The material described by Li2NiSiO4 crystallizes in the trigonal P3_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with four equivalent Li(2)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form LiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. Ni(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. 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 four equivalent Li(1)O4 tetrahedra and corners with four equivalent Li(2)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi tetrahedra. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi tetrahedra. is represented by the CIF card [CIF]
data_Li2SiNiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.018
_cell_length_b   5.018
_cell_length_c   11.487
_cell_angle_alpha   90.021
_cell_angle_beta   90.037
_cell_angle_gamma   60.007
_symmetry_Int_Tables_number   1
_cell_volume   250.496
_cell_formula_units_Z   3
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  0.567  0.120  0.585  1.0
  Li  Li1  1  0.314  0.566  0.919  1.0
  Li  Li2  1  0.120  0.313  0.252  1.0
  Li  Li3  1  0.659  0.877  0.081  1.0
  Li  Li4  1  0.877  0.465  0.748  1.0
  Li  Li5  1  0.464  0.659  0.414  1.0
  Ni  Ni6  1  0.447  0.522  0.160  1.0
  Ni  Ni7  1  0.031  0.447  0.493  1.0
  Ni  Ni8  1  0.521  0.032  0.826  1.0
  O  O9  1  0.692  0.149  0.963  1.0
  O  O10  1  0.159  0.691  0.296  1.0
  O  O11  1  0.150  0.159  0.630  1.0
  O  O12  1  0.321  0.574  0.559  1.0
  O  O13  1  0.573  0.105  0.226  1.0
  O  O14  1  0.105  0.322  0.893  1.0
  O  O15  1  0.851  0.872  0.707  1.0
  O  O16  1  0.872  0.277  0.374  1.0
  O  O17  1  0.277  0.851  0.041  1.0
  O  O18  1  0.875  0.433  0.111  1.0
  O  O19  1  0.692  0.875  0.445  1.0
  O  O20  1  0.433  0.692  0.778  1.0
  Si  Si21  1  0.188  0.822  0.668  1.0
  Si  Si22  1  0.822  0.990  0.334  1.0
  Si  Si23  1  0.990  0.188  0.001  1.0
[/CIF]
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The material described by Li2NiSiO4 crystallizes in the trigonal P3_1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form distorted LiO4 tetrahedra that share corners with four equivalent Li(2)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. In the second Li site, Li(2) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form LiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra and corners with four equivalent Si(1)O4 tetrahedra. Ni(1) is bonded in a distorted rectangular see-saw-like geometry to one O(1), one O(2), one O(3), and one O(4) atom. 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 four equivalent Li(1)O4 tetrahedra and corners with four equivalent Li(2)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi tetrahedra. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi tetrahedra. is represented by the CIF card [CIF]
data_Li2SiNiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.018
_cell_length_b   5.018
_cell_length_c   11.487
_cell_angle_alpha   90.021
_cell_angle_beta   90.037
_cell_angle_gamma   60.007
_symmetry_Int_Tables_number   1
_cell_volume   250.496
_cell_formula_units_Z   3
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  0.567  0.120  0.585  1.0
  Li  Li1  1  0.314  0.566  0.919  1.0
  Li  Li2  1  0.120  0.313  0.252  1.0
  Li  Li3  1  0.659  0.877  0.081  1.0
  Li  Li4  1  0.877  0.465  0.748  1.0
  Li  Li5  1  0.464  0.659  0.414  1.0
  Ni  Ni6  1  0.447  0.522  0.160  1.0
  Ni  Ni7  1  0.031  0.447  0.493  1.0
  Ni  Ni8  1  0.521  0.032  0.826  1.0
  O  O9  1  0.692  0.149  0.963  1.0
  O  O10  1  0.159  0.691  0.296  1.0
  O  O11  1  0.150  0.159  0.630  1.0
  O  O12  1  0.321  0.574  0.559  1.0
  O  O13  1  0.573  0.105  0.226  1.0
  O  O14  1  0.105  0.322  0.893  1.0
  O  O15  1  0.851  0.872  0.707  1.0
  O  O16  1  0.872  0.277  0.374  1.0
  O  O17  1  0.277  0.851  0.041  1.0
  O  O18  1  0.875  0.433  0.111  1.0
  O  O19  1  0.692  0.875  0.445  1.0
  O  O20  1  0.433  0.692  0.778  1.0
  Si  Si21  1  0.188  0.822  0.668  1.0
  Si  Si22  1  0.822  0.990  0.334  1.0
  Si  Si23  1  0.990  0.188  0.001  1.0
[/CIF]
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