The material described by La2Ni2O5 crystallizes in the orthorhombic Ima2 space group. La(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent O(3), and four equivalent O(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with four equivalent Ni(1)O6 octahedra and corners with two equivalent Ni(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 13°. In the second Ni site, Ni(2) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form NiO4 tetrahedra that share corners with two equivalent Ni(1)O6 octahedra and corners with two equivalent Ni(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 35°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent La(1) and two equivalent Ni(2) atoms to form distorted OLa2Ni2 tetrahedra that share corners with eight equivalent O(2)La4Ni2 octahedra and corners with two equivalent O(1)La2Ni2 tetrahedra. The corner-sharing octahedral tilt angles range from 24-75°. In the second O site, O(2) is bonded to four equivalent La(1) and two equivalent Ni(1) atoms to form distorted OLa4Ni2 octahedra that share corners with two equivalent O(2)La4Ni2 octahedra, corners with four equivalent O(1)La2Ni2 tetrahedra, edges with two equivalent O(2)La4Ni2 octahedra, and faces with four equivalent O(2)La4Ni2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the third O site, O(3) is bonded in a 5-coordinate geometry to three equivalent La(1), one Ni(1), and one Ni(2) atom. is represented by the CIF card [CIF]
data_La2Ni2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.464
_cell_length_b   5.691
_cell_length_c   8.854
_cell_angle_alpha   108.753
_cell_angle_beta   72.030
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   246.450
_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
  La  La0  1  0.397  0.125  0.218  1.0
  La  La1  1  0.615  0.875  0.782  1.0
  La  La2  1  0.897  0.593  0.218  1.0
  La  La3  1  0.115  0.407  0.782  1.0
  Ni  Ni4  1  0.511  0.500  0.000  1.0
  Ni  Ni5  1  0.218  0.809  0.500  1.0
  Ni  Ni6  1  0.011  0.000  0.000  1.0
  Ni  Ni7  1  0.718  0.191  0.500  1.0
  O  O8  1  0.348  0.140  0.500  1.0
  O  O9  1  0.848  0.860  0.500  1.0
  O  O10  1  0.270  0.241  0.972  1.0
  O  O11  1  0.242  0.759  0.028  1.0
  O  O12  1  0.770  0.231  0.972  1.0
  O  O13  1  0.742  0.769  0.028  1.0
  O  O14  1  0.894  0.206  0.275  1.0
  O  O15  1  0.168  0.794  0.725  1.0
  O  O16  1  0.394  0.569  0.275  1.0
  O  O17  1  0.668  0.432  0.725  1.0
[/CIF]
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The material described by La2Ni2O5 crystallizes in the orthorhombic Ima2 space group. La(1) is bonded in a 8-coordinate geometry to one O(1), three equivalent O(3), and four equivalent O(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form NiO6 octahedra that share corners with four equivalent Ni(1)O6 octahedra and corners with two equivalent Ni(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 13°. In the second Ni site, Ni(2) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form NiO4 tetrahedra that share corners with two equivalent Ni(1)O6 octahedra and corners with two equivalent Ni(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 35°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent La(1) and two equivalent Ni(2) atoms to form distorted OLa2Ni2 tetrahedra that share corners with eight equivalent O(2)La4Ni2 octahedra and corners with two equivalent O(1)La2Ni2 tetrahedra. The corner-sharing octahedral tilt angles range from 24-75°. In the second O site, O(2) is bonded to four equivalent La(1) and two equivalent Ni(1) atoms to form distorted OLa4Ni2 octahedra that share corners with two equivalent O(2)La4Ni2 octahedra, corners with four equivalent O(1)La2Ni2 tetrahedra, edges with two equivalent O(2)La4Ni2 octahedra, and faces with four equivalent O(2)La4Ni2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the third O site, O(3) is bonded in a 5-coordinate geometry to three equivalent La(1), one Ni(1), and one Ni(2) atom. is represented by the CIF card [CIF]
data_La2Ni2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.464
_cell_length_b   5.691
_cell_length_c   8.854
_cell_angle_alpha   108.753
_cell_angle_beta   72.030
_cell_angle_gamma   89.999
_symmetry_Int_Tables_number   1
_cell_volume   246.450
_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
  La  La0  1  0.397  0.125  0.218  1.0
  La  La1  1  0.615  0.875  0.782  1.0
  La  La2  1  0.897  0.593  0.218  1.0
  La  La3  1  0.115  0.407  0.782  1.0
  Ni  Ni4  1  0.511  0.500  0.000  1.0
  Ni  Ni5  1  0.218  0.809  0.500  1.0
  Ni  Ni6  1  0.011  0.000  0.000  1.0
  Ni  Ni7  1  0.718  0.191  0.500  1.0
  O  O8  1  0.348  0.140  0.500  1.0
  O  O9  1  0.848  0.860  0.500  1.0
  O  O10  1  0.270  0.241  0.972  1.0
  O  O11  1  0.242  0.759  0.028  1.0
  O  O12  1  0.770  0.231  0.972  1.0
  O  O13  1  0.742  0.769  0.028  1.0
  O  O14  1  0.894  0.206  0.275  1.0
  O  O15  1  0.168  0.794  0.725  1.0
  O  O16  1  0.394  0.569  0.275  1.0
  O  O17  1  0.668  0.432  0.725  1.0
[/CIF]
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