The crystal structure described by Rb2Ta2O5 crystallizes in the orthorhombic Imma 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 Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second Ta site, Ta(2) is bonded in a rectangular 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 Ta(1) atoms to form a mixture of distorted edge, face, and corner-sharing ORb4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the second O site, O(2) is bonded to four equivalent Rb(1), one Ta(1), and one Ta(2) atom to form a mixture of distorted edge, face, and corner-sharing ORb4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Rb(1) and two equivalent Ta(2) atoms. is represented by the CIF card [CIF]
data_Rb2Ta2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.080
_cell_length_b   9.080
_cell_length_c   9.080
_cell_angle_alpha   142.424
_cell_angle_beta   142.166
_cell_angle_gamma   54.385
_symmetry_Int_Tables_number   1
_cell_volume   278.084
_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  0.622  0.114  0.492  1.0
  Rb  Rb1  1  0.378  0.886  0.508  1.0
  Rb  Rb2  1  0.122  0.630  0.508  1.0
  Rb  Rb3  1  0.878  0.370  0.492  1.0
  Ta  Ta4  1  0.000  0.000  0.000  1.0
  Ta  Ta5  1  0.500  0.500  0.000  1.0
  Ta  Ta6  1  0.250  0.283  0.033  1.0
  Ta  Ta7  1  0.750  0.717  0.967  1.0
  O  O8  1  0.249  0.749  0.000  1.0
  O  O9  1  0.251  0.251  0.500  1.0
  O  O10  1  0.749  0.749  0.500  1.0
  O  O11  1  0.751  0.251  0.000  1.0
  O  O12  1  0.128  0.125  0.996  1.0
  O  O13  1  0.872  0.875  0.004  1.0
  O  O14  1  0.628  0.632  0.004  1.0
  O  O15  1  0.372  0.368  0.996  1.0
  O  O16  1  0.000  0.500  0.000  1.0
  O  O17  1  0.500  0.500  0.500  1.0
[/CIF]
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The crystal structure described by Rb2Ta2O5 crystallizes in the orthorhombic Imma 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 Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second Ta site, Ta(2) is bonded in a rectangular 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 Ta(1) atoms to form a mixture of distorted edge, face, and corner-sharing ORb4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the second O site, O(2) is bonded to four equivalent Rb(1), one Ta(1), and one Ta(2) atom to form a mixture of distorted edge, face, and corner-sharing ORb4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 0-59°. In the third O site, O(3) is bonded in a distorted linear geometry to four equivalent Rb(1) and two equivalent Ta(2) atoms. is represented by the CIF card [CIF]
data_Rb2Ta2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.080
_cell_length_b   9.080
_cell_length_c   9.080
_cell_angle_alpha   142.424
_cell_angle_beta   142.166
_cell_angle_gamma   54.385
_symmetry_Int_Tables_number   1
_cell_volume   278.084
_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  0.622  0.114  0.492  1.0
  Rb  Rb1  1  0.378  0.886  0.508  1.0
  Rb  Rb2  1  0.122  0.630  0.508  1.0
  Rb  Rb3  1  0.878  0.370  0.492  1.0
  Ta  Ta4  1  0.000  0.000  0.000  1.0
  Ta  Ta5  1  0.500  0.500  0.000  1.0
  Ta  Ta6  1  0.250  0.283  0.033  1.0
  Ta  Ta7  1  0.750  0.717  0.967  1.0
  O  O8  1  0.249  0.749  0.000  1.0
  O  O9  1  0.251  0.251  0.500  1.0
  O  O10  1  0.749  0.749  0.500  1.0
  O  O11  1  0.751  0.251  0.000  1.0
  O  O12  1  0.128  0.125  0.996  1.0
  O  O13  1  0.872  0.875  0.004  1.0
  O  O14  1  0.628  0.632  0.004  1.0
  O  O15  1  0.372  0.368  0.996  1.0
  O  O16  1  0.000  0.500  0.000  1.0
  O  O17  1  0.500  0.500  0.500  1.0
[/CIF]
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