The material described by Rb2Nb2O5 crystallizes in the orthorhombic Ima2 space group. Rb(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 6°. In the second Nb site, Nb(2) is bonded in a distorted see-saw-like geometry to two equivalent O(2) and two equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Rb(1) and two equivalent Nb(1) atoms to form a mixture of distorted edge, corner, and face-sharing ORb4Nb2 octahedra. The corner-sharing octahedral tilt angles are 6°. In the second O site, O(2) is bonded in a 2-coordinate geometry to four equivalent Rb(1), one Nb(1), and one Nb(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Rb(1) and two equivalent Nb(2) atoms. is represented by the CIF card [CIF]
data_Rb2Nb2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.141
_cell_length_b   9.141
_cell_length_c   9.141
_cell_angle_alpha   141.649
_cell_angle_beta   141.461
_cell_angle_gamma   55.500
_symmetry_Int_Tables_number   1
_cell_volume   293.064
_cell_formula_units_Z   2
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  0.384  0.872  0.498  1.0
  Rb  Rb1  1  0.626  0.128  0.512  1.0
  Rb  Rb2  1  0.884  0.386  0.512  1.0
  Rb  Rb3  1  0.126  0.614  0.498  1.0
  Nb  Nb4  1  0.985  0.000  0.985  1.0
  Nb  Nb5  1  0.485  0.500  0.985  1.0
  Nb  Nb6  1  0.764  0.793  0.057  1.0
  Nb  Nb7  1  0.264  0.207  0.971  1.0
  O  O8  1  0.774  0.762  0.530  1.0
  O  O9  1  0.768  0.238  0.011  1.0
  O  O10  1  0.274  0.743  0.011  1.0
  O  O11  1  0.268  0.257  0.530  1.0
  O  O12  1  0.882  0.860  0.999  1.0
  O  O13  1  0.140  0.140  0.023  1.0
  O  O14  1  0.382  0.383  0.023  1.0
  O  O15  1  0.640  0.617  0.999  1.0
  O  O16  1  0.012  0.002  0.514  1.0
  O  O17  1  0.512  0.998  0.011  1.0
[/CIF]
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The material described by Rb2Nb2O5 crystallizes in the orthorhombic Ima2 space group. Rb(1) is bonded in a 10-coordinate geometry to two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles are 6°. In the second Nb site, Nb(2) is bonded in a distorted see-saw-like geometry to two equivalent O(2) and two equivalent O(3) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Rb(1) and two equivalent Nb(1) atoms to form a mixture of distorted edge, corner, and face-sharing ORb4Nb2 octahedra. The corner-sharing octahedral tilt angles are 6°. In the second O site, O(2) is bonded in a 2-coordinate geometry to four equivalent Rb(1), one Nb(1), and one Nb(2) atom. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Rb(1) and two equivalent Nb(2) atoms. is represented by the CIF card [CIF]
data_Rb2Nb2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.141
_cell_length_b   9.141
_cell_length_c   9.141
_cell_angle_alpha   141.649
_cell_angle_beta   141.461
_cell_angle_gamma   55.500
_symmetry_Int_Tables_number   1
_cell_volume   293.064
_cell_formula_units_Z   2
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  0.384  0.872  0.498  1.0
  Rb  Rb1  1  0.626  0.128  0.512  1.0
  Rb  Rb2  1  0.884  0.386  0.512  1.0
  Rb  Rb3  1  0.126  0.614  0.498  1.0
  Nb  Nb4  1  0.985  0.000  0.985  1.0
  Nb  Nb5  1  0.485  0.500  0.985  1.0
  Nb  Nb6  1  0.764  0.793  0.057  1.0
  Nb  Nb7  1  0.264  0.207  0.971  1.0
  O  O8  1  0.774  0.762  0.530  1.0
  O  O9  1  0.768  0.238  0.011  1.0
  O  O10  1  0.274  0.743  0.011  1.0
  O  O11  1  0.268  0.257  0.530  1.0
  O  O12  1  0.882  0.860  0.999  1.0
  O  O13  1  0.140  0.140  0.023  1.0
  O  O14  1  0.382  0.383  0.023  1.0
  O  O15  1  0.640  0.617  0.999  1.0
  O  O16  1  0.012  0.002  0.514  1.0
  O  O17  1  0.512  0.998  0.011  1.0
[/CIF]
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