The structure described by Li2NiSiO4 is beta beryllia-derived structured and crystallizes in the orthorhombic Pnma space group. Li(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Ni(1)O4 tetrahedra. Ni(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form NiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Li(1)O4 tetrahedra. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form SiO4 tetrahedra that share corners with four equivalent Ni(1)O4 tetrahedra and corners with eight equivalent Li(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), one Ni(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi2SiNi tetrahedra. In the second O site, O(2) is bonded to two equivalent Li(1), one Ni(1), and one Si(1) atom to form corner-sharing OLi2SiNi tetrahedra. In the third O site, O(3) is bonded to two equivalent Li(1), one Ni(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi2SiNi trigonal pyramids. is represented by the CIF file [CIF]
data_Li2SiNiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.996
_cell_length_b   6.341
_cell_length_c   10.665
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   337.835
_cell_formula_units_Z   4
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  0.203  0.994  0.666  1.0
  Li  Li1  1  0.297  0.994  0.166  1.0
  Li  Li2  1  0.203  0.506  0.666  1.0
  Li  Li3  1  0.297  0.506  0.166  1.0
  Li  Li4  1  0.703  0.494  0.834  1.0
  Li  Li5  1  0.797  0.494  0.334  1.0
  Li  Li6  1  0.797  0.006  0.334  1.0
  Li  Li7  1  0.703  0.006  0.834  1.0
  Si  Si8  1  0.191  0.250  0.916  1.0
  Si  Si9  1  0.309  0.250  0.416  1.0
  Si  Si10  1  0.691  0.750  0.584  1.0
  Si  Si11  1  0.809  0.750  0.084  1.0
  Ni  Ni12  1  0.801  0.250  0.586  1.0
  Ni  Ni13  1  0.699  0.250  0.086  1.0
  Ni  Ni14  1  0.301  0.750  0.914  1.0
  Ni  Ni15  1  0.199  0.750  0.414  1.0
  O  O16  1  0.299  0.038  0.842  1.0
  O  O17  1  0.201  0.038  0.342  1.0
  O  O18  1  0.860  0.250  0.916  1.0
  O  O19  1  0.204  0.250  0.563  1.0
  O  O20  1  0.296  0.250  0.063  1.0
  O  O21  1  0.640  0.250  0.416  1.0
  O  O22  1  0.299  0.462  0.842  1.0
  O  O23  1  0.201  0.462  0.342  1.0
  O  O24  1  0.701  0.538  0.158  1.0
  O  O25  1  0.799  0.538  0.658  1.0
  O  O26  1  0.704  0.750  0.937  1.0
  O  O27  1  0.360  0.750  0.584  1.0
  O  O28  1  0.796  0.750  0.437  1.0
  O  O29  1  0.140  0.750  0.084  1.0
  O  O30  1  0.799  0.962  0.658  1.0
  O  O31  1  0.701  0.962  0.158  1.0
[/CIF]
.
The structure described by Li2NiSiO4 is beta beryllia-derived structured and crystallizes in the orthorhombic Pnma space group. Li(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form LiO4 tetrahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and  an edgeedge with one Ni(1)O4 tetrahedra. Ni(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form NiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Si(1)O4 tetrahedra, and edges with two equivalent Li(1)O4 tetrahedra. Si(1) is bonded to one O(2), one O(3), and two equivalent O(1) atoms to form SiO4 tetrahedra that share corners with four equivalent Ni(1)O4 tetrahedra and corners with eight equivalent Li(1)O4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Li(1), one Ni(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi2SiNi tetrahedra. In the second O site, O(2) is bonded to two equivalent Li(1), one Ni(1), and one Si(1) atom to form corner-sharing OLi2SiNi tetrahedra. In the third O site, O(3) is bonded to two equivalent Li(1), one Ni(1), and one Si(1) atom to form a mixture of distorted corner and edge-sharing OLi2SiNi trigonal pyramids. is represented by the CIF file [CIF]
data_Li2SiNiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.996
_cell_length_b   6.341
_cell_length_c   10.665
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   337.835
_cell_formula_units_Z   4
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  0.203  0.994  0.666  1.0
  Li  Li1  1  0.297  0.994  0.166  1.0
  Li  Li2  1  0.203  0.506  0.666  1.0
  Li  Li3  1  0.297  0.506  0.166  1.0
  Li  Li4  1  0.703  0.494  0.834  1.0
  Li  Li5  1  0.797  0.494  0.334  1.0
  Li  Li6  1  0.797  0.006  0.334  1.0
  Li  Li7  1  0.703  0.006  0.834  1.0
  Si  Si8  1  0.191  0.250  0.916  1.0
  Si  Si9  1  0.309  0.250  0.416  1.0
  Si  Si10  1  0.691  0.750  0.584  1.0
  Si  Si11  1  0.809  0.750  0.084  1.0
  Ni  Ni12  1  0.801  0.250  0.586  1.0
  Ni  Ni13  1  0.699  0.250  0.086  1.0
  Ni  Ni14  1  0.301  0.750  0.914  1.0
  Ni  Ni15  1  0.199  0.750  0.414  1.0
  O  O16  1  0.299  0.038  0.842  1.0
  O  O17  1  0.201  0.038  0.342  1.0
  O  O18  1  0.860  0.250  0.916  1.0
  O  O19  1  0.204  0.250  0.563  1.0
  O  O20  1  0.296  0.250  0.063  1.0
  O  O21  1  0.640  0.250  0.416  1.0
  O  O22  1  0.299  0.462  0.842  1.0
  O  O23  1  0.201  0.462  0.342  1.0
  O  O24  1  0.701  0.538  0.158  1.0
  O  O25  1  0.799  0.538  0.658  1.0
  O  O26  1  0.704  0.750  0.937  1.0
  O  O27  1  0.360  0.750  0.584  1.0
  O  O28  1  0.796  0.750  0.437  1.0
  O  O29  1  0.140  0.750  0.084  1.0
  O  O30  1  0.799  0.962  0.658  1.0
  O  O31  1  0.701  0.962  0.158  1.0
[/CIF]
.