The compound described by Rb3MgNbO8 crystallizes in the monoclinic Cm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(5), one O(6), two equivalent O(1), and two equivalent O(4) atoms. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to one O(3), one O(4), one O(6), and two equivalent O(1) atoms. Mg(1) is bonded in a 5-coordinate geometry to one O(2), one O(5), one O(6), and two equivalent O(1) atoms. Nb(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(5), one O(6), two equivalent O(1), and two equivalent O(4) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Rb(1), two equivalent Rb(2), one Mg(1), one Nb(1), and one O(4) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Rb(1), one Mg(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Rb(1), two equivalent Rb(2), one Nb(1), and one O(5) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Rb(1), one Rb(2), one Nb(1), and one O(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Rb(1), one Mg(1), one Nb(1), and one O(3) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Rb(1), two equivalent Rb(2), one Mg(1), and one Nb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb3MgNbO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.921
_cell_length_b   7.281
_cell_length_c   5.970
_cell_angle_alpha   98.523
_cell_angle_beta   110.692
_cell_angle_gamma   117.518
_symmetry_Int_Tables_number   1
_cell_volume   231.350
_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  0.000  0.465  0.508  1.0
  Rb  Rb1  1  0.413  0.755  0.238  1.0
  Rb  Rb2  1  0.587  0.342  0.825  1.0
  Mg  Mg3  1  0.000  0.926  0.554  1.0
  Nb  Nb4  1  0.000  0.981  0.054  1.0
  O  O5  1  0.250  0.953  0.909  1.0
  O  O6  1  0.000  0.113  0.359  1.0
  O  O7  1  0.000  0.257  0.022  1.0
  O  O8  1  0.750  0.703  0.659  1.0
  O  O9  1  0.622  0.778  0.771  1.0
  O  O10  1  0.000  0.183  0.779  1.0
  O  O11  1  0.000  0.770  0.233  1.0
  O  O12  1  0.378  0.156  0.149  1.0
[/CIF]
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The compound described by Rb3MgNbO8 crystallizes in the monoclinic Cm space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(5), one O(6), two equivalent O(1), and two equivalent O(4) atoms. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to one O(3), one O(4), one O(6), and two equivalent O(1) atoms. Mg(1) is bonded in a 5-coordinate geometry to one O(2), one O(5), one O(6), and two equivalent O(1) atoms. Nb(1) is bonded in a 8-coordinate geometry to one O(2), one O(3), one O(5), one O(6), two equivalent O(1), and two equivalent O(4) atoms. There are six inequivalent O sites. In the first O site, O(1) is bonded in a 6-coordinate geometry to one Rb(1), two equivalent Rb(2), one Mg(1), one Nb(1), and one O(4) atom. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Rb(1), one Mg(1), and one Nb(1) atom. In the third O site, O(3) is bonded in a 5-coordinate geometry to one Rb(1), two equivalent Rb(2), one Nb(1), and one O(5) atom. In the fourth O site, O(4) is bonded in a 1-coordinate geometry to one Rb(1), one Rb(2), one Nb(1), and one O(1) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Rb(1), one Mg(1), one Nb(1), and one O(3) atom. In the sixth O site, O(6) is bonded in a 5-coordinate geometry to one Rb(1), two equivalent Rb(2), one Mg(1), and one Nb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Rb3MgNbO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.921
_cell_length_b   7.281
_cell_length_c   5.970
_cell_angle_alpha   98.523
_cell_angle_beta   110.692
_cell_angle_gamma   117.518
_symmetry_Int_Tables_number   1
_cell_volume   231.350
_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  0.000  0.465  0.508  1.0
  Rb  Rb1  1  0.413  0.755  0.238  1.0
  Rb  Rb2  1  0.587  0.342  0.825  1.0
  Mg  Mg3  1  0.000  0.926  0.554  1.0
  Nb  Nb4  1  0.000  0.981  0.054  1.0
  O  O5  1  0.250  0.953  0.909  1.0
  O  O6  1  0.000  0.113  0.359  1.0
  O  O7  1  0.000  0.257  0.022  1.0
  O  O8  1  0.750  0.703  0.659  1.0
  O  O9  1  0.622  0.778  0.771  1.0
  O  O10  1  0.000  0.183  0.779  1.0
  O  O11  1  0.000  0.770  0.233  1.0
  O  O12  1  0.378  0.156  0.149  1.0
[/CIF]
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