The structure described by MgNb2(GaO4)2 crystallizes in the monoclinic C2 space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(1) atoms. Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms. Ga(1) is bonded to one O(1), one O(2), one O(4), and three equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing GaO6 octahedra. The corner-sharing octahedral tilt angles are 35°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Nb(1), and one Ga(1) atom to form OMg2NbGa tetrahedra that share corners with four equivalent O(1)Mg2NbGa tetrahedra, corners with four equivalent O(3)NbGa3 trigonal pyramids, and  an edgeedge with one O(1)Mg2NbGa tetrahedra. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Nb(1) and one Ga(1) atom. In the third O site, O(3) is bonded to one Nb(1) and three equivalent Ga(1) atoms to form distorted ONbGa3 trigonal pyramids that share corners with four equivalent O(1)Mg2NbGa tetrahedra, corners with two equivalent O(3)NbGa3 trigonal pyramids, and edges with two equivalent O(3)NbGa3 trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Nb(1) and one Ga(1) atom. is represented by the CIF card [CIF]
data_MgNb2(GaO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.694
_cell_length_b   6.884
_cell_length_c   6.812
_cell_angle_alpha   109.388
_cell_angle_beta   90.000
_cell_angle_gamma   105.563
_symmetry_Int_Tables_number   1
_cell_volume   156.668
_cell_formula_units_Z   1
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
  Mg  Mg0  1  0.500  0.000  0.500  1.0
  Nb  Nb1  1  0.107  0.219  0.215  1.0
  Nb  Nb2  1  0.889  0.781  0.785  1.0
  Ga  Ga3  1  0.188  0.379  0.805  1.0
  Ga  Ga4  1  0.809  0.621  0.195  1.0
  O  O5  1  0.900  0.803  0.485  1.0
  O  O6  1  0.097  0.197  0.515  1.0
  O  O7  1  0.942  0.889  0.116  1.0
  O  O8  1  0.053  0.111  0.884  1.0
  O  O9  1  0.263  0.530  0.147  1.0
  O  O10  1  0.733  0.470  0.853  1.0
  O  O11  1  0.332  0.668  0.736  1.0
  O  O12  1  0.664  0.332  0.264  1.0
[/CIF]
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The structure described by MgNb2(GaO4)2 crystallizes in the monoclinic C2 space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to four equivalent O(1) atoms. Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms. Ga(1) is bonded to one O(1), one O(2), one O(4), and three equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing GaO6 octahedra. The corner-sharing octahedral tilt angles are 35°. There are four inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Nb(1), and one Ga(1) atom to form OMg2NbGa tetrahedra that share corners with four equivalent O(1)Mg2NbGa tetrahedra, corners with four equivalent O(3)NbGa3 trigonal pyramids, and  an edgeedge with one O(1)Mg2NbGa tetrahedra. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Nb(1) and one Ga(1) atom. In the third O site, O(3) is bonded to one Nb(1) and three equivalent Ga(1) atoms to form distorted ONbGa3 trigonal pyramids that share corners with four equivalent O(1)Mg2NbGa tetrahedra, corners with two equivalent O(3)NbGa3 trigonal pyramids, and edges with two equivalent O(3)NbGa3 trigonal pyramids. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Nb(1) and one Ga(1) atom. is represented by the CIF card [CIF]
data_MgNb2(GaO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.694
_cell_length_b   6.884
_cell_length_c   6.812
_cell_angle_alpha   109.388
_cell_angle_beta   90.000
_cell_angle_gamma   105.563
_symmetry_Int_Tables_number   1
_cell_volume   156.668
_cell_formula_units_Z   1
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
  Mg  Mg0  1  0.500  0.000  0.500  1.0
  Nb  Nb1  1  0.107  0.219  0.215  1.0
  Nb  Nb2  1  0.889  0.781  0.785  1.0
  Ga  Ga3  1  0.188  0.379  0.805  1.0
  Ga  Ga4  1  0.809  0.621  0.195  1.0
  O  O5  1  0.900  0.803  0.485  1.0
  O  O6  1  0.097  0.197  0.515  1.0
  O  O7  1  0.942  0.889  0.116  1.0
  O  O8  1  0.053  0.111  0.884  1.0
  O  O9  1  0.263  0.530  0.147  1.0
  O  O10  1  0.733  0.470  0.853  1.0
  O  O11  1  0.332  0.668  0.736  1.0
  O  O12  1  0.664  0.332  0.264  1.0
[/CIF]
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