  O19  1  0.680  0.595  0.600  1.0
  O  O20  1  0.654  0.607  0.242  1.0
  O  O21  1  0.434  0.390  0.922  1.0
[/CIF]
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The material described by LiNiP2O7 crystallizes in the monoclinic P2_1 space group. Li(1) is bonded in a see-saw-like geometry to one O(2), one O(3), one O(4), and one O(5) atom. Ni(1) is bonded to one O(2), one O(3), one O(4), one O(5), 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(2), one O(3), and one O(5) 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 46-49°. In the second P site, P(2) is bonded to one O(1), one O(4), one O(6), 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(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 33-52°. 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 3-coordinate geometry to one Li(1), one Ni(1), and one P(1) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Li(1), one Ni(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a distorted T-shaped 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 bent 120 degrees geometry to one Ni(1) and one P(2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Ni(1) and one P(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_LiNiP2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.338
_cell_length_b   4.904
_cell_length_c   7.162
_cell_angle_alpha   70.015
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   275.222
_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  0.854  0.823  0.658  1.0
  Li  Li1  1  0.354  0.177  0.342  1.0
  Ni  Ni2  1  0.002  0.221  0.279  1.0
  Ni  Ni3  1  0.502  0.779  0.721  1.0
  P  P4  1  0.679  0.400  0.474  1.0
  P  P5  1  0.281  0.209  0.921  1.0
  P  P6  1  0.781  0.791  0.079  1.0
  P  P7  1  0.179  0.600  0.526  1.0
  O  O8  1  0.154  0.393  0.758  1.0
  O  O9  1  0.180  0.405  0.400  1.0
  O  O10  1  0.036  0.807  0.488  1.0
  O  O11  1  0.198  0.141  0.121  1.0
  O  O12  1  0.536  0.193  0.512  1.0
  O  O13  1  0.339  0.757  0.514  1.0
  O  O14  1  0.698  0.859  0.879  1.0
  O  O15  1  0.934  0.610  0.078  1.0
  O  O16  1  0.837  0.054  0.128  1.0
  O  O17  1  0.839  0.243  0.486  1.0
  O  O18  1  0.337  0.946  0.872  1.0
  O  O19  1  0.680  0.595  0.600  1.0
  O  O20  1  0.654  0.607  0.242  1.0
  O  O21  1  0.434  0.390  0.922  1.0
[/CIF]
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