The crystal structure described by MgNb4(SnO6)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 3-coordinate geometry to one Sn(2), one O(12), one O(6), and one O(8) atom. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(10), one O(11), one O(2), one O(3), and one O(5) atom to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 29-53°. In the second Nb site, Nb(2) is bonded to one O(1), one O(12), one O(2), one O(4), one O(6), and one O(9) atom to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 32-53°. In the third Nb site, Nb(3) is bonded to one O(1), one O(12), one O(3), one O(4), one O(6), and one O(8) atom to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 32-60°. In the fourth Nb site, Nb(4) is bonded to one O(11), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 29-60°. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a rectangular see-saw-like geometry to one O(10), one O(7), one O(8), and one O(9) atom. In the second Sn site, Sn(2) is bonded in a 5-coordinate geometry to one Mg(1), one O(10), one O(11), one O(7), and one O(8) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Nb(1), one Nb(2), and one Nb(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Nb(4) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(3), and one Nb(4) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Nb(2), one Nb(3), and one Nb(4) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Nb(2), and one Nb(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Nb(4), one Sn(1), and one Sn(2) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Nb(3), one Sn(1), and one Sn(2) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Nb(2) and one Sn(1) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Nb(1), one Sn(1), and one Sn(2) atom. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(4), and one Sn(2) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Mg(1), one Nb(2), and one Nb(3) atom. is represented by the CIF card [CIF]
data_MgNb4(SnO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.146
_cell_length_b   5.722
_cell_length_c   9.495
_cell_angle_alpha   89.486
_cell_angle_beta   110.233
_cell_angle_gamma   90.397
_symmetry_Int_Tables_number   1
_cell_volume   262.345
_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  0.480  0.802  0.870  1.0
  Nb  Nb1  1  0.405  0.164  0.373  1.0
  Nb  Nb2  1  0.128  0.344  0.672  1.0
  Nb  Nb3  1  0.606  0.855  0.610  1.0
  Nb  Nb4  1  0.877  0.651  0.333  1.0
  Sn  Sn5  1  0.805  0.280  0.977  1.0
  Sn  Sn6  1  0.195  0.812  0.055  1.0
  O  O7  1  0.755  0.178  0.567  1.0
  O  O8  1  0.165  0.352  0.442  1.0
  O  O9  1  0.249  0.837  0.431  1.0
  O  O10  1  0.857  0.651  0.562  1.0
  O  O11  1  0.601  0.415  0.291  1.0
  O  O12  1  0.338  0.063  0.711  1.0
  O  O13  1  0.944  0.622  0.141  1.0
  O  O14  1  0.836  0.910  0.861  1.0
  O  O15  1  0.069  0.394  0.853  1.0
  O  O16  1  0.133  0.117  0.150  1.0
  O  O17  1  0.636  0.907  0.296  1.0
  O  O18  1  0.422  0.585  0.705  1.0
[/CIF]
.
The crystal structure described by MgNb4(SnO6)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 3-coordinate geometry to one Sn(2), one O(12), one O(6), and one O(8) atom. There are four inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(1), one O(10), one O(11), one O(2), one O(3), and one O(5) atom to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 29-53°. In the second Nb site, Nb(2) is bonded to one O(1), one O(12), one O(2), one O(4), one O(6), and one O(9) atom to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 32-53°. In the third Nb site, Nb(3) is bonded to one O(1), one O(12), one O(3), one O(4), one O(6), and one O(8) atom to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 32-60°. In the fourth Nb site, Nb(4) is bonded to one O(11), one O(2), one O(3), one O(4), one O(5), and one O(7) atom to form a mixture of distorted corner and edge-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 29-60°. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a rectangular see-saw-like geometry to one O(10), one O(7), one O(8), and one O(9) atom. In the second Sn site, Sn(2) is bonded in a 5-coordinate geometry to one Mg(1), one O(10), one O(11), one O(7), and one O(8) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Nb(1), one Nb(2), and one Nb(3) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Nb(1), one Nb(2), and one Nb(4) atom. In the third O site, O(3) is bonded in a 3-coordinate geometry to one Nb(1), one Nb(3), and one Nb(4) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Nb(2), one Nb(3), and one Nb(4) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Nb(1) and one Nb(4) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Mg(1), one Nb(2), and one Nb(3) atom. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Nb(4), one Sn(1), and one Sn(2) atom. In the eighth O site, O(8) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Nb(3), one Sn(1), and one Sn(2) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Nb(2) and one Sn(1) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Nb(1), one Sn(1), and one Sn(2) atom. In the eleventh O site, O(11) is bonded in a 2-coordinate geometry to one Nb(1), one Nb(4), and one Sn(2) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Mg(1), one Nb(2), and one Nb(3) atom. is represented by the CIF card [CIF]
data_MgNb4(SnO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.146
_cell_length_b   5.722
_cell_length_c   9.495
_cell_angle_alpha   89.486
_cell_angle_beta   110.233
_cell_angle_gamma   90.397
_symmetry_Int_Tables_number   1
_cell_volume   262.345
_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  0.480  0.802  0.870  1.0
  Nb  Nb1  1  0.405  0.164  0.373  1.0
  Nb  Nb2  1  0.128  0.344  0.672  1.0
  Nb  Nb3  1  0.606  0.855  0.610  1.0
  Nb  Nb4  1  0.877  0.651  0.333  1.0
  Sn  Sn5  1  0.805  0.280  0.977  1.0
  Sn  Sn6  1  0.195  0.812  0.055  1.0
  O  O7  1  0.755  0.178  0.567  1.0
  O  O8  1  0.165  0.352  0.442  1.0
  O  O9  1  0.249  0.837  0.431  1.0
  O  O10  1  0.857  0.651  0.562  1.0
  O  O11  1  0.601  0.415  0.291  1.0
  O  O12  1  0.338  0.063  0.711  1.0
  O  O13  1  0.944  0.622  0.141  1.0
  O  O14  1  0.836  0.910  0.861  1.0
  O  O15  1  0.069  0.394  0.853  1.0
  O  O16  1  0.133  0.117  0.150  1.0
  O  O17  1  0.636  0.907  0.296  1.0
  O  O18  1  0.422  0.585  0.705  1.0
[/CIF]
.