The structure described by Na4Tb2(IrO4)3 crystallizes in the hexagonal P-62m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(2), and four equivalent O(3) atoms. In the second Na site, Na(2) is bonded to six equivalent O(2) atoms to form distorted NaO6 pentagonal pyramids that share corners with six equivalent Ir(1)O6 octahedra, edges with three equivalent Ir(1)O6 octahedra, and faces with two equivalent Na(2)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 11°. Tb(1) is bonded in a 9-coordinate geometry to three equivalent O(1) and six equivalent O(3) atoms. Ir(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form IrO6 octahedra that share corners with two equivalent Na(2)O6 pentagonal pyramids, edges with two equivalent Ir(1)O6 octahedra, and  an edgeedge with one Na(2)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Tb(1), and two equivalent Ir(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Ir(1) atoms to form ONa4Ir2 octahedra that share corners with four equivalent O(2)Na4Ir2 octahedra, corners with four equivalent O(3)Na2Tb2Ir trigonal bipyramids, edges with two equivalent O(2)Na4Ir2 octahedra, edges with four equivalent O(3)Na2Tb2Ir trigonal bipyramids, and faces with two equivalent O(2)Na4Ir2 octahedra. The corner-sharing octahedral tilt angles are 45°. In the third O site, O(3) is bonded to two equivalent Na(1), two equivalent Tb(1), and one Ir(1) atom to form distorted ONa2Tb2Ir trigonal bipyramids that share corners with two equivalent O(2)Na4Ir2 octahedra, corners with seven equivalent O(3)Na2Tb2Ir trigonal bipyramids, edges with two equivalent O(2)Na4Ir2 octahedra, and edges with five equivalent O(3)Na2Tb2Ir trigonal bipyramids. The corner-sharing octahedral tilt angles are 52°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4Tb2(IrO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.208
_cell_length_b   9.481
_cell_length_c   9.481
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   249.718
_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
  Na  Na0  1  0.500  0.301  0.301  1.0
  Na  Na1  1  0.500  0.000  0.699  1.0
  Na  Na2  1  0.500  0.699  0.000  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Tb  Tb4  1  0.500  0.667  0.333  1.0
  Tb  Tb5  1  0.500  0.333  0.667  1.0
  Ir  Ir6  1  0.000  0.670  0.670  1.0
  Ir  Ir7  1  0.000  0.000  0.330  1.0
  Ir  Ir8  1  0.000  0.330  0.000  1.0
  O  O9  1  0.500  0.544  0.544  1.0
  O  O10  1  0.500  0.000  0.456  1.0
  O  O11  1  0.500  0.456  0.000  1.0
  O  O12  1  0.500  0.803  0.803  1.0
  O  O13  1  0.500  0.000  0.197  1.0
  O  O14  1  0.500  0.197  0.000  1.0
  O  O15  1  0.000  0.757  0.216  1.0
  O  O16  1  0.000  0.460  0.243  1.0
  O  O17  1  0.000  0.540  0.784  1.0
  O  O18  1  0.000  0.784  0.540  1.0
  O  O19  1  0.000  0.216  0.757  1.0
  O  O20  1  0.000  0.243  0.460  1.0
[/CIF]
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The structure described by Na4Tb2(IrO4)3 crystallizes in the hexagonal P-62m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to one O(1), two equivalent O(2), and four equivalent O(3) atoms. In the second Na site, Na(2) is bonded to six equivalent O(2) atoms to form distorted NaO6 pentagonal pyramids that share corners with six equivalent Ir(1)O6 octahedra, edges with three equivalent Ir(1)O6 octahedra, and faces with two equivalent Na(2)O6 pentagonal pyramids. The corner-sharing octahedral tilt angles are 11°. Tb(1) is bonded in a 9-coordinate geometry to three equivalent O(1) and six equivalent O(3) atoms. Ir(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form IrO6 octahedra that share corners with two equivalent Na(2)O6 pentagonal pyramids, edges with two equivalent Ir(1)O6 octahedra, and  an edgeedge with one Na(2)O6 pentagonal pyramid. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to one Na(1), two equivalent Tb(1), and two equivalent Ir(1) atoms. In the second O site, O(2) is bonded to two equivalent Na(1), two equivalent Na(2), and two equivalent Ir(1) atoms to form ONa4Ir2 octahedra that share corners with four equivalent O(2)Na4Ir2 octahedra, corners with four equivalent O(3)Na2Tb2Ir trigonal bipyramids, edges with two equivalent O(2)Na4Ir2 octahedra, edges with four equivalent O(3)Na2Tb2Ir trigonal bipyramids, and faces with two equivalent O(2)Na4Ir2 octahedra. The corner-sharing octahedral tilt angles are 45°. In the third O site, O(3) is bonded to two equivalent Na(1), two equivalent Tb(1), and one Ir(1) atom to form distorted ONa2Tb2Ir trigonal bipyramids that share corners with two equivalent O(2)Na4Ir2 octahedra, corners with seven equivalent O(3)Na2Tb2Ir trigonal bipyramids, edges with two equivalent O(2)Na4Ir2 octahedra, and edges with five equivalent O(3)Na2Tb2Ir trigonal bipyramids. The corner-sharing octahedral tilt angles are 52°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4Tb2(IrO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.208
_cell_length_b   9.481
_cell_length_c   9.481
_cell_angle_alpha   120.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   249.718
_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
  Na  Na0  1  0.500  0.301  0.301  1.0
  Na  Na1  1  0.500  0.000  0.699  1.0
  Na  Na2  1  0.500  0.699  0.000  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Tb  Tb4  1  0.500  0.667  0.333  1.0
  Tb  Tb5  1  0.500  0.333  0.667  1.0
  Ir  Ir6  1  0.000  0.670  0.670  1.0
  Ir  Ir7  1  0.000  0.000  0.330  1.0
  Ir  Ir8  1  0.000  0.330  0.000  1.0
  O  O9  1  0.500  0.544  0.544  1.0
  O  O10  1  0.500  0.000  0.456  1.0
  O  O11  1  0.500  0.456  0.000  1.0
  O  O12  1  0.500  0.803  0.803  1.0
  O  O13  1  0.500  0.000  0.197  1.0
  O  O14  1  0.500  0.197  0.000  1.0
  O  O15  1  0.000  0.757  0.216  1.0
  O  O16  1  0.000  0.460  0.243  1.0
  O  O17  1  0.000  0.540  0.784  1.0
  O  O18  1  0.000  0.784  0.540  1.0
  O  O19  1  0.000  0.216  0.757  1.0
  O  O20  1  0.000  0.243  0.460  1.0
[/CIF]
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