The compound described by Na4Er2(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(2), two equivalent O(1), and four equivalent O(3) atoms. In the second Na site, Na(2) is bonded to six equivalent O(1) 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°. Er(1) is bonded in a 9-coordinate geometry to three equivalent O(2) 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 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(1)Na4Ir2 octahedra, corners with four equivalent O(3)Na2Er2Ir trigonal bipyramids, edges with two equivalent O(1)Na4Ir2 octahedra, edges with four equivalent O(3)Na2Er2Ir trigonal bipyramids, and faces with two equivalent O(1)Na4Ir2 octahedra. The corner-sharing octahedral tilt angles are 45°. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), two equivalent Er(1), and two equivalent Ir(1) atoms. In the third O site, O(3) is bonded to two equivalent Na(1), two equivalent Er(1), and one Ir(1) atom to form distorted ONa2Er2Ir trigonal bipyramids that share corners with two equivalent O(1)Na4Ir2 octahedra, corners with seven equivalent O(3)Na2Er2Ir trigonal bipyramids, edges with two equivalent O(1)Na4Ir2 octahedra, and edges with five equivalent O(3)Na2Er2Ir trigonal bipyramids. The corner-sharing octahedral tilt angles are 51°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4Er2(IrO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.457
_cell_length_b   9.457
_cell_length_c   3.190
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   247.072
_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  0.700  0.000  0.500  1.0
  Na  Na1  1  0.000  0.700  0.500  1.0
  Na  Na2  1  0.300  0.300  0.500  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Er  Er4  1  0.333  0.667  0.500  1.0
  Er  Er5  1  0.667  0.333  0.500  1.0
  Ir  Ir6  1  0.332  0.000  0.000  1.0
  Ir  Ir7  1  0.000  0.332  0.000  1.0
  Ir  Ir8  1  0.668  0.668  0.000  1.0
  O  O9  1  0.198  0.000  0.500  1.0
  O  O10  1  0.000  0.198  0.500  1.0
  O  O11  1  0.802  0.802  0.500  1.0
  O  O12  1  0.460  0.000  0.500  1.0
  O  O13  1  0.000  0.460  0.500  1.0
  O  O14  1  0.540  0.540  0.500  1.0
  O  O15  1  0.244  0.463  0.000  1.0
  O  O16  1  0.537  0.780  0.000  1.0
  O  O17  1  0.463  0.244  0.000  1.0
  O  O18  1  0.220  0.756  0.000  1.0
  O  O19  1  0.780  0.537  0.000  1.0
  O  O20  1  0.756  0.220  0.000  1.0
[/CIF]
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The compound described by Na4Er2(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(2), two equivalent O(1), and four equivalent O(3) atoms. In the second Na site, Na(2) is bonded to six equivalent O(1) 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°. Er(1) is bonded in a 9-coordinate geometry to three equivalent O(2) 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 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(1)Na4Ir2 octahedra, corners with four equivalent O(3)Na2Er2Ir trigonal bipyramids, edges with two equivalent O(1)Na4Ir2 octahedra, edges with four equivalent O(3)Na2Er2Ir trigonal bipyramids, and faces with two equivalent O(1)Na4Ir2 octahedra. The corner-sharing octahedral tilt angles are 45°. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Na(1), two equivalent Er(1), and two equivalent Ir(1) atoms. In the third O site, O(3) is bonded to two equivalent Na(1), two equivalent Er(1), and one Ir(1) atom to form distorted ONa2Er2Ir trigonal bipyramids that share corners with two equivalent O(1)Na4Ir2 octahedra, corners with seven equivalent O(3)Na2Er2Ir trigonal bipyramids, edges with two equivalent O(1)Na4Ir2 octahedra, and edges with five equivalent O(3)Na2Er2Ir trigonal bipyramids. The corner-sharing octahedral tilt angles are 51°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Na4Er2(IrO4)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.457
_cell_length_b   9.457
_cell_length_c   3.190
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   247.072
_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  0.700  0.000  0.500  1.0
  Na  Na1  1  0.000  0.700  0.500  1.0
  Na  Na2  1  0.300  0.300  0.500  1.0
  Na  Na3  1  0.000  0.000  0.000  1.0
  Er  Er4  1  0.333  0.667  0.500  1.0
  Er  Er5  1  0.667  0.333  0.500  1.0
  Ir  Ir6  1  0.332  0.000  0.000  1.0
  Ir  Ir7  1  0.000  0.332  0.000  1.0
  Ir  Ir8  1  0.668  0.668  0.000  1.0
  O  O9  1  0.198  0.000  0.500  1.0
  O  O10  1  0.000  0.198  0.500  1.0
  O  O11  1  0.802  0.802  0.500  1.0
  O  O12  1  0.460  0.000  0.500  1.0
  O  O13  1  0.000  0.460  0.500  1.0
  O  O14  1  0.540  0.540  0.500  1.0
  O  O15  1  0.244  0.463  0.000  1.0
  O  O16  1  0.537  0.780  0.000  1.0
  O  O17  1  0.463  0.244  0.000  1.0
  O  O18  1  0.220  0.756  0.000  1.0
  O  O19  1  0.780  0.537  0.000  1.0
  O  O20  1  0.756  0.220  0.000  1.0
[/CIF]
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