The material described by Y2BaNiO5 crystallizes in the orthorhombic Immm space group. Ba(1) is bonded in a distorted q6 geometry to two equivalent O(2) and eight equivalent O(1) atoms. Y(1) is bonded in a 7-coordinate geometry to one O(2) and six equivalent O(1) atoms. Ni(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), three equivalent Y(1), and one Ni(1) atom to form distorted OBa2Y3Ni octahedra that share corners with three equivalent O(2)Ba2Y2Ni2 octahedra, corners with thirteen equivalent O(1)Ba2Y3Ni octahedra, edges with five equivalent O(1)Ba2Y3Ni octahedra, faces with two equivalent O(2)Ba2Y2Ni2 octahedra, and faces with three equivalent O(1)Ba2Y3Ni octahedra. The corner-sharing octahedral tilt angles range from 0-70°. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Y(1), and two equivalent Ni(1) atoms to form distorted OBa2Y2Ni2 octahedra that share corners with four equivalent O(2)Ba2Y2Ni2 octahedra, corners with twelve equivalent O(1)Ba2Y3Ni octahedra, and faces with eight equivalent O(1)Ba2Y3Ni octahedra. The corner-sharing octahedral tilt angles range from 0-59°. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaY2NiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.803
_cell_length_b   5.818
_cell_length_c   6.701
_cell_angle_alpha   115.730
_cell_angle_beta   106.486
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   126.753
_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  0.000  1.0
  Y  Y1  1  0.797  0.297  0.593  1.0
  Y  Y2  1  0.203  0.703  0.407  1.0
  Ni  Ni3  1  0.500  0.500  0.000  1.0
  O  O4  1  0.351  0.110  0.701  1.0
  O  O5  1  0.649  0.890  0.299  1.0
  O  O6  1  0.649  0.409  0.299  1.0
  O  O7  1  0.351  0.591  0.701  1.0
  O  O8  1  0.000  0.500  1.000  1.0
[/CIF]
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The material described by Y2BaNiO5 crystallizes in the orthorhombic Immm space group. Ba(1) is bonded in a distorted q6 geometry to two equivalent O(2) and eight equivalent O(1) atoms. Y(1) is bonded in a 7-coordinate geometry to one O(2) and six equivalent O(1) atoms. Ni(1) is bonded to two equivalent O(2) and four equivalent O(1) atoms to form corner-sharing NiO6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ba(1), three equivalent Y(1), and one Ni(1) atom to form distorted OBa2Y3Ni octahedra that share corners with three equivalent O(2)Ba2Y2Ni2 octahedra, corners with thirteen equivalent O(1)Ba2Y3Ni octahedra, edges with five equivalent O(1)Ba2Y3Ni octahedra, faces with two equivalent O(2)Ba2Y2Ni2 octahedra, and faces with three equivalent O(1)Ba2Y3Ni octahedra. The corner-sharing octahedral tilt angles range from 0-70°. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Y(1), and two equivalent Ni(1) atoms to form distorted OBa2Y2Ni2 octahedra that share corners with four equivalent O(2)Ba2Y2Ni2 octahedra, corners with twelve equivalent O(1)Ba2Y3Ni octahedra, and faces with eight equivalent O(1)Ba2Y3Ni octahedra. The corner-sharing octahedral tilt angles range from 0-59°. is represented by the Crystallographic Information File (CIF) [CIF]
data_BaY2NiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.803
_cell_length_b   5.818
_cell_length_c   6.701
_cell_angle_alpha   115.730
_cell_angle_beta   106.486
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   126.753
_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  0.000  1.0
  Y  Y1  1  0.797  0.297  0.593  1.0
  Y  Y2  1  0.203  0.703  0.407  1.0
  Ni  Ni3  1  0.500  0.500  0.000  1.0
  O  O4  1  0.351  0.110  0.701  1.0
  O  O5  1  0.649  0.890  0.299  1.0
  O  O6  1  0.649  0.409  0.299  1.0
  O  O7  1  0.351  0.591  0.701  1.0
  O  O8  1  0.000  0.500  1.000  1.0
[/CIF]
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