The structure described by Li2NiAlO4 is beta beryllia-derived structured and crystallizes in the monoclinic P2_1/c 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 LiO4 tetrahedra that share corners with four equivalent Ni(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra, corners with two equivalent Li(2)O4 trigonal pyramids, and  an edgeedge with one Li(2)O4 trigonal pyramid. 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 trigonal pyramids that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra,  an edgeedge with one Li(1)O4 tetrahedra, and  an edgeedge with one Ni(1)O4 tetrahedra. Ni(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form NiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra, corners with two equivalent Li(2)O4 trigonal pyramids, and  an edgeedge with one Li(2)O4 trigonal pyramid. Al(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AlO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, and corners with four equivalent Li(2)O4 trigonal pyramids. 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 Al(1) atom to form a mixture of corner and edge-sharing OLi2AlNi tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Ni(1), and one Al(1) atom to form a mixture of corner and edge-sharing OLi2AlNi tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Ni(1), and one Al(1) atom to form a mixture of distorted corner and edge-sharing OLi2AlNi trigonal pyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Ni(1), and one Al(1) atom to form corner-sharing OLi2AlNi tetrahedra. is represented by the CIF file [CIF]
data_Li2AlNiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.729
_cell_length_b   5.098
_cell_length_c   8.146
_cell_angle_alpha   51.449
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   348.477
_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  0.834  0.300  0.011  1.0
  Li  Li1  1  0.080  0.055  0.242  1.0
  Li  Li2  1  0.580  0.945  0.258  1.0
  Li  Li3  1  0.334  0.700  0.489  1.0
  Li  Li4  1  0.666  0.300  0.511  1.0
  Li  Li5  1  0.420  0.055  0.742  1.0
  Li  Li6  1  0.920  0.945  0.758  1.0
  Li  Li7  1  0.166  0.700  0.989  1.0
  Al  Al8  1  0.412  0.444  0.240  1.0
  Al  Al9  1  0.912  0.556  0.260  1.0
  Al  Al10  1  0.088  0.444  0.740  1.0
  Al  Al11  1  0.588  0.556  0.760  1.0
  Ni  Ni12  1  0.667  0.810  0.008  1.0
  Ni  Ni13  1  0.167  0.190  0.492  1.0
  Ni  Ni14  1  0.833  0.810  0.508  1.0
  Ni  Ni15  1  0.333  0.190  0.992  1.0
  O  O16  1  0.336  0.799  0.017  1.0
  O  O17  1  0.832  0.679  0.030  1.0
  O  O18  1  0.070  0.462  0.250  1.0
  O  O19  1  0.408  0.106  0.228  1.0
  O  O20  1  0.908  0.894  0.272  1.0
  O  O21  1  0.570  0.538  0.250  1.0
  O  O22  1  0.332  0.321  0.470  1.0
  O  O23  1  0.836  0.201  0.483  1.0
  O  O24  1  0.164  0.799  0.517  1.0
  O  O25  1  0.668  0.679  0.530  1.0
  O  O26  1  0.430  0.462  0.750  1.0
  O  O27  1  0.092  0.106  0.728  1.0
  O  O28  1  0.592  0.894  0.772  1.0
  O  O29  1  0.930  0.538  0.750  1.0
  O  O30  1  0.168  0.321  0.970  1.0
  O  O31  1  0.664  0.201  0.983  1.0
[/CIF]
.
The structure described by Li2NiAlO4 is beta beryllia-derived structured and crystallizes in the monoclinic P2_1/c 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 LiO4 tetrahedra that share corners with four equivalent Ni(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra, corners with two equivalent Li(2)O4 trigonal pyramids, and  an edgeedge with one Li(2)O4 trigonal pyramid. 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 trigonal pyramids that share corners with two equivalent Li(1)O4 tetrahedra, corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra,  an edgeedge with one Li(1)O4 tetrahedra, and  an edgeedge with one Ni(1)O4 tetrahedra. Ni(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form NiO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Al(1)O4 tetrahedra, corners with two equivalent Li(2)O4 trigonal pyramids, and  an edgeedge with one Li(2)O4 trigonal pyramid. Al(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form AlO4 tetrahedra that share corners with four equivalent Li(1)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, and corners with four equivalent Li(2)O4 trigonal pyramids. 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 Al(1) atom to form a mixture of corner and edge-sharing OLi2AlNi tetrahedra. In the second O site, O(2) is bonded to one Li(1), one Li(2), one Ni(1), and one Al(1) atom to form a mixture of corner and edge-sharing OLi2AlNi tetrahedra. In the third O site, O(3) is bonded to one Li(1), one Li(2), one Ni(1), and one Al(1) atom to form a mixture of distorted corner and edge-sharing OLi2AlNi trigonal pyramids. In the fourth O site, O(4) is bonded to one Li(1), one Li(2), one Ni(1), and one Al(1) atom to form corner-sharing OLi2AlNi tetrahedra. is represented by the CIF file [CIF]
data_Li2AlNiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.729
_cell_length_b   5.098
_cell_length_c   8.146
_cell_angle_alpha   51.449
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   348.477
_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  0.834  0.300  0.011  1.0
  Li  Li1  1  0.080  0.055  0.242  1.0
  Li  Li2  1  0.580  0.945  0.258  1.0
  Li  Li3  1  0.334  0.700  0.489  1.0
  Li  Li4  1  0.666  0.300  0.511  1.0
  Li  Li5  1  0.420  0.055  0.742  1.0
  Li  Li6  1  0.920  0.945  0.758  1.0
  Li  Li7  1  0.166  0.700  0.989  1.0
  Al  Al8  1  0.412  0.444  0.240  1.0
  Al  Al9  1  0.912  0.556  0.260  1.0
  Al  Al10  1  0.088  0.444  0.740  1.0
  Al  Al11  1  0.588  0.556  0.760  1.0
  Ni  Ni12  1  0.667  0.810  0.008  1.0
  Ni  Ni13  1  0.167  0.190  0.492  1.0
  Ni  Ni14  1  0.833  0.810  0.508  1.0
  Ni  Ni15  1  0.333  0.190  0.992  1.0
  O  O16  1  0.336  0.799  0.017  1.0
  O  O17  1  0.832  0.679  0.030  1.0
  O  O18  1  0.070  0.462  0.250  1.0
  O  O19  1  0.408  0.106  0.228  1.0
  O  O20  1  0.908  0.894  0.272  1.0
  O  O21  1  0.570  0.538  0.250  1.0
  O  O22  1  0.332  0.321  0.470  1.0
  O  O23  1  0.836  0.201  0.483  1.0
  O  O24  1  0.164  0.799  0.517  1.0
  O  O25  1  0.668  0.679  0.530  1.0
  O  O26  1  0.430  0.462  0.750  1.0
  O  O27  1  0.092  0.106  0.728  1.0
  O  O28  1  0.592  0.894  0.772  1.0
  O  O29  1  0.930  0.538  0.750  1.0
  O  O30  1  0.168  0.321  0.970  1.0
  O  O31  1  0.664  0.201  0.983  1.0
[/CIF]
.