The material structure described by Pr2NiO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. Pr(1) is bonded in a 9-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. Ni(1) is bonded to two equivalent O(1) and four equivalent O(2) 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(2) is bonded to four equivalent Pr(1) and two equivalent Ni(1) atoms to form OPr4Ni2 octahedra that share corners with two equivalent O(2)Pr4Ni2 octahedra, corners with twelve equivalent O(1)Pr5Ni octahedra, edges with two equivalent O(2)Pr4Ni2 octahedra, faces with four equivalent O(2)Pr4Ni2 octahedra, and faces with four equivalent O(1)Pr5Ni octahedra. The corner-sharing octahedral tilt angles range from 0-50°. In the second O site, O(1) is bonded to five equivalent Pr(1) and one Ni(1) atom to form distorted OPr5Ni octahedra that share corners with five equivalent O(1)Pr5Ni octahedra, corners with twelve equivalent O(2)Pr4Ni2 octahedra, edges with eight equivalent O(1)Pr5Ni octahedra, and faces with four equivalent O(2)Pr4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-50°. is represented by the CIF card [CIF]
data_Pr2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.882
_cell_length_b   3.882
_cell_length_c   6.801
_cell_angle_alpha   106.567
_cell_angle_beta   106.567
_cell_angle_gamma   90.051
_symmetry_Int_Tables_number   1
_cell_volume   93.753
_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
  Pr  Pr0  1  0.636  0.636  0.271  1.0
  Pr  Pr1  1  0.364  0.364  0.729  1.0
  Ni  Ni2  1  0.000  0.000  0.000  1.0
  O  O3  1  0.822  0.822  0.644  1.0
  O  O4  1  0.178  0.178  0.356  1.0
  O  O5  1  0.000  0.500  0.000  1.0
  O  O6  1  0.500  0.000  0.000  1.0
[/CIF]
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The material structure described by Pr2NiO4 is (La,Ba)CuO4 structured and crystallizes in the tetragonal I4/mmm space group. Pr(1) is bonded in a 9-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. Ni(1) is bonded to two equivalent O(1) and four equivalent O(2) 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(2) is bonded to four equivalent Pr(1) and two equivalent Ni(1) atoms to form OPr4Ni2 octahedra that share corners with two equivalent O(2)Pr4Ni2 octahedra, corners with twelve equivalent O(1)Pr5Ni octahedra, edges with two equivalent O(2)Pr4Ni2 octahedra, faces with four equivalent O(2)Pr4Ni2 octahedra, and faces with four equivalent O(1)Pr5Ni octahedra. The corner-sharing octahedral tilt angles range from 0-50°. In the second O site, O(1) is bonded to five equivalent Pr(1) and one Ni(1) atom to form distorted OPr5Ni octahedra that share corners with five equivalent O(1)Pr5Ni octahedra, corners with twelve equivalent O(2)Pr4Ni2 octahedra, edges with eight equivalent O(1)Pr5Ni octahedra, and faces with four equivalent O(2)Pr4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-50°. is represented by the CIF card [CIF]
data_Pr2NiO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.882
_cell_length_b   3.882
_cell_length_c   6.801
_cell_angle_alpha   106.567
_cell_angle_beta   106.567
_cell_angle_gamma   90.051
_symmetry_Int_Tables_number   1
_cell_volume   93.753
_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
  Pr  Pr0  1  0.636  0.636  0.271  1.0
  Pr  Pr1  1  0.364  0.364  0.729  1.0
  Ni  Ni2  1  0.000  0.000  0.000  1.0
  O  O3  1  0.822  0.822  0.644  1.0
  O  O4  1  0.178  0.178  0.356  1.0
  O  O5  1  0.000  0.500  0.000  1.0
  O  O6  1  0.500  0.000  0.000  1.0
[/CIF]
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