The compound described by RbTaO3 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the monoclinic C2/m 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(1), one O(3), two equivalent O(4), and four equivalent O(2) atoms. In the second Rb site, Rb(2) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(4) atoms. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form a mixture of corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 4°. In the second Ta site, Ta(2) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form a mixture of distorted corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Rb(1), one Ta(2), and two equivalent Ta(1) atoms to form edge-sharing ORbTa3 trigonal pyramids. In the second O site, O(2) is bonded in a linear geometry to two equivalent Rb(1), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Ta(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Rb(1), one Rb(2), one Ta(1), and one Ta(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbTaO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.430
_cell_length_b   6.430
_cell_length_c   8.168
_cell_angle_alpha   86.248
_cell_angle_beta   86.248
_cell_angle_gamma   83.071
_symmetry_Int_Tables_number   1
_cell_volume   333.986
_cell_formula_units_Z   4
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  0.662  0.662  0.761  1.0
  Rb  Rb1  1  0.338  0.338  0.239  1.0
  Rb  Rb2  1  0.234  0.766  0.500  1.0
  Rb  Rb3  1  0.766  0.234  0.500  1.0
  Ta  Ta4  1  0.189  0.811  0.000  1.0
  Ta  Ta5  1  0.811  0.189  0.000  1.0
  Ta  Ta6  1  0.739  0.739  0.196  1.0
  Ta  Ta7  1  0.261  0.261  0.804  1.0
  O  O8  1  0.123  0.123  0.052  1.0
  O  O9  1  0.877  0.877  0.948  1.0
  O  O10  1  0.773  0.453  0.103  1.0
  O  O11  1  0.547  0.227  0.897  1.0
  O  O12  1  0.227  0.547  0.897  1.0
  O  O13  1  0.453  0.773  0.103  1.0
  O  O14  1  0.331  0.331  0.590  1.0
  O  O15  1  0.669  0.669  0.410  1.0
  O  O16  1  0.287  0.952  0.789  1.0
  O  O17  1  0.048  0.713  0.211  1.0
  O  O18  1  0.713  0.048  0.211  1.0
  O  O19  1  0.952  0.287  0.789  1.0
[/CIF]
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The compound described by RbTaO3 is Pb(Zr_(1-x)Ti_x)O3-like structured and crystallizes in the monoclinic C2/m 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(1), one O(3), two equivalent O(4), and four equivalent O(2) atoms. In the second Rb site, Rb(2) is bonded in a 4-coordinate geometry to two equivalent O(3) and two equivalent O(4) atoms. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form a mixture of corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 4°. In the second Ta site, Ta(2) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form a mixture of distorted corner and edge-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Rb(1), one Ta(2), and two equivalent Ta(1) atoms to form edge-sharing ORbTa3 trigonal pyramids. In the second O site, O(2) is bonded in a linear geometry to two equivalent Rb(1), one Ta(1), and one Ta(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Rb(1), two equivalent Rb(2), and one Ta(2) atom. In the fourth O site, O(4) is bonded in a 4-coordinate geometry to one Rb(1), one Rb(2), one Ta(1), and one Ta(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_RbTaO3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.430
_cell_length_b   6.430
_cell_length_c   8.168
_cell_angle_alpha   86.248
_cell_angle_beta   86.248
_cell_angle_gamma   83.071
_symmetry_Int_Tables_number   1
_cell_volume   333.986
_cell_formula_units_Z   4
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  0.662  0.662  0.761  1.0
  Rb  Rb1  1  0.338  0.338  0.239  1.0
  Rb  Rb2  1  0.234  0.766  0.500  1.0
  Rb  Rb3  1  0.766  0.234  0.500  1.0
  Ta  Ta4  1  0.189  0.811  0.000  1.0
  Ta  Ta5  1  0.811  0.189  0.000  1.0
  Ta  Ta6  1  0.739  0.739  0.196  1.0
  Ta  Ta7  1  0.261  0.261  0.804  1.0
  O  O8  1  0.123  0.123  0.052  1.0
  O  O9  1  0.877  0.877  0.948  1.0
  O  O10  1  0.773  0.453  0.103  1.0
  O  O11  1  0.547  0.227  0.897  1.0
  O  O12  1  0.227  0.547  0.897  1.0
  O  O13  1  0.453  0.773  0.103  1.0
  O  O14  1  0.331  0.331  0.590  1.0
  O  O15  1  0.669  0.669  0.410  1.0
  O  O16  1  0.287  0.952  0.789  1.0
  O  O17  1  0.048  0.713  0.211  1.0
  O  O18  1  0.713  0.048  0.211  1.0
  O  O19  1  0.952  0.287  0.789  1.0
[/CIF]
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