The crystal structure described by Li2NiSi2O6 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(4), one O(5), and two equivalent O(7) atoms. In the second Li site, Li(2) is bonded in a 5-coordinate geometry to one O(1), one O(4), one O(5), and two equivalent O(6) atoms. Ni(1) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form NiO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Ni(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Ni(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Li(1), one Li(2), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a linear geometry to two equivalent Si(2) atoms. 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 trigonal pyramids. In the fifth O site, O(5) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(2) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi trigonal pyramids. In the sixth O site, O(6) is bonded to two equivalent Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi trigonal pyramids. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Li(1), one Ni(1), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Si2NiO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.563
_cell_length_b   5.570
_cell_length_c   9.432
_cell_angle_alpha   90.995
_cell_angle_beta   91.017
_cell_angle_gamma   117.163
_symmetry_Int_Tables_number   1
_cell_volume   259.879
_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  0.740  0.397  0.881  1.0
  Li  Li1  1  0.396  0.741  0.381  1.0
  Li  Li2  1  0.603  0.259  0.619  1.0
  Li  Li3  1  0.260  0.602  0.119  1.0
  Ni  Ni4  1  0.258  0.743  0.750  1.0
  Ni  Ni5  1  0.742  0.257  0.249  1.0
  O  O6  1  0.885  0.115  0.750  1.0
  O  O7  1  0.115  0.885  0.250  1.0
  O  O8  1  0.000  0.001  0.500  1.0
  O  O9  1  1.000  1.000  0.000  1.0
  O  O10  1  0.866  0.626  0.700  1.0
  O  O11  1  0.626  0.866  0.200  1.0
  O  O12  1  0.374  0.134  0.800  1.0
  O  O13  1  0.134  0.374  0.300  1.0
  O  O14  1  0.490  0.770  0.587  1.0
  O  O15  1  0.768  0.491  0.086  1.0
  O  O16  1  0.232  0.509  0.913  1.0
  O  O17  1  0.510  0.231  0.413  1.0
  Si  Si18  1  0.804  0.860  0.632  1.0
  Si  Si19  1  0.860  0.804  0.132  1.0
  Si  Si20  1  0.140  0.196  0.868  1.0
  Si  Si21  1  0.196  0.140  0.368  1.0
[/CIF]
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The crystal structure described by Li2NiSi2O6 crystallizes in the triclinic P-1 space group. There are two inequivalent Li sites. In the first Li site, Li(1) is bonded in a 5-coordinate geometry to one O(1), one O(4), one O(5), and two equivalent O(7) atoms. In the second Li site, Li(2) is bonded in a 5-coordinate geometry to one O(1), one O(4), one O(5), and two equivalent O(6) atoms. Ni(1) is bonded to one O(4), one O(5), one O(6), and one O(7) atom to form NiO4 tetrahedra that share corners with two equivalent Si(1)O4 tetrahedra and corners with two equivalent Si(2)O4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Ni(1)O4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(5), and one O(7) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, and corners with two equivalent Ni(1)O4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Li(1), one Li(2), one Si(1), and one Si(2) atom. In the second O site, O(2) is bonded in a linear geometry to two equivalent Si(1) atoms. In the third O site, O(3) is bonded in a linear geometry to two equivalent Si(2) atoms. 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 trigonal pyramids. In the fifth O site, O(5) is bonded to one Li(1), one Li(2), one Ni(1), and one Si(2) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi trigonal pyramids. In the sixth O site, O(6) is bonded to two equivalent Li(2), one Ni(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing OLi2SiNi trigonal pyramids. In the seventh O site, O(7) is bonded in a 4-coordinate geometry to two equivalent Li(1), one Ni(1), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Li2Si2NiO6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.563
_cell_length_b   5.570
_cell_length_c   9.432
_cell_angle_alpha   90.995
_cell_angle_beta   91.017
_cell_angle_gamma   117.163
_symmetry_Int_Tables_number   1
_cell_volume   259.879
_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  0.740  0.397  0.881  1.0
  Li  Li1  1  0.396  0.741  0.381  1.0
  Li  Li2  1  0.603  0.259  0.619  1.0
  Li  Li3  1  0.260  0.602  0.119  1.0
  Ni  Ni4  1  0.258  0.743  0.750  1.0
  Ni  Ni5  1  0.742  0.257  0.249  1.0
  O  O6  1  0.885  0.115  0.750  1.0
  O  O7  1  0.115  0.885  0.250  1.0
  O  O8  1  0.000  0.001  0.500  1.0
  O  O9  1  1.000  1.000  0.000  1.0
  O  O10  1  0.866  0.626  0.700  1.0
  O  O11  1  0.626  0.866  0.200  1.0
  O  O12  1  0.374  0.134  0.800  1.0
  O  O13  1  0.134  0.374  0.300  1.0
  O  O14  1  0.490  0.770  0.587  1.0
  O  O15  1  0.768  0.491  0.086  1.0
  O  O16  1  0.232  0.509  0.913  1.0
  O  O17  1  0.510  0.231  0.413  1.0
  Si  Si18  1  0.804  0.860  0.632  1.0
  Si  Si19  1  0.860  0.804  0.132  1.0
  Si  Si20  1  0.140  0.196  0.868  1.0
  Si  Si21  1  0.196  0.140  0.368  1.0
[/CIF]
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