The material described by MgNb4(SnO6)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(11), one O(2), one O(3), one O(4), and one O(6) atom to form MgO6 octahedra that share edges with two equivalent Nb(1)O6 octahedra and edges with two equivalent Nb(3)O6 octahedra. 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 NbO6 octahedra that share  an edgeedge with one Nb(3)O6 octahedra and edges with two equivalent Mg(1)O6 octahedra. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one O(1), one O(12), one O(2), one O(4), one O(6), and one O(9) atom. 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 NbO6 octahedra that share  an edgeedge with one Nb(1)O6 octahedra and edges with two equivalent Mg(1)O6 octahedra. In the fourth Nb site, Nb(4) is bonded in a 6-coordinate geometry to one O(11), one O(2), one O(3), one O(4), one O(5), and one O(7) atom. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a distorted 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 distorted rectangular see-saw-like geometry to one O(10), one O(7), one O(8), and one O(9) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Nb(1), one Nb(2), and one Nb(3) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Nb(1), one Nb(2), and one Nb(4) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Nb(1), one Nb(3), and one Nb(4) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), 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 T-shaped geometry to one Mg(1), one Nb(2), and one Nb(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate 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 trigonal planar geometry to one Nb(3), one Sn(1), and one Sn(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Nb(2), one Sn(1), and one Sn(2) 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 T-shaped geometry to one Mg(1), one Nb(1), and one Nb(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Nb(2) and one Nb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgNb4(SnO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.085
_cell_length_b   5.664
_cell_length_c   9.496
_cell_angle_alpha   89.115
_cell_angle_beta   107.724
_cell_angle_gamma   89.886
_symmetry_Int_Tables_number   1
_cell_volume   260.495
_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  0.001  0.998  0.503  1.0
  Nb  Nb1  1  0.413  0.133  0.341  1.0
  Nb  Nb2  1  0.083  0.389  0.683  1.0
  Nb  Nb3  1  0.589  0.861  0.665  1.0
  Nb  Nb4  1  0.919  0.606  0.323  1.0
  Sn  Sn5  1  0.780  0.236  0.996  1.0
  Sn  Sn6  1  0.224  0.758  0.011  1.0
  O  O7  1  0.725  0.168  0.567  1.0
  O  O8  1  0.144  0.319  0.431  1.0
  O  O9  1  0.276  0.825  0.439  1.0
  O  O10  1  0.857  0.674  0.575  1.0
  O  O11  1  0.597  0.409  0.289  1.0
  O  O12  1  0.299  0.083  0.696  1.0
  O  O13  1  0.975  0.586  0.136  1.0
  O  O14  1  0.847  0.915  0.860  1.0
  O  O15  1  0.030  0.408  0.870  1.0
  O  O16  1  0.157  0.079  0.146  1.0
  O  O17  1  0.703  0.910  0.309  1.0
  O  O18  1  0.405  0.585  0.718  1.0
[/CIF]
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The material described by MgNb4(SnO6)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(11), one O(2), one O(3), one O(4), and one O(6) atom to form MgO6 octahedra that share edges with two equivalent Nb(1)O6 octahedra and edges with two equivalent Nb(3)O6 octahedra. 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 NbO6 octahedra that share  an edgeedge with one Nb(3)O6 octahedra and edges with two equivalent Mg(1)O6 octahedra. In the second Nb site, Nb(2) is bonded in a 6-coordinate geometry to one O(1), one O(12), one O(2), one O(4), one O(6), and one O(9) atom. 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 NbO6 octahedra that share  an edgeedge with one Nb(1)O6 octahedra and edges with two equivalent Mg(1)O6 octahedra. In the fourth Nb site, Nb(4) is bonded in a 6-coordinate geometry to one O(11), one O(2), one O(3), one O(4), one O(5), and one O(7) atom. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a distorted 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 distorted rectangular see-saw-like geometry to one O(10), one O(7), one O(8), and one O(9) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Nb(1), one Nb(2), and one Nb(3) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Mg(1), one Nb(1), one Nb(2), and one Nb(4) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Nb(1), one Nb(3), and one Nb(4) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Mg(1), 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 T-shaped geometry to one Mg(1), one Nb(2), and one Nb(3) atom. In the seventh O site, O(7) is bonded in a 3-coordinate 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 trigonal planar geometry to one Nb(3), one Sn(1), and one Sn(2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Nb(2), one Sn(1), and one Sn(2) 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 T-shaped geometry to one Mg(1), one Nb(1), and one Nb(4) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Nb(2) and one Nb(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgNb4(SnO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.085
_cell_length_b   5.664
_cell_length_c   9.496
_cell_angle_alpha   89.115
_cell_angle_beta   107.724
_cell_angle_gamma   89.886
_symmetry_Int_Tables_number   1
_cell_volume   260.495
_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  0.001  0.998  0.503  1.0
  Nb  Nb1  1  0.413  0.133  0.341  1.0
  Nb  Nb2  1  0.083  0.389  0.683  1.0
  Nb  Nb3  1  0.589  0.861  0.665  1.0
  Nb  Nb4  1  0.919  0.606  0.323  1.0
  Sn  Sn5  1  0.780  0.236  0.996  1.0
  Sn  Sn6  1  0.224  0.758  0.011  1.0
  O  O7  1  0.725  0.168  0.567  1.0
  O  O8  1  0.144  0.319  0.431  1.0
  O  O9  1  0.276  0.825  0.439  1.0
  O  O10  1  0.857  0.674  0.575  1.0
  O  O11  1  0.597  0.409  0.289  1.0
  O  O12  1  0.299  0.083  0.696  1.0
  O  O13  1  0.975  0.586  0.136  1.0
  O  O14  1  0.847  0.915  0.860  1.0
  O  O15  1  0.030  0.408  0.870  1.0
  O  O16  1  0.157  0.079  0.146  1.0
  O  O17  1  0.703  0.910  0.309  1.0
  O  O18  1  0.405  0.585  0.718  1.0
[/CIF]
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