The material described by Mg2Nb2SbO8 crystallizes in the monoclinic C2 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 6-coordinate geometry to one O(5), one O(6), two equivalent O(7), and two equivalent O(8) atoms. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to one O(7), one O(8), two equivalent O(5), and two equivalent O(6) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-64°. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O6 octahedra, and edges with two equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-64°. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted SbO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, and edges with two equivalent Sb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-64°. In the second Sb site, Sb(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted SbO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, and edges with two equivalent Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-63°. There are eight inequivalent O sites. In the first O site, O(7) is bonded to one Mg(2), two equivalent Mg(1), and one Nb(1) atom to form a mixture of corner and edge-sharing OMg3Nb trigonal pyramids. In the second O site, O(8) is bonded in a 5-coordinate geometry to one Mg(2), two equivalent Mg(1), one Nb(1), and one Nb(2) atom. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Sb(2) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Sb(1) atom. In the fifth O site, O(3) is bonded in a distorted trigonal planar geometry to one Nb(1), one Sb(1), and one Sb(2) atom. In the sixth O site, O(4) is bonded in a distorted trigonal planar geometry to one Nb(2), one Sb(1), and one Sb(2) atom. In the seventh O site, O(5) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mg(2), one Nb(1), and one Nb(2) atom. In the eighth O site, O(6) is bonded to one Mg(1), two equivalent Mg(2), and one Nb(2) atom to form a mixture of corner and edge-sharing OMg3Nb trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Nb2SbO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.654
_cell_length_b   10.654
_cell_length_c   5.373
_cell_angle_alpha   85.948
_cell_angle_beta   85.948
_cell_angle_gamma   32.627
_symmetry_Int_Tables_number   1
_cell_volume   327.931
_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
  Mg  Mg0  1  0.420  0.122  0.989  1.0
  Mg  Mg1  1  0.878  0.580  0.011  1.0
  Mg  Mg2  1  0.576  0.879  0.510  1.0
  Mg  Mg3  1  0.121  0.424  0.490  1.0
  Nb  Nb4  1  0.288  0.959  0.018  1.0
  Nb  Nb5  1  0.041  0.712  0.982  1.0
  Nb  Nb6  1  0.711  0.039  0.482  1.0
  Nb  Nb7  1  0.961  0.289  0.518  1.0
  Sb  Sb8  1  0.676  0.324  0.000  1.0
  Sb  Sb9  1  0.332  0.668  0.500  1.0
  O  O10  1  0.165  0.991  0.722  1.0
  O  O11  1  0.009  0.835  0.278  1.0
  O  O12  1  0.834  0.009  0.778  1.0
  O  O13  1  0.991  0.166  0.222  1.0
  O  O14  1  0.456  0.659  0.139  1.0
  O  O15  1  0.341  0.544  0.861  1.0
  O  O16  1  0.542  0.341  0.360  1.0
  O  O17  1  0.659  0.458  0.640  1.0
  O  O18  1  0.290  0.081  0.311  1.0
  O  O19  1  0.919  0.710  0.689  1.0
  O  O20  1  0.835  0.557  0.382  1.0
  O  O21  1  0.443  0.165  0.618  1.0
  O  O22  1  0.162  0.443  0.120  1.0
  O  O23  1  0.557  0.838  0.880  1.0
  O  O24  1  0.082  0.292  0.810  1.0
  O  O25  1  0.708  0.918  0.190  1.0
[/CIF]
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The material described by Mg2Nb2SbO8 crystallizes in the monoclinic C2 space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 6-coordinate geometry to one O(5), one O(6), two equivalent O(7), and two equivalent O(8) atoms. In the second Mg site, Mg(2) is bonded in a 6-coordinate geometry to one O(7), one O(8), two equivalent O(5), and two equivalent O(6) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O6 octahedra, and edges with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-64°. In the second Nb site, Nb(2) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O6 octahedra, and edges with two equivalent Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-64°. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form distorted SbO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, and edges with two equivalent Sb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-64°. In the second Sb site, Sb(2) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted SbO6 octahedra that share corners with four equivalent Nb(1)O6 octahedra, corners with four equivalent Nb(2)O6 octahedra, and edges with two equivalent Sb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 39-63°. There are eight inequivalent O sites. In the first O site, O(7) is bonded to one Mg(2), two equivalent Mg(1), and one Nb(1) atom to form a mixture of corner and edge-sharing OMg3Nb trigonal pyramids. In the second O site, O(8) is bonded in a 5-coordinate geometry to one Mg(2), two equivalent Mg(1), one Nb(1), and one Nb(2) atom. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Sb(2) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Sb(1) atom. In the fifth O site, O(3) is bonded in a distorted trigonal planar geometry to one Nb(1), one Sb(1), and one Sb(2) atom. In the sixth O site, O(4) is bonded in a distorted trigonal planar geometry to one Nb(2), one Sb(1), and one Sb(2) atom. In the seventh O site, O(5) is bonded in a 5-coordinate geometry to one Mg(1), two equivalent Mg(2), one Nb(1), and one Nb(2) atom. In the eighth O site, O(6) is bonded to one Mg(1), two equivalent Mg(2), and one Nb(2) atom to form a mixture of corner and edge-sharing OMg3Nb trigonal pyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_Mg2Nb2SbO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.654
_cell_length_b   10.654
_cell_length_c   5.373
_cell_angle_alpha   85.948
_cell_angle_beta   85.948
_cell_angle_gamma   32.627
_symmetry_Int_Tables_number   1
_cell_volume   327.931
_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
  Mg  Mg0  1  0.420  0.122  0.989  1.0
  Mg  Mg1  1  0.878  0.580  0.011  1.0
  Mg  Mg2  1  0.576  0.879  0.510  1.0
  Mg  Mg3  1  0.121  0.424  0.490  1.0
  Nb  Nb4  1  0.288  0.959  0.018  1.0
  Nb  Nb5  1  0.041  0.712  0.982  1.0
  Nb  Nb6  1  0.711  0.039  0.482  1.0
  Nb  Nb7  1  0.961  0.289  0.518  1.0
  Sb  Sb8  1  0.676  0.324  0.000  1.0
  Sb  Sb9  1  0.332  0.668  0.500  1.0
  O  O10  1  0.165  0.991  0.722  1.0
  O  O11  1  0.009  0.835  0.278  1.0
  O  O12  1  0.834  0.009  0.778  1.0
  O  O13  1  0.991  0.166  0.222  1.0
  O  O14  1  0.456  0.659  0.139  1.0
  O  O15  1  0.341  0.544  0.861  1.0
  O  O16  1  0.542  0.341  0.360  1.0
  O  O17  1  0.659  0.458  0.640  1.0
  O  O18  1  0.290  0.081  0.311  1.0
  O  O19  1  0.919  0.710  0.689  1.0
  O  O20  1  0.835  0.557  0.382  1.0
  O  O21  1  0.443  0.165  0.618  1.0
  O  O22  1  0.162  0.443  0.120  1.0
  O  O23  1  0.557  0.838  0.880  1.0
  O  O24  1  0.082  0.292  0.810  1.0
  O  O25  1  0.708  0.918  0.190  1.0
[/CIF]
.