The compound described by Rb2LaNb2O8 crystallizes in the tetragonal P4/mmm space group. Rb(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. La(1) is bonded to four equivalent O(3) and eight equivalent O(4) atoms to form a mixture of face and corner-sharing LaO12 cuboctahedra. Nb(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), and four equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a body-centered cubic geometry to eight equivalent Rb(1) atoms. In the second O site, O(2) is bonded in a single-bond geometry to four equivalent Rb(1) and one Nb(1) atom. In the third O site, O(3) is bonded to four equivalent La(1) and two equivalent Nb(1) atoms to form a mixture of corner and edge-sharing OLa4Nb2 octahedra. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to two equivalent La(1) and two equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Rb2LaNb2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.917
_cell_length_b   3.917
_cell_length_c   14.842
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   227.720
_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  0.000  0.615  1.0
  Rb  Rb1  1  0.000  0.000  0.385  1.0
  La  La2  1  0.000  0.000  0.000  1.0
  Nb  Nb3  1  0.500  0.500  0.845  1.0
  Nb  Nb4  1  0.500  0.500  0.155  1.0
  O  O5  1  0.500  0.500  0.500  1.0
  O  O6  1  0.500  0.500  0.723  1.0
  O  O7  1  0.500  0.500  0.277  1.0
  O  O8  1  0.500  0.500  0.000  1.0
  O  O9  1  0.500  0.000  0.875  1.0
  O  O10  1  0.000  0.500  0.875  1.0
  O  O11  1  0.500  0.000  0.125  1.0
  O  O12  1  0.000  0.500  0.125  1.0
[/CIF]
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The compound described by Rb2LaNb2O8 crystallizes in the tetragonal P4/mmm space group. Rb(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. La(1) is bonded to four equivalent O(3) and eight equivalent O(4) atoms to form a mixture of face and corner-sharing LaO12 cuboctahedra. Nb(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), and four equivalent O(4) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a body-centered cubic geometry to eight equivalent Rb(1) atoms. In the second O site, O(2) is bonded in a single-bond geometry to four equivalent Rb(1) and one Nb(1) atom. In the third O site, O(3) is bonded to four equivalent La(1) and two equivalent Nb(1) atoms to form a mixture of corner and edge-sharing OLa4Nb2 octahedra. The corner-sharing octahedra are not tilted. In the fourth O site, O(4) is bonded in a distorted bent 150 degrees geometry to two equivalent La(1) and two equivalent Nb(1) atoms. is represented by the CIF card [CIF]
data_Rb2LaNb2O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.917
_cell_length_b   3.917
_cell_length_c   14.842
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   227.720
_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  0.000  0.615  1.0
  Rb  Rb1  1  0.000  0.000  0.385  1.0
  La  La2  1  0.000  0.000  0.000  1.0
  Nb  Nb3  1  0.500  0.500  0.845  1.0
  Nb  Nb4  1  0.500  0.500  0.155  1.0
  O  O5  1  0.500  0.500  0.500  1.0
  O  O6  1  0.500  0.500  0.723  1.0
  O  O7  1  0.500  0.500  0.277  1.0
  O  O8  1  0.500  0.500  0.000  1.0
  O  O9  1  0.500  0.000  0.875  1.0
  O  O10  1  0.000  0.500  0.875  1.0
  O  O11  1  0.500  0.000  0.125  1.0
  O  O12  1  0.000  0.500  0.125  1.0
[/CIF]
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