The material structure described by Li2Ni2Si2O7 crystallizes in the orthorhombic Ama2 space group. Li(1) is bonded to one O(1), one O(3), and two equivalent O(4) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent Ni(2)O5 square pyramids, corners with four equivalent Si(1)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 6-coordinate geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. In the second Ni site, Ni(2) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted NiO5 square pyramids that share corners with six equivalent Si(1)O4 tetrahedra and corners with four equivalent Li(1)O4 trigonal pyramids. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with three equivalent Ni(2)O5 square pyramids,  a cornercorner with one Si(1)O4 tetrahedra, and corners with four equivalent Li(1)O4 trigonal pyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Li(1), one Ni(1), one Ni(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ni(2) and two equivalent Si(1) atoms. In the third O site, O(3) is bonded to one Li(1), one Ni(1), one Ni(2), and one Si(1) atom to form distorted OLiSiNi2 tetrahedra that share corners with two equivalent O(3)LiSiNi2 tetrahedra and corners with five equivalent O(4)Li2SiNi tetrahedra. In the fourth O site, O(4) is bonded to two equivalent Li(1), one Ni(1), and one Si(1) atom to form distorted OLi2SiNi tetrahedra that share corners with three equivalent O(4)Li2SiNi tetrahedra and corners with five equivalent O(3)LiSiNi2 tetrahedra. is represented by the CIF card [CIF]
data_Li2Si2Ni2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.074
_cell_length_b   4.873
_cell_length_c   13.027
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   121.371
_symmetry_Int_Tables_number   1
_cell_volume   274.999
_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  0.342  0.596  0.586  1.0
  Li  Li1  1  0.342  0.596  0.914  1.0
  Li  Li2  1  0.747  0.404  0.414  1.0
  Li  Li3  1  0.747  0.404  0.086  1.0
  Si  Si4  1  0.399  0.704  0.364  1.0
  Si  Si5  1  0.399  0.704  0.136  1.0
  Si  Si6  1  0.695  0.296  0.636  1.0
  Si  Si7  1  0.695  0.296  0.864  1.0
  Ni  Ni8  1  0.036  0.000  0.000  1.0
  Ni  Ni9  1  0.036  0.000  0.500  1.0
  Ni  Ni10  1  0.022  0.010  0.250  1.0
  Ni  Ni11  1  0.012  0.990  0.750  1.0
  O  O12  1  0.143  0.813  0.135  1.0
  O  O13  1  0.143  0.813  0.365  1.0
  O  O14  1  0.363  0.515  0.250  1.0
  O  O15  1  0.731  0.980  0.870  1.0
  O  O16  1  0.731  0.980  0.630  1.0
  O  O17  1  0.363  0.448  0.051  1.0
  O  O18  1  0.363  0.448  0.449  1.0
  O  O19  1  0.331  0.187  0.865  1.0
  O  O20  1  0.331  0.187  0.635  1.0
  O  O21  1  0.848  0.485  0.750  1.0
  O  O22  1  0.751  0.020  0.370  1.0
  O  O23  1  0.751  0.020  0.130  1.0
  O  O24  1  0.915  0.552  0.949  1.0
  O  O25  1  0.915  0.552  0.551  1.0
[/CIF]
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The material structure described by Li2Ni2Si2O7 crystallizes in the orthorhombic Ama2 space group. Li(1) is bonded to one O(1), one O(3), and two equivalent O(4) atoms to form distorted LiO4 trigonal pyramids that share corners with two equivalent Ni(2)O5 square pyramids, corners with four equivalent Si(1)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 6-coordinate geometry to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms. In the second Ni site, Ni(2) is bonded to one O(2), two equivalent O(1), and two equivalent O(3) atoms to form distorted NiO5 square pyramids that share corners with six equivalent Si(1)O4 tetrahedra and corners with four equivalent Li(1)O4 trigonal pyramids. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SiO4 tetrahedra that share corners with three equivalent Ni(2)O5 square pyramids,  a cornercorner with one Si(1)O4 tetrahedra, and corners with four equivalent Li(1)O4 trigonal pyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Li(1), one Ni(1), one Ni(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ni(2) and two equivalent Si(1) atoms. In the third O site, O(3) is bonded to one Li(1), one Ni(1), one Ni(2), and one Si(1) atom to form distorted OLiSiNi2 tetrahedra that share corners with two equivalent O(3)LiSiNi2 tetrahedra and corners with five equivalent O(4)Li2SiNi tetrahedra. In the fourth O site, O(4) is bonded to two equivalent Li(1), one Ni(1), and one Si(1) atom to form distorted OLi2SiNi tetrahedra that share corners with three equivalent O(4)Li2SiNi tetrahedra and corners with five equivalent O(3)LiSiNi2 tetrahedra. is represented by the CIF card [CIF]
data_Li2Si2Ni2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.074
_cell_length_b   4.873
_cell_length_c   13.027
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   121.371
_symmetry_Int_Tables_number   1
_cell_volume   274.999
_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  0.342  0.596  0.586  1.0
  Li  Li1  1  0.342  0.596  0.914  1.0
  Li  Li2  1  0.747  0.404  0.414  1.0
  Li  Li3  1  0.747  0.404  0.086  1.0
  Si  Si4  1  0.399  0.704  0.364  1.0
  Si  Si5  1  0.399  0.704  0.136  1.0
  Si  Si6  1  0.695  0.296  0.636  1.0
  Si  Si7  1  0.695  0.296  0.864  1.0
  Ni  Ni8  1  0.036  0.000  0.000  1.0
  Ni  Ni9  1  0.036  0.000  0.500  1.0
  Ni  Ni10  1  0.022  0.010  0.250  1.0
  Ni  Ni11  1  0.012  0.990  0.750  1.0
  O  O12  1  0.143  0.813  0.135  1.0
  O  O13  1  0.143  0.813  0.365  1.0
  O  O14  1  0.363  0.515  0.250  1.0
  O  O15  1  0.731  0.980  0.870  1.0
  O  O16  1  0.731  0.980  0.630  1.0
  O  O17  1  0.363  0.448  0.051  1.0
  O  O18  1  0.363  0.448  0.449  1.0
  O  O19  1  0.331  0.187  0.865  1.0
  O  O20  1  0.331  0.187  0.635  1.0
  O  O21  1  0.848  0.485  0.750  1.0
  O  O22  1  0.751  0.020  0.370  1.0
  O  O23  1  0.751  0.020  0.130  1.0
  O  O24  1  0.915  0.552  0.949  1.0
  O  O25  1  0.915  0.552  0.551  1.0
[/CIF]
.