The structure described by Ba4Ir2AlO10 crystallizes in the orthorhombic Cmc2_1 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(2), one O(5), two equivalent O(3), two equivalent O(4), two equivalent O(6), and two equivalent O(7) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(1), one O(6), two equivalent O(3), two equivalent O(4), two equivalent O(5), and two equivalent O(7) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one O(2), one O(5), two equivalent O(1), two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms. In the fourth Ba site, Ba(4) is bonded in a 10-coordinate geometry to one O(1), one O(6), two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form face-sharing IrO6 octahedra. In the second Ir site, Ir(2) is bonded to one O(2), one O(6), two equivalent O(4), and two equivalent O(7) atoms to form face-sharing IrO6 octahedra. Al(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(7) atoms. There are seven inequivalent O sites. In the first O site, O(3) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ir(1), and one Al(1) atom. In the second O site, O(4) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ir(1), and one Ir(2) atom to form distorted OBa4Ir2 octahedra that share corners with two equivalent O(1)Ba4AlIr octahedra, corners with three equivalent O(2)Ba4Ir2 octahedra,  a faceface with one O(1)Ba4AlIr octahedra,  a faceface with one O(2)Ba4Ir2 octahedra, and faces with two equivalent O(4)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 37-60°. In the third O site, O(5) is bonded in a 1-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), and one Al(1) atom. In the fourth O site, O(6) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(4), two equivalent Ba(1), and one Ir(2) atom. In the fifth O site, O(7) is bonded in a distorted linear geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ir(2), and one Al(1) atom. In the sixth O site, O(1) is bonded to one Ba(2), one Ba(4), two equivalent Ba(3), one Ir(1), and one Al(1) atom to form distorted OBa4AlIr octahedra that share  a cornercorner with one O(2)Ba4Ir2 octahedra, corners with two equivalent O(1)Ba4AlIr octahedra, corners with four equivalent O(4)Ba4Ir2 octahedra, edges with two equivalent O(2)Ba4Ir2 octahedra, and faces with two equivalent O(4)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 2-60°. In the seventh O site, O(2) is bonded to one Ba(1), one Ba(3), two equivalent Ba(4), one Ir(1), and one Ir(2) atom to form OBa4Ir2 octahedra that share  a cornercorner with one O(1)Ba4AlIr octahedra, corners with two equivalent O(2)Ba4Ir2 octahedra, corners with six equivalent O(4)Ba4Ir2 octahedra, edges with two equivalent O(1)Ba4AlIr octahedra, and faces with two equivalent O(4)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 2-56°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba4Al(IrO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.335
_cell_length_b   7.335
_cell_length_c   13.306
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   133.483
_symmetry_Int_Tables_number   1
_cell_volume   519.400
_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  0.487  0.513  0.888  1.0
  Ba  Ba1  1  0.009  0.991  0.116  1.0
  Ba  Ba2  1  0.513  0.487  0.388  1.0
  Ba  Ba3  1  0.991  0.009  0.616  1.0
  Ba  Ba4  1  0.284  0.716  0.639  1.0
  Ba  Ba5  1  0.217  0.783  0.355  1.0
  Ba  Ba6  1  0.716  0.284  0.139  1.0
  Ba  Ba7  1  0.783  0.217  0.855  1.0
  Al  Al8  1  0.609  0.391  0.653  1.0
  Al  Al9  1  0.391  0.609  0.153  1.0
  Ir  Ir10  1  0.750  0.250  0.504  1.0
  Ir  Ir11  1  0.250  0.750  0.004  1.0
  Ir  Ir12  1  0.875  0.125  0.346  1.0
  Ir  Ir13  1  0.125  0.875  0.846  1.0
  O  O14  1  0.783  0.217  0.651  1.0
  O  O15  1  0.720  0.280  0.352  1.0
  O  O16  1  0.217  0.783  0.151  1.0
  O  O17  1  0.280  0.720  0.852  1.0
  O  O18  1  0.422  0.140  0.542  1.0
  O  O19  1  0.631  0.913  0.460  1.0
  O  O20  1  0.140  0.422  0.042  1.0
  O  O21  1  0.913  0.631  0.960  1.0
  O  O22  1  0.087  0.369  0.460  1.0
  O  O23  1  0.860  0.578  0.542  1.0
  O  O24  1  0.369  0.087  0.960  1.0
  O  O25  1  0.578  0.860  0.042  1.0
  O  O26  1  0.476  0.524  0.653  1.0
  O  O27  1  0.020  0.980  0.346  1.0
  O  O28  1  0.524  0.476  0.153  1.0
  O  O29  1  0.980  0.020  0.846  1.0
  O  O30  1  0.382  0.127  0.746  1.0
  O  O31  1  0.618  0.873  0.246  1.0
  O  O32  1  0.127  0.382  0.246  1.0
  O  O33  1  0.873  0.618  0.746  1.0
[/CIF]
.
The structure described by Ba4Ir2AlO10 crystallizes in the orthorhombic Cmc2_1 space group. There are four inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(2), one O(5), two equivalent O(3), two equivalent O(4), two equivalent O(6), and two equivalent O(7) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(1), one O(6), two equivalent O(3), two equivalent O(4), two equivalent O(5), and two equivalent O(7) atoms. In the third Ba site, Ba(3) is bonded in a 10-coordinate geometry to one O(2), one O(5), two equivalent O(1), two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms. In the fourth Ba site, Ba(4) is bonded in a 10-coordinate geometry to one O(1), one O(6), two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(7) atoms. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to one O(1), one O(2), two equivalent O(3), and two equivalent O(4) atoms to form face-sharing IrO6 octahedra. In the second Ir site, Ir(2) is bonded to one O(2), one O(6), two equivalent O(4), and two equivalent O(7) atoms to form face-sharing IrO6 octahedra. Al(1) is bonded in a 6-coordinate geometry to one O(1), one O(5), two equivalent O(3), and two equivalent O(7) atoms. There are seven inequivalent O sites. In the first O site, O(3) is bonded in a 6-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ir(1), and one Al(1) atom. In the second O site, O(4) is bonded to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ir(1), and one Ir(2) atom to form distorted OBa4Ir2 octahedra that share corners with two equivalent O(1)Ba4AlIr octahedra, corners with three equivalent O(2)Ba4Ir2 octahedra,  a faceface with one O(1)Ba4AlIr octahedra,  a faceface with one O(2)Ba4Ir2 octahedra, and faces with two equivalent O(4)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 37-60°. In the third O site, O(5) is bonded in a 1-coordinate geometry to one Ba(1), one Ba(3), two equivalent Ba(2), and one Al(1) atom. In the fourth O site, O(6) is bonded in a 5-coordinate geometry to one Ba(2), one Ba(4), two equivalent Ba(1), and one Ir(2) atom. In the fifth O site, O(7) is bonded in a distorted linear geometry to one Ba(1), one Ba(2), one Ba(3), one Ba(4), one Ir(2), and one Al(1) atom. In the sixth O site, O(1) is bonded to one Ba(2), one Ba(4), two equivalent Ba(3), one Ir(1), and one Al(1) atom to form distorted OBa4AlIr octahedra that share  a cornercorner with one O(2)Ba4Ir2 octahedra, corners with two equivalent O(1)Ba4AlIr octahedra, corners with four equivalent O(4)Ba4Ir2 octahedra, edges with two equivalent O(2)Ba4Ir2 octahedra, and faces with two equivalent O(4)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 2-60°. In the seventh O site, O(2) is bonded to one Ba(1), one Ba(3), two equivalent Ba(4), one Ir(1), and one Ir(2) atom to form OBa4Ir2 octahedra that share  a cornercorner with one O(1)Ba4AlIr octahedra, corners with two equivalent O(2)Ba4Ir2 octahedra, corners with six equivalent O(4)Ba4Ir2 octahedra, edges with two equivalent O(1)Ba4AlIr octahedra, and faces with two equivalent O(4)Ba4Ir2 octahedra. The corner-sharing octahedral tilt angles range from 2-56°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba4Al(IrO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.335
_cell_length_b   7.335
_cell_length_c   13.306
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   133.483
_symmetry_Int_Tables_number   1
_cell_volume   519.400
_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  0.487  0.513  0.888  1.0
  Ba  Ba1  1  0.009  0.991  0.116  1.0
  Ba  Ba2  1  0.513  0.487  0.388  1.0
  Ba  Ba3  1  0.991  0.009  0.616  1.0
  Ba  Ba4  1  0.284  0.716  0.639  1.0
  Ba  Ba5  1  0.217  0.783  0.355  1.0
  Ba  Ba6  1  0.716  0.284  0.139  1.0
  Ba  Ba7  1  0.783  0.217  0.855  1.0
  Al  Al8  1  0.609  0.391  0.653  1.0
  Al  Al9  1  0.391  0.609  0.153  1.0
  Ir  Ir10  1  0.750  0.250  0.504  1.0
  Ir  Ir11  1  0.250  0.750  0.004  1.0
  Ir  Ir12  1  0.875  0.125  0.346  1.0
  Ir  Ir13  1  0.125  0.875  0.846  1.0
  O  O14  1  0.783  0.217  0.651  1.0
  O  O15  1  0.720  0.280  0.352  1.0
  O  O16  1  0.217  0.783  0.151  1.0
  O  O17  1  0.280  0.720  0.852  1.0
  O  O18  1  0.422  0.140  0.542  1.0
  O  O19  1  0.631  0.913  0.460  1.0
  O  O20  1  0.140  0.422  0.042  1.0
  O  O21  1  0.913  0.631  0.960  1.0
  O  O22  1  0.087  0.369  0.460  1.0
  O  O23  1  0.860  0.578  0.542  1.0
  O  O24  1  0.369  0.087  0.960  1.0
  O  O25  1  0.578  0.860  0.042  1.0
  O  O26  1  0.476  0.524  0.653  1.0
  O  O27  1  0.020  0.980  0.346  1.0
  O  O28  1  0.524  0.476  0.153  1.0
  O  O29  1  0.980  0.020  0.846  1.0
  O  O30  1  0.382  0.127  0.746  1.0
  O  O31  1  0.618  0.873  0.246  1.0
  O  O32  1  0.127  0.382  0.246  1.0
  O  O33  1  0.873  0.618  0.746  1.0
[/CIF]
.