The material described by BaNiCuAlO5 crystallizes in the tetragonal P4mm space group. Ba(1) is bonded in a distorted square co-planar geometry to four equivalent O(3) atoms. 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 Cu(1)O5 trigonal bipyramid and corners with four equivalent Ni(1)O5 trigonal bipyramids. Cu(1) is bonded to one O(3) and four equivalent O(2) atoms to form distorted CuO5 trigonal bipyramids that share  a cornercorner with one Ni(1)O5 trigonal bipyramid and corners with four equivalent Cu(1)O5 trigonal bipyramids. Al(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ni(1) and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Cu(1) and two equivalent Al(1) atoms. In the third O site, O(3) is bonded to four equivalent Ba(1), one Ni(1), and one Cu(1) atom to form a mixture of edge and corner-sharing OBa4CuNi octahedra. The corner-sharing octahedral tilt angles are 8°. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaAlCuNiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.716
_cell_length_b   3.716
_cell_length_c   7.620
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   105.233
_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  0.000  0.000  0.976  1.0
  Al  Al1  1  0.000  0.000  0.480  1.0
  Cu  Cu2  1  0.500  0.500  0.246  1.0
  Ni  Ni3  1  0.500  0.500  0.688  1.0
  O  O4  1  0.000  0.500  0.620  1.0
  O  O5  1  0.500  0.000  0.620  1.0
  O  O6  1  0.000  0.500  0.303  1.0
  O  O7  1  0.500  0.000  0.303  1.0
  O  O8  1  0.500  0.500  0.951  1.0
[/CIF]
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The material described by BaNiCuAlO5 crystallizes in the tetragonal P4mm space group. Ba(1) is bonded in a distorted square co-planar geometry to four equivalent O(3) atoms. 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 Cu(1)O5 trigonal bipyramid and corners with four equivalent Ni(1)O5 trigonal bipyramids. Cu(1) is bonded to one O(3) and four equivalent O(2) atoms to form distorted CuO5 trigonal bipyramids that share  a cornercorner with one Ni(1)O5 trigonal bipyramid and corners with four equivalent Cu(1)O5 trigonal bipyramids. Al(1) is bonded in a body-centered cubic geometry to four equivalent O(1) and four equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ni(1) and two equivalent Al(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Cu(1) and two equivalent Al(1) atoms. In the third O site, O(3) is bonded to four equivalent Ba(1), one Ni(1), and one Cu(1) atom to form a mixture of edge and corner-sharing OBa4CuNi octahedra. The corner-sharing octahedral tilt angles are 8°. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaAlCuNiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.716
_cell_length_b   3.716
_cell_length_c   7.620
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   105.233
_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  0.000  0.000  0.976  1.0
  Al  Al1  1  0.000  0.000  0.480  1.0
  Cu  Cu2  1  0.500  0.500  0.246  1.0
  Ni  Ni3  1  0.500  0.500  0.688  1.0
  O  O4  1  0.000  0.500  0.620  1.0
  O  O5  1  0.500  0.000  0.620  1.0
  O  O6  1  0.000  0.500  0.303  1.0
  O  O7  1  0.500  0.000  0.303  1.0
  O  O8  1  0.500  0.500  0.951  1.0
[/CIF]
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