The material described by Rb2MgNb2(TeO6)2 crystallizes in the triclinic P1 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 11-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), one O(3), one O(4), one O(6), one O(7), one O(8), and one O(9) atom. In the second Rb site, Rb(2) is bonded in a 3-coordinate geometry to one O(1), one O(3), and one O(6) atom. Mg(1) is bonded in a 4-coordinate geometry to one O(12), one O(5), one O(7), and one O(9) atom. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(10), one O(11), one O(2), one O(4), one O(5), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra and corners with two equivalent Te(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-36°. In the second Nb site, Nb(2) is bonded to one O(12), one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Te(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-37°. There are two inequivalent Te sites. In the first Te site, Te(1) is bonded to one O(1), one O(10), one O(12), one O(4), one O(6), and one O(7) atom to form TeO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-37°. In the second Te site, Te(2) is bonded in a 3-coordinate geometry to one O(1), one O(11), and one O(3) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Rb(1), one Rb(2), one Te(1), and one Te(2) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Nb(1), and one Nb(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Rb(1), one Rb(2), one Nb(2), and one Te(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Nb(1), and one Te(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Nb(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Nb(2), and one Te(1) atom. In the seventh O site, O(7) is bonded in a distorted water-like geometry to one Rb(1), one Mg(1), and one Te(1) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Rb(1), one Nb(1), and one Nb(2) atom. In the ninth O site, O(9) is bonded in a distorted water-like geometry to one Rb(1), one Mg(1), and one Nb(2) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Nb(1), and one Te(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Rb(1), one Nb(1), and one Te(2) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Rb(1), one Mg(1), one Nb(2), and one Te(1) atom. is represented by the CIF card [CIF]
data_Rb2MgNb2(TeO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.577
_cell_length_b   7.649
_cell_length_c   7.444
_cell_angle_alpha   89.948
_cell_angle_beta   61.249
_cell_angle_gamma   120.743
_symmetry_Int_Tables_number   1
_cell_volume   307.172
_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
  Rb  Rb0  1  0.802  0.398  0.386  1.0
  Rb  Rb1  1  0.342  0.789  0.561  1.0
  Mg  Mg2  1  0.056  0.254  0.802  1.0
  Nb  Nb3  1  0.473  0.485  0.970  1.0
  Nb  Nb4  1  0.500  0.002  0.015  1.0
  Te  Te5  1  0.010  0.006  0.493  1.0
  Te  Te6  1  0.923  0.857  0.071  1.0
  O  O7  1  0.799  0.835  0.380  1.0
  O  O8  1  0.540  0.273  0.897  1.0
  O  O9  1  0.183  0.827  0.973  1.0
  O  O10  1  0.167  0.261  0.263  1.0
  O  O11  1  0.311  0.461  0.837  1.0
  O  O12  1  0.229  0.931  0.308  1.0
  O  O13  1  0.216  0.144  0.596  1.0
  O  O14  1  0.439  0.726  0.075  1.0
  O  O15  1  0.743  0.147  0.075  1.0
  O  O16  1  0.821  0.730  0.712  1.0
  O  O17  1  0.674  0.569  0.142  1.0
  O  O18  1  0.797  0.091  0.685  1.0
[/CIF]
.
The material described by Rb2MgNb2(TeO6)2 crystallizes in the triclinic P1 space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 11-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(2), one O(3), one O(4), one O(6), one O(7), one O(8), and one O(9) atom. In the second Rb site, Rb(2) is bonded in a 3-coordinate geometry to one O(1), one O(3), and one O(6) atom. Mg(1) is bonded in a 4-coordinate geometry to one O(12), one O(5), one O(7), and one O(9) atom. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to one O(10), one O(11), one O(2), one O(4), one O(5), and one O(8) atom to form distorted NbO6 octahedra that share corners with two equivalent Nb(2)O6 octahedra and corners with two equivalent Te(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-36°. In the second Nb site, Nb(2) is bonded to one O(12), one O(2), one O(3), one O(6), one O(8), and one O(9) atom to form NbO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Te(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 29-37°. There are two inequivalent Te sites. In the first Te site, Te(1) is bonded to one O(1), one O(10), one O(12), one O(4), one O(6), and one O(7) atom to form TeO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra and corners with two equivalent Nb(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-37°. In the second Te site, Te(2) is bonded in a 3-coordinate geometry to one O(1), one O(11), and one O(3) atom. There are twelve inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Rb(1), one Rb(2), one Te(1), and one Te(2) atom. In the second O site, O(2) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Nb(1), and one Nb(2) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Rb(1), one Rb(2), one Nb(2), and one Te(2) atom. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Nb(1), and one Te(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 150 degrees geometry to one Mg(1) and one Nb(1) atom. In the sixth O site, O(6) is bonded in a 2-coordinate geometry to one Rb(1), one Rb(2), one Nb(2), and one Te(1) atom. In the seventh O site, O(7) is bonded in a distorted water-like geometry to one Rb(1), one Mg(1), and one Te(1) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Rb(1), one Nb(1), and one Nb(2) atom. In the ninth O site, O(9) is bonded in a distorted water-like geometry to one Rb(1), one Mg(1), and one Nb(2) atom. In the tenth O site, O(10) is bonded in a distorted bent 150 degrees geometry to one Rb(1), one Nb(1), and one Te(1) atom. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to one Rb(1), one Nb(1), and one Te(2) atom. In the twelfth O site, O(12) is bonded in a 3-coordinate geometry to one Rb(1), one Mg(1), one Nb(2), and one Te(1) atom. is represented by the CIF card [CIF]
data_Rb2MgNb2(TeO6)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.577
_cell_length_b   7.649
_cell_length_c   7.444
_cell_angle_alpha   89.948
_cell_angle_beta   61.249
_cell_angle_gamma   120.743
_symmetry_Int_Tables_number   1
_cell_volume   307.172
_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
  Rb  Rb0  1  0.802  0.398  0.386  1.0
  Rb  Rb1  1  0.342  0.789  0.561  1.0
  Mg  Mg2  1  0.056  0.254  0.802  1.0
  Nb  Nb3  1  0.473  0.485  0.970  1.0
  Nb  Nb4  1  0.500  0.002  0.015  1.0
  Te  Te5  1  0.010  0.006  0.493  1.0
  Te  Te6  1  0.923  0.857  0.071  1.0
  O  O7  1  0.799  0.835  0.380  1.0
  O  O8  1  0.540  0.273  0.897  1.0
  O  O9  1  0.183  0.827  0.973  1.0
  O  O10  1  0.167  0.261  0.263  1.0
  O  O11  1  0.311  0.461  0.837  1.0
  O  O12  1  0.229  0.931  0.308  1.0
  O  O13  1  0.216  0.144  0.596  1.0
  O  O14  1  0.439  0.726  0.075  1.0
  O  O15  1  0.743  0.147  0.075  1.0
  O  O16  1  0.821  0.730  0.712  1.0
  O  O17  1  0.674  0.569  0.142  1.0
  O  O18  1  0.797  0.091  0.685  1.0
[/CIF]
.