The compound described by Ba2Ni3AlO8 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded in a 12-coordinate geometry to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(3) and four equivalent O(1) atoms to form distorted NiO5 trigonal bipyramids that share  a cornercorner with one Ni(2)O6 octahedra and corners with four equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedra are not tilted. In the second Ni site, Ni(2) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with four equivalent Ni(2)O6 octahedra and corners with two equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedra are not tilted. Al(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Ni(1), and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to four equivalent Ba(1) and two equivalent Ni(2) atoms. In the third O site, O(3) is bonded to four equivalent Ba(1), one Ni(1), and one Ni(2) atom to form a mixture of corner and edge-sharing OBa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. is represented by the CIF card [CIF]
data_Ba2AlNi3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.795
_cell_length_b   3.795
_cell_length_c   11.886
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   171.155
_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
  Ba  Ba0  1  0.500  0.500  0.174  1.0
  Ba  Ba1  1  0.500  0.500  0.826  1.0
  Al  Al2  1  0.500  0.500  0.500  1.0
  Ni  Ni3  1  0.000  0.000  0.357  1.0
  Ni  Ni4  1  0.000  0.000  0.000  1.0
  Ni  Ni5  1  0.000  0.000  0.643  1.0
  O  O6  1  0.000  0.500  0.399  1.0
  O  O7  1  0.500  0.000  0.399  1.0
  O  O8  1  0.500  0.000  0.000  1.0
  O  O9  1  0.000  0.000  0.192  1.0
  O  O10  1  0.000  0.500  0.601  1.0
  O  O11  1  0.500  0.000  0.601  1.0
  O  O12  1  0.000  0.000  0.808  1.0
  O  O13  1  0.000  0.500  0.000  1.0
[/CIF]
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The compound described by Ba2Ni3AlO8 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded in a 12-coordinate geometry to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(3) and four equivalent O(1) atoms to form distorted NiO5 trigonal bipyramids that share  a cornercorner with one Ni(2)O6 octahedra and corners with four equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedra are not tilted. In the second Ni site, Ni(2) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with four equivalent Ni(2)O6 octahedra and corners with two equivalent Ni(1)O5 trigonal bipyramids. The corner-sharing octahedra are not tilted. Al(1) is bonded in a body-centered cubic geometry to eight equivalent O(1) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Ni(1), and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to four equivalent Ba(1) and two equivalent Ni(2) atoms. In the third O site, O(3) is bonded to four equivalent Ba(1), one Ni(1), and one Ni(2) atom to form a mixture of corner and edge-sharing OBa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. is represented by the CIF card [CIF]
data_Ba2AlNi3O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.795
_cell_length_b   3.795
_cell_length_c   11.886
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   171.155
_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
  Ba  Ba0  1  0.500  0.500  0.174  1.0
  Ba  Ba1  1  0.500  0.500  0.826  1.0
  Al  Al2  1  0.500  0.500  0.500  1.0
  Ni  Ni3  1  0.000  0.000  0.357  1.0
  Ni  Ni4  1  0.000  0.000  0.000  1.0
  Ni  Ni5  1  0.000  0.000  0.643  1.0
  O  O6  1  0.000  0.500  0.399  1.0
  O  O7  1  0.500  0.000  0.399  1.0
  O  O8  1  0.500  0.000  0.000  1.0
  O  O9  1  0.000  0.000  0.192  1.0
  O  O10  1  0.000  0.500  0.601  1.0
  O  O11  1  0.500  0.000  0.601  1.0
  O  O12  1  0.000  0.000  0.808  1.0
  O  O13  1  0.000  0.500  0.000  1.0
[/CIF]
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