The crystal structure described by Li6NiO4 crystallizes in the orthorhombic P2_12_12 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and edges with two equivalent Li(2)O4 tetrahedra. In the second Li site, Li(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and edges with two equivalent Li(1)O4 tetrahedra. In the third Li site, Li(3) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, edges with two equivalent Li(2)O4 tetrahedra, and edges with two equivalent Li(4)O4 tetrahedra. In the fourth Li site, Li(4) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, edges with two equivalent Li(2)O4 tetrahedra, and edges with two equivalent Li(3)O4 tetrahedra. Ni(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted NiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra, corners with four equivalent Li(3)O4 tetrahedra, corners with four equivalent Li(4)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, and edges with two equivalent Li(2)O4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(3), one Li(4), two equivalent Li(1), two equivalent Li(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OLi6Ni pentagonal bipyramids. In the second O site, O(2) is bonded to one Li(3), one Li(4), two equivalent Li(1), two equivalent Li(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OLi6Ni pentagonal bipyramids. is represented by the CIF card [CIF]
data_Li6NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.601
_cell_length_b   6.600
_cell_length_c   4.658
_cell_angle_alpha   90.001
_cell_angle_beta   89.997
_cell_angle_gamma   90.052
_symmetry_Int_Tables_number   1
_cell_volume   202.916
_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  0.036  0.536  0.750  1.0
  Li  Li1  1  0.028  0.972  0.750  1.0
  Li  Li2  1  0.250  0.250  0.697  1.0
  Li  Li3  1  0.250  0.250  0.197  1.0
  Li  Li4  1  0.472  0.528  0.750  1.0
  Li  Li5  1  0.464  0.964  0.750  1.0
  Li  Li6  1  0.528  0.028  0.250  1.0
  Li  Li7  1  0.536  0.464  0.250  1.0
  Li  Li8  1  0.750  0.750  0.303  1.0
  Li  Li9  1  0.750  0.750  0.803  1.0
  Li  Li10  1  0.964  0.036  0.250  1.0
  Li  Li11  1  0.972  0.472  0.250  1.0
  Ni  Ni12  1  0.250  0.750  0.250  1.0
  Ni  Ni13  1  0.750  0.250  0.752  1.0
  O  O14  1  0.014  0.260  0.959  1.0
  O  O15  1  0.240  0.014  0.458  1.0
  O  O16  1  0.260  0.486  0.458  1.0
  O  O17  1  0.486  0.240  0.959  1.0
  O  O18  1  0.514  0.740  0.041  1.0
  O  O19  1  0.740  0.987  0.542  1.0
  O  O20  1  0.760  0.514  0.542  1.0
  O  O21  1  0.986  0.759  0.041  1.0
[/CIF]
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The crystal structure described by Li6NiO4 crystallizes in the orthorhombic P2_12_12 space group. There are four inequivalent Li sites. In the first Li site, Li(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and edges with two equivalent Li(2)O4 tetrahedra. In the second Li site, Li(2) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted LiO4 tetrahedra that share corners with two equivalent Li(3)O4 tetrahedra, corners with two equivalent Li(4)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra,  an edgeedge with one Li(3)O4 tetrahedra,  an edgeedge with one Li(4)O4 tetrahedra,  an edgeedge with one Ni(1)O4 tetrahedra, and edges with two equivalent Li(1)O4 tetrahedra. In the third Li site, Li(3) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, edges with two equivalent Li(2)O4 tetrahedra, and edges with two equivalent Li(4)O4 tetrahedra. In the fourth Li site, Li(4) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form LiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, edges with two equivalent Li(2)O4 tetrahedra, and edges with two equivalent Li(3)O4 tetrahedra. Ni(1) is bonded to two equivalent O(1) and two equivalent O(2) atoms to form distorted NiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Li(2)O4 tetrahedra, corners with four equivalent Li(3)O4 tetrahedra, corners with four equivalent Li(4)O4 tetrahedra, edges with two equivalent Li(1)O4 tetrahedra, and edges with two equivalent Li(2)O4 tetrahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Li(3), one Li(4), two equivalent Li(1), two equivalent Li(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OLi6Ni pentagonal bipyramids. In the second O site, O(2) is bonded to one Li(3), one Li(4), two equivalent Li(1), two equivalent Li(2), and one Ni(1) atom to form a mixture of distorted edge and corner-sharing OLi6Ni pentagonal bipyramids. is represented by the CIF card [CIF]
data_Li6NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.601
_cell_length_b   6.600
_cell_length_c   4.658
_cell_angle_alpha   90.001
_cell_angle_beta   89.997
_cell_angle_gamma   90.052
_symmetry_Int_Tables_number   1
_cell_volume   202.916
_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  0.036  0.536  0.750  1.0
  Li  Li1  1  0.028  0.972  0.750  1.0
  Li  Li2  1  0.250  0.250  0.697  1.0
  Li  Li3  1  0.250  0.250  0.197  1.0
  Li  Li4  1  0.472  0.528  0.750  1.0
  Li  Li5  1  0.464  0.964  0.750  1.0
  Li  Li6  1  0.528  0.028  0.250  1.0
  Li  Li7  1  0.536  0.464  0.250  1.0
  Li  Li8  1  0.750  0.750  0.303  1.0
  Li  Li9  1  0.750  0.750  0.803  1.0
  Li  Li10  1  0.964  0.036  0.250  1.0
  Li  Li11  1  0.972  0.472  0.250  1.0
  Ni  Ni12  1  0.250  0.750  0.250  1.0
  Ni  Ni13  1  0.750  0.250  0.752  1.0
  O  O14  1  0.014  0.260  0.959  1.0
  O  O15  1  0.240  0.014  0.458  1.0
  O  O16  1  0.260  0.486  0.458  1.0
  O  O17  1  0.486  0.240  0.959  1.0
  O  O18  1  0.514  0.740  0.041  1.0
  O  O19  1  0.740  0.987  0.542  1.0
  O  O20  1  0.760  0.514  0.542  1.0
  O  O21  1  0.986  0.759  0.041  1.0
[/CIF]
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