The crystal structure described by SrBi2Ta2O9 crystallizes in the orthorhombic Cmc2_1 space group. Sr(1) is bonded in a 12-coordinate geometry to four equivalent O(1), four equivalent O(2), and four equivalent O(4) atoms. Ta(1) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 11-23°. Bi(1) is bonded in a 6-coordinate geometry to two equivalent O(5) and four equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted single-bond geometry to one Ta(1) and two equivalent Bi(1) atoms. In the second O site, O(1) is bonded in a distorted linear geometry to two equivalent Sr(1) and two equivalent Ta(1) atoms. In the third O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Sr(1) and two equivalent Ta(1) atoms. In the fourth O site, O(3) is bonded to four equivalent Bi(1) atoms to form a mixture of corner and edge-sharing OBi4 tetrahedra. In the fifth O site, O(4) is bonded in a 6-coordinate geometry to four equivalent Sr(1) and two equivalent Ta(1) atoms. is represented by the CIF card [CIF]
data_SrTa2Bi2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.538
_cell_length_b   5.535
_cell_length_c   12.810
_cell_angle_alpha   102.478
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   383.394
_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
  Sr  Sr0  1  0.014  0.749  0.000  1.0
  Sr  Sr1  1  0.514  0.251  0.000  1.0
  Ta  Ta2  1  0.018  0.332  0.168  1.0
  Ta  Ta3  1  0.518  0.836  0.168  1.0
  Ta  Ta4  1  0.018  0.164  0.832  1.0
  Ta  Ta5  1  0.518  0.668  0.832  1.0
  Bi  Bi6  1  0.935  0.979  0.400  1.0
  Bi  Bi7  1  0.435  0.021  0.600  1.0
  Bi  Bi8  1  0.435  0.420  0.400  1.0
  Bi  Bi9  1  0.935  0.580  0.600  1.0
  O  O10  1  0.797  0.603  0.169  1.0
  O  O11  1  0.297  0.397  0.831  1.0
  O  O12  1  0.297  0.566  0.169  1.0
  O  O13  1  0.797  0.434  0.831  1.0
  O  O14  1  0.770  0.080  0.136  1.0
  O  O15  1  0.270  0.920  0.864  1.0
  O  O16  1  0.270  0.056  0.136  1.0
  O  O17  1  0.770  0.944  0.864  1.0
  O  O18  1  0.717  0.266  0.502  1.0
  O  O19  1  0.217  0.734  0.498  1.0
  O  O20  1  0.535  0.705  0.000  1.0
  O  O21  1  0.035  0.295  0.000  1.0
  O  O22  1  0.537  0.975  0.315  1.0
  O  O23  1  0.037  0.025  0.685  1.0
  O  O24  1  0.037  0.339  0.315  1.0
  O  O25  1  0.537  0.661  0.685  1.0
  O  O26  1  0.717  0.764  0.498  1.0
  O  O27  1  0.217  0.236  0.502  1.0
[/CIF]
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The crystal structure described by SrBi2Ta2O9 crystallizes in the orthorhombic Cmc2_1 space group. Sr(1) is bonded in a 12-coordinate geometry to four equivalent O(1), four equivalent O(2), and four equivalent O(4) atoms. Ta(1) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 11-23°. Bi(1) is bonded in a 6-coordinate geometry to two equivalent O(5) and four equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(5) is bonded in a distorted single-bond geometry to one Ta(1) and two equivalent Bi(1) atoms. In the second O site, O(1) is bonded in a distorted linear geometry to two equivalent Sr(1) and two equivalent Ta(1) atoms. In the third O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Sr(1) and two equivalent Ta(1) atoms. In the fourth O site, O(3) is bonded to four equivalent Bi(1) atoms to form a mixture of corner and edge-sharing OBi4 tetrahedra. In the fifth O site, O(4) is bonded in a 6-coordinate geometry to four equivalent Sr(1) and two equivalent Ta(1) atoms. is represented by the CIF card [CIF]
data_SrTa2Bi2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.538
_cell_length_b   5.535
_cell_length_c   12.810
_cell_angle_alpha   102.478
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   383.394
_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
  Sr  Sr0  1  0.014  0.749  0.000  1.0
  Sr  Sr1  1  0.514  0.251  0.000  1.0
  Ta  Ta2  1  0.018  0.332  0.168  1.0
  Ta  Ta3  1  0.518  0.836  0.168  1.0
  Ta  Ta4  1  0.018  0.164  0.832  1.0
  Ta  Ta5  1  0.518  0.668  0.832  1.0
  Bi  Bi6  1  0.935  0.979  0.400  1.0
  Bi  Bi7  1  0.435  0.021  0.600  1.0
  Bi  Bi8  1  0.435  0.420  0.400  1.0
  Bi  Bi9  1  0.935  0.580  0.600  1.0
  O  O10  1  0.797  0.603  0.169  1.0
  O  O11  1  0.297  0.397  0.831  1.0
  O  O12  1  0.297  0.566  0.169  1.0
  O  O13  1  0.797  0.434  0.831  1.0
  O  O14  1  0.770  0.080  0.136  1.0
  O  O15  1  0.270  0.920  0.864  1.0
  O  O16  1  0.270  0.056  0.136  1.0
  O  O17  1  0.770  0.944  0.864  1.0
  O  O18  1  0.717  0.266  0.502  1.0
  O  O19  1  0.217  0.734  0.498  1.0
  O  O20  1  0.535  0.705  0.000  1.0
  O  O21  1  0.035  0.295  0.000  1.0
  O  O22  1  0.537  0.975  0.315  1.0
  O  O23  1  0.037  0.025  0.685  1.0
  O  O24  1  0.037  0.339  0.315  1.0
  O  O25  1  0.537  0.661  0.685  1.0
  O  O26  1  0.717  0.764  0.498  1.0
  O  O27  1  0.217  0.236  0.502  1.0
[/CIF]
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