The material described by NiGa2O4 is Spinel structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(5), and two equivalent O(4) atoms to form NiO4 tetrahedra that share  a cornercorner with one Ga(1)O6 octahedra, corners with two equivalent Ga(2)O6 octahedra, corners with two equivalent Ga(4)O6 octahedra, corners with three equivalent Ga(5)O6 octahedra, and corners with four equivalent Ga(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-62°. In the second Ni site, Ni(2) is bonded to one O(2), one O(6), and two equivalent O(3) atoms to form NiO4 tetrahedra that share  a cornercorner with one Ga(2)O6 octahedra, corners with two equivalent Ga(1)O6 octahedra, corners with two equivalent Ga(3)O6 octahedra, corners with three equivalent Ga(5)O6 octahedra, and corners with four equivalent Ga(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-61°. There are five inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form GaO6 octahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Ni(2)O4 tetrahedra, edges with two equivalent Ga(5)O6 octahedra, and edges with four equivalent Ga(4)O6 octahedra. In the second Ga site, Ga(2) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form GaO6 octahedra that share corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, edges with two equivalent Ga(5)O6 octahedra, and edges with four equivalent Ga(3)O6 octahedra. In the third Ga site, Ga(3) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms to form GaO6 octahedra that share corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, edges with two equivalent Ga(2)O6 octahedra, edges with two equivalent Ga(3)O6 octahedra, and edges with two equivalent Ga(5)O6 octahedra. In the fourth Ga site, Ga(4) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form GaO6 octahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Ni(2)O4 tetrahedra, edges with two equivalent Ga(1)O6 octahedra, edges with two equivalent Ga(4)O6 octahedra, and edges with two equivalent Ga(5)O6 octahedra. In the fifth Ga site, Ga(5) is bonded to one O(5), one O(6), two equivalent O(3), and two equivalent O(4) atoms to form GaO6 octahedra that share corners with three equivalent Ni(1)O4 tetrahedra, corners with three equivalent Ni(2)O4 tetrahedra,  an edgeedge with one Ga(1)O6 octahedra,  an edgeedge with one Ga(2)O6 octahedra, edges with two equivalent Ga(3)O6 octahedra, and edges with two equivalent Ga(4)O6 octahedra. There are six inequivalent O sites. In the first O site, O(5) is bonded to one Ni(1), one Ga(5), and two equivalent Ga(3) atoms to form distorted corner-sharing OGa3Ni trigonal pyramids. In the second O site, O(6) is bonded in a rectangular see-saw-like geometry to one Ni(2), one Ga(5), and two equivalent Ga(4) atoms. In the third O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ni(1), one Ga(1), and two equivalent Ga(4) atoms. In the fourth O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ni(2), one Ga(2), and two equivalent Ga(3) atoms. In the fifth O site, O(3) is bonded in a rectangular see-saw-like geometry to one Ni(2), one Ga(1), one Ga(4), and one Ga(5) atom. In the sixth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Ni(1), one Ga(2), one Ga(3), and one Ga(5) atom. is represented by the CIF card [CIF]
data_Ga2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.891
_cell_length_b   5.904
_cell_length_c   5.982
_cell_angle_alpha   60.915
_cell_angle_beta   60.514
_cell_angle_gamma   90.002
_symmetry_Int_Tables_number   1
_cell_volume   150.236
_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
  Ga  Ga0  1  0.375  0.625  0.250  1.0
  Ga  Ga1  1  0.375  0.625  0.750  1.0
  Ga  Ga2  1  0.875  0.625  0.750  1.0
  Ga  Ga3  1  0.375  0.125  0.250  1.0
  Ni  Ni4  1  1.000  0.003  0.000  1.0
  Ni  Ni5  1  0.750  0.247  0.500  1.0
  O  O6  1  0.607  0.839  0.785  1.0
  O  O7  1  0.625  0.392  0.217  1.0
  O  O8  1  0.125  0.858  0.283  1.0
  O  O9  1  0.159  0.392  0.217  1.0
  O  O10  1  0.143  0.411  0.715  1.0
  O  O11  1  0.609  0.376  0.782  1.0
  O  O12  1  0.141  0.874  0.719  1.0
  O  O13  1  0.591  0.858  0.283  1.0
[/CIF]
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The material described by NiGa2O4 is Spinel structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(1), one O(5), and two equivalent O(4) atoms to form NiO4 tetrahedra that share  a cornercorner with one Ga(1)O6 octahedra, corners with two equivalent Ga(2)O6 octahedra, corners with two equivalent Ga(4)O6 octahedra, corners with three equivalent Ga(5)O6 octahedra, and corners with four equivalent Ga(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-62°. In the second Ni site, Ni(2) is bonded to one O(2), one O(6), and two equivalent O(3) atoms to form NiO4 tetrahedra that share  a cornercorner with one Ga(2)O6 octahedra, corners with two equivalent Ga(1)O6 octahedra, corners with two equivalent Ga(3)O6 octahedra, corners with three equivalent Ga(5)O6 octahedra, and corners with four equivalent Ga(4)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-61°. There are five inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form GaO6 octahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Ni(2)O4 tetrahedra, edges with two equivalent Ga(5)O6 octahedra, and edges with four equivalent Ga(4)O6 octahedra. In the second Ga site, Ga(2) is bonded to two equivalent O(2) and four equivalent O(4) atoms to form GaO6 octahedra that share corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, edges with two equivalent Ga(5)O6 octahedra, and edges with four equivalent Ga(3)O6 octahedra. In the third Ga site, Ga(3) is bonded to two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms to form GaO6 octahedra that share corners with two equivalent Ni(2)O4 tetrahedra, corners with four equivalent Ni(1)O4 tetrahedra, edges with two equivalent Ga(2)O6 octahedra, edges with two equivalent Ga(3)O6 octahedra, and edges with two equivalent Ga(5)O6 octahedra. In the fourth Ga site, Ga(4) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(6) atoms to form GaO6 octahedra that share corners with two equivalent Ni(1)O4 tetrahedra, corners with four equivalent Ni(2)O4 tetrahedra, edges with two equivalent Ga(1)O6 octahedra, edges with two equivalent Ga(4)O6 octahedra, and edges with two equivalent Ga(5)O6 octahedra. In the fifth Ga site, Ga(5) is bonded to one O(5), one O(6), two equivalent O(3), and two equivalent O(4) atoms to form GaO6 octahedra that share corners with three equivalent Ni(1)O4 tetrahedra, corners with three equivalent Ni(2)O4 tetrahedra,  an edgeedge with one Ga(1)O6 octahedra,  an edgeedge with one Ga(2)O6 octahedra, edges with two equivalent Ga(3)O6 octahedra, and edges with two equivalent Ga(4)O6 octahedra. There are six inequivalent O sites. In the first O site, O(5) is bonded to one Ni(1), one Ga(5), and two equivalent Ga(3) atoms to form distorted corner-sharing OGa3Ni trigonal pyramids. In the second O site, O(6) is bonded in a rectangular see-saw-like geometry to one Ni(2), one Ga(5), and two equivalent Ga(4) atoms. In the third O site, O(1) is bonded in a rectangular see-saw-like geometry to one Ni(1), one Ga(1), and two equivalent Ga(4) atoms. In the fourth O site, O(2) is bonded in a rectangular see-saw-like geometry to one Ni(2), one Ga(2), and two equivalent Ga(3) atoms. In the fifth O site, O(3) is bonded in a rectangular see-saw-like geometry to one Ni(2), one Ga(1), one Ga(4), and one Ga(5) atom. In the sixth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Ni(1), one Ga(2), one Ga(3), and one Ga(5) atom. is represented by the CIF card [CIF]
data_Ga2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.891
_cell_length_b   5.904
_cell_length_c   5.982
_cell_angle_alpha   60.915
_cell_angle_beta   60.514
_cell_angle_gamma   90.002
_symmetry_Int_Tables_number   1
_cell_volume   150.236
_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
  Ga  Ga0  1  0.375  0.625  0.250  1.0
  Ga  Ga1  1  0.375  0.625  0.750  1.0
  Ga  Ga2  1  0.875  0.625  0.750  1.0
  Ga  Ga3  1  0.375  0.125  0.250  1.0
  Ni  Ni4  1  1.000  0.003  0.000  1.0
  Ni  Ni5  1  0.750  0.247  0.500  1.0
  O  O6  1  0.607  0.839  0.785  1.0
  O  O7  1  0.625  0.392  0.217  1.0
  O  O8  1  0.125  0.858  0.283  1.0
  O  O9  1  0.159  0.392  0.217  1.0
  O  O10  1  0.143  0.411  0.715  1.0
  O  O11  1  0.609  0.376  0.782  1.0
  O  O12  1  0.141  0.874  0.719  1.0
  O  O13  1  0.591  0.858  0.283  1.0
[/CIF]
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