The compound described by La4Fe(NiO5)2 crystallizes in the tetragonal I4mm space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 9-coordinate geometry to one O(1), four equivalent O(2), and four equivalent O(4) atoms. In the second La site, La(2) is bonded in a 9-coordinate geometry to one O(2), four equivalent O(1), and four equivalent O(3) atoms. In the third La site, La(3) is bonded to four equivalent O(4), four equivalent O(6), and four equivalent O(7) atoms to form LaO12 cuboctahedra that share corners with four equivalent La(3)O12 cuboctahedra, corners with four equivalent La(4)O12 cuboctahedra,  a faceface with one La(4)O12 cuboctahedra, faces with four equivalent La(3)O12 cuboctahedra, faces with four equivalent Ni(1)O6 octahedra, and faces with four equivalent Ni(2)O6 octahedra. In the fourth La site, La(4) is bonded to four equivalent O(3), four equivalent O(5), and four equivalent O(7) atoms to form distorted LaO12 cuboctahedra that share corners with four equivalent La(3)O12 cuboctahedra, corners with four equivalent La(4)O12 cuboctahedra,  a faceface with one La(3)O12 cuboctahedra, faces with four equivalent La(4)O12 cuboctahedra, faces with four equivalent Fe(1)O6 octahedra, and faces with four equivalent Ni(2)O6 octahedra. Fe(1) is bonded to one O(1), one O(5), and four equivalent O(3) atoms to form FeO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, and faces with four equivalent La(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-7°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(6), and four equivalent O(4) atoms to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with four equivalent Ni(1)O6 octahedra, and faces with four equivalent La(3)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Ni site, Ni(2) is bonded to one O(5), one O(6), and four equivalent O(7) atoms to form NiO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Ni(1)O6 octahedra, corners with four equivalent Ni(2)O6 octahedra, faces with four equivalent La(3)O12 cuboctahedra, and faces with four equivalent La(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one La(1), four equivalent La(2), and one Fe(1) atom to form distorted OLa5Fe octahedra that share corners with four equivalent O(4)La4Ni2 octahedra, corners with four equivalent O(1)La5Fe octahedra, and edges with four equivalent O(1)La5Fe octahedra. The corner-sharing octahedral tilt angles range from 19-50°. In the second O site, O(2) is bonded in a 6-coordinate geometry to one La(2), four equivalent La(1), and one Ni(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent La(2), two equivalent La(4), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded to two equivalent La(1), two equivalent La(3), and two equivalent Ni(1) atoms to form distorted OLa4Ni2 octahedra that share corners with two equivalent O(4)La4Ni2 octahedra, corners with two equivalent O(1)La5Fe octahedra, corners with four equivalent O(6)La4Ni2 octahedra, corners with six equivalent O(7)La4Ni2 octahedra,  an edgeedge with one O(7)La4Ni2 octahedra, edges with two equivalent O(4)La4Ni2 octahedra, faces with two equivalent O(6)La4Ni2 octahedra, and faces with four equivalent O(4)La4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. In the fifth O site, O(5) is bonded in a distorted linear geometry to four equivalent La(4), one Fe(1), and one Ni(2) atom. In the sixth O site, O(6) is bonded to four equivalent La(3), one Ni(1), and one Ni(2) atom to form a mixture of distorted face, corner, and edge-sharing OLa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 1-61°. In the seventh O site, O(7) is bonded to two equivalent La(3), two equivalent La(4), and two equivalent Ni(2) atoms to form a mixture of distorted face, corner, and edge-sharing OLa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 1-60°. is represented by the CIF card [CIF]
data_La4Fe(NiO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.436
_cell_length_b   14.436
_cell_length_c   14.436
_cell_angle_alpha   164.454
_cell_angle_beta   164.454
_cell_angle_gamma   22.054
_symmetry_Int_Tables_number   1
_cell_volume   216.053
_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
  La  La0  1  0.303  0.303  0.000  1.0
  La  La1  1  0.701  0.701  0.000  1.0
  La  La2  1  0.431  0.431  0.000  1.0
  La  La3  1  0.561  0.561  0.000  1.0
  Fe  Fe4  1  0.138  0.138  0.000  1.0
  Ni  Ni5  1  0.860  0.860  0.000  1.0
  Ni  Ni6  1  0.999  0.999  0.000  1.0
  O  O7  1  0.217  0.217  0.000  1.0
  O  O8  1  0.782  0.782  0.000  1.0
  O  O9  1  0.142  0.642  0.500  1.0
  O  O10  1  0.360  0.860  0.500  1.0
  O  O11  1  0.860  0.360  0.500  1.0
  O  O12  1  0.642  0.142  0.500  1.0
  O  O13  1  0.070  0.070  0.000  1.0
  O  O14  1  0.931  0.931  0.000  1.0
  O  O15  1  0.001  0.501  0.500  1.0
  O  O16  1  0.501  0.001  0.500  1.0
[/CIF]
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The compound described by La4Fe(NiO5)2 crystallizes in the tetragonal I4mm space group. There are four inequivalent La sites. In the first La site, La(1) is bonded in a 9-coordinate geometry to one O(1), four equivalent O(2), and four equivalent O(4) atoms. In the second La site, La(2) is bonded in a 9-coordinate geometry to one O(2), four equivalent O(1), and four equivalent O(3) atoms. In the third La site, La(3) is bonded to four equivalent O(4), four equivalent O(6), and four equivalent O(7) atoms to form LaO12 cuboctahedra that share corners with four equivalent La(3)O12 cuboctahedra, corners with four equivalent La(4)O12 cuboctahedra,  a faceface with one La(4)O12 cuboctahedra, faces with four equivalent La(3)O12 cuboctahedra, faces with four equivalent Ni(1)O6 octahedra, and faces with four equivalent Ni(2)O6 octahedra. In the fourth La site, La(4) is bonded to four equivalent O(3), four equivalent O(5), and four equivalent O(7) atoms to form distorted LaO12 cuboctahedra that share corners with four equivalent La(3)O12 cuboctahedra, corners with four equivalent La(4)O12 cuboctahedra,  a faceface with one La(3)O12 cuboctahedra, faces with four equivalent La(4)O12 cuboctahedra, faces with four equivalent Fe(1)O6 octahedra, and faces with four equivalent Ni(2)O6 octahedra. Fe(1) is bonded to one O(1), one O(5), and four equivalent O(3) atoms to form FeO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, and faces with four equivalent La(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-7°. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to one O(2), one O(6), and four equivalent O(4) atoms to form NiO6 octahedra that share  a cornercorner with one Ni(2)O6 octahedra, corners with four equivalent Ni(1)O6 octahedra, and faces with four equivalent La(3)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Ni site, Ni(2) is bonded to one O(5), one O(6), and four equivalent O(7) atoms to form NiO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Ni(1)O6 octahedra, corners with four equivalent Ni(2)O6 octahedra, faces with four equivalent La(3)O12 cuboctahedra, and faces with four equivalent La(4)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one La(1), four equivalent La(2), and one Fe(1) atom to form distorted OLa5Fe octahedra that share corners with four equivalent O(4)La4Ni2 octahedra, corners with four equivalent O(1)La5Fe octahedra, and edges with four equivalent O(1)La5Fe octahedra. The corner-sharing octahedral tilt angles range from 19-50°. In the second O site, O(2) is bonded in a 6-coordinate geometry to one La(2), four equivalent La(1), and one Ni(1) atom. In the third O site, O(3) is bonded in a 6-coordinate geometry to two equivalent La(2), two equivalent La(4), and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded to two equivalent La(1), two equivalent La(3), and two equivalent Ni(1) atoms to form distorted OLa4Ni2 octahedra that share corners with two equivalent O(4)La4Ni2 octahedra, corners with two equivalent O(1)La5Fe octahedra, corners with four equivalent O(6)La4Ni2 octahedra, corners with six equivalent O(7)La4Ni2 octahedra,  an edgeedge with one O(7)La4Ni2 octahedra, edges with two equivalent O(4)La4Ni2 octahedra, faces with two equivalent O(6)La4Ni2 octahedra, and faces with four equivalent O(4)La4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 0-61°. In the fifth O site, O(5) is bonded in a distorted linear geometry to four equivalent La(4), one Fe(1), and one Ni(2) atom. In the sixth O site, O(6) is bonded to four equivalent La(3), one Ni(1), and one Ni(2) atom to form a mixture of distorted face, corner, and edge-sharing OLa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 1-61°. In the seventh O site, O(7) is bonded to two equivalent La(3), two equivalent La(4), and two equivalent Ni(2) atoms to form a mixture of distorted face, corner, and edge-sharing OLa4Ni2 octahedra. The corner-sharing octahedral tilt angles range from 1-60°. is represented by the CIF card [CIF]
data_La4Fe(NiO5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   14.436
_cell_length_b   14.436
_cell_length_c   14.436
_cell_angle_alpha   164.454
_cell_angle_beta   164.454
_cell_angle_gamma   22.054
_symmetry_Int_Tables_number   1
_cell_volume   216.053
_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
  La  La0  1  0.303  0.303  0.000  1.0
  La  La1  1  0.701  0.701  0.000  1.0
  La  La2  1  0.431  0.431  0.000  1.0
  La  La3  1  0.561  0.561  0.000  1.0
  Fe  Fe4  1  0.138  0.138  0.000  1.0
  Ni  Ni5  1  0.860  0.860  0.000  1.0
  Ni  Ni6  1  0.999  0.999  0.000  1.0
  O  O7  1  0.217  0.217  0.000  1.0
  O  O8  1  0.782  0.782  0.000  1.0
  O  O9  1  0.142  0.642  0.500  1.0
  O  O10  1  0.360  0.860  0.500  1.0
  O  O11  1  0.860  0.360  0.500  1.0
  O  O12  1  0.642  0.142  0.500  1.0
  O  O13  1  0.070  0.070  0.000  1.0
  O  O14  1  0.931  0.931  0.000  1.0
  O  O15  1  0.001  0.501  0.500  1.0
  O  O16  1  0.501  0.001  0.500  1.0
[/CIF]
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