The crystal structure described by Ba3NdIr2O9 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(5) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Nd(1)O6 octahedra, and faces with six equivalent Ir(1)O6 octahedra. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to one O(3), two equivalent O(5), three equivalent O(1), three equivalent O(2), and three equivalent O(4) atoms. Nd(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form NdO6 octahedra that share corners with six equivalent Ir(1)O6 octahedra and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 7-11°. Ir(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form IrO6 octahedra that share corners with three equivalent Nd(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, and  a faceface with one Ir(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-11°. There are five inequivalent O sites. In the first O site, O(3) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ir(1) atoms to form a mixture of distorted face and corner-sharing OBa4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 5-60°. In the second O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Nd(1), and one Ir(1) atom. In the third O site, O(5) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ir(1) atoms to form a mixture of distorted face and corner-sharing OBa4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 6-60°. In the fourth O site, O(1) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Nd(1), and one Ir(1) atom. In the fifth O site, O(2) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Nd(1), and one Ir(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3NdIr2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.991
_cell_length_b   5.991
_cell_length_c   15.052
_cell_angle_alpha   89.197
_cell_angle_beta   89.197
_cell_angle_gamma   119.852
_symmetry_Int_Tables_number   1
_cell_volume   468.325
_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
  Ba  Ba0  1  0.997  0.003  0.750  1.0
  Ba  Ba1  1  0.003  0.997  0.250  1.0
  Ba  Ba2  1  0.328  0.659  0.600  1.0
  Ba  Ba3  1  0.672  0.341  0.401  1.0
  Ba  Ba4  1  0.341  0.672  0.900  1.0
  Ba  Ba5  1  0.659  0.328  0.100  1.0
  Nd  Nd6  1  0.000  0.000  0.500  1.0
  Nd  Nd7  1  0.000  0.000  0.000  1.0
  Ir  Ir8  1  0.653  0.319  0.666  1.0
  Ir  Ir9  1  0.347  0.681  0.334  1.0
  Ir  Ir10  1  0.681  0.347  0.834  1.0
  Ir  Ir11  1  0.319  0.653  0.166  1.0
  O  O12  1  0.796  0.148  0.593  1.0
  O  O13  1  0.204  0.852  0.407  1.0
  O  O14  1  0.852  0.204  0.907  1.0
  O  O15  1  0.148  0.796  0.093  1.0
  O  O16  1  0.329  0.148  0.600  1.0
  O  O17  1  0.671  0.852  0.400  1.0
  O  O18  1  0.852  0.671  0.900  1.0
  O  O19  1  0.148  0.329  0.100  1.0
  O  O20  1  0.508  0.492  0.750  1.0
  O  O21  1  0.492  0.508  0.250  1.0
  O  O22  1  0.390  0.206  0.921  1.0
  O  O23  1  0.610  0.794  0.079  1.0
  O  O24  1  0.794  0.610  0.579  1.0
  O  O25  1  0.206  0.390  0.421  1.0
  O  O26  1  0.508  0.021  0.759  1.0
  O  O27  1  0.492  0.979  0.241  1.0
  O  O28  1  0.979  0.492  0.741  1.0
  O  O29  1  0.021  0.508  0.259  1.0
[/CIF]
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The crystal structure described by Ba3NdIr2O9 crystallizes in the monoclinic C2/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to two equivalent O(1), two equivalent O(2), two equivalent O(3), two equivalent O(4), and four equivalent O(5) atoms to form distorted BaO12 cuboctahedra that share corners with six equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Nd(1)O6 octahedra, and faces with six equivalent Ir(1)O6 octahedra. In the second Ba site, Ba(2) is bonded in a 12-coordinate geometry to one O(3), two equivalent O(5), three equivalent O(1), three equivalent O(2), and three equivalent O(4) atoms. Nd(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form NdO6 octahedra that share corners with six equivalent Ir(1)O6 octahedra and faces with two equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 7-11°. Ir(1) is bonded to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms to form IrO6 octahedra that share corners with three equivalent Nd(1)O6 octahedra, faces with three equivalent Ba(1)O12 cuboctahedra, and  a faceface with one Ir(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-11°. There are five inequivalent O sites. In the first O site, O(3) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ir(1) atoms to form a mixture of distorted face and corner-sharing OBa4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 5-60°. In the second O site, O(4) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Nd(1), and one Ir(1) atom. In the third O site, O(5) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Ir(1) atoms to form a mixture of distorted face and corner-sharing OBa4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 6-60°. In the fourth O site, O(1) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Nd(1), and one Ir(1) atom. In the fifth O site, O(2) is bonded in a 2-coordinate geometry to one Ba(1), three equivalent Ba(2), one Nd(1), and one Ir(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba3NdIr2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.991
_cell_length_b   5.991
_cell_length_c   15.052
_cell_angle_alpha   89.197
_cell_angle_beta   89.197
_cell_angle_gamma   119.852
_symmetry_Int_Tables_number   1
_cell_volume   468.325
_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
  Ba  Ba0  1  0.997  0.003  0.750  1.0
  Ba  Ba1  1  0.003  0.997  0.250  1.0
  Ba  Ba2  1  0.328  0.659  0.600  1.0
  Ba  Ba3  1  0.672  0.341  0.401  1.0
  Ba  Ba4  1  0.341  0.672  0.900  1.0
  Ba  Ba5  1  0.659  0.328  0.100  1.0
  Nd  Nd6  1  0.000  0.000  0.500  1.0
  Nd  Nd7  1  0.000  0.000  0.000  1.0
  Ir  Ir8  1  0.653  0.319  0.666  1.0
  Ir  Ir9  1  0.347  0.681  0.334  1.0
  Ir  Ir10  1  0.681  0.347  0.834  1.0
  Ir  Ir11  1  0.319  0.653  0.166  1.0
  O  O12  1  0.796  0.148  0.593  1.0
  O  O13  1  0.204  0.852  0.407  1.0
  O  O14  1  0.852  0.204  0.907  1.0
  O  O15  1  0.148  0.796  0.093  1.0
  O  O16  1  0.329  0.148  0.600  1.0
  O  O17  1  0.671  0.852  0.400  1.0
  O  O18  1  0.852  0.671  0.900  1.0
  O  O19  1  0.148  0.329  0.100  1.0
  O  O20  1  0.508  0.492  0.750  1.0
  O  O21  1  0.492  0.508  0.250  1.0
  O  O22  1  0.390  0.206  0.921  1.0
  O  O23  1  0.610  0.794  0.079  1.0
  O  O24  1  0.794  0.610  0.579  1.0
  O  O25  1  0.206  0.390  0.421  1.0
  O  O26  1  0.508  0.021  0.759  1.0
  O  O27  1  0.492  0.979  0.241  1.0
  O  O28  1  0.979  0.492  0.741  1.0
  O  O29  1  0.021  0.508  0.259  1.0
[/CIF]
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