The compound described by Ba4Pr4Fe4Cu4O21 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded to two equivalent O(3), two equivalent O(4), four equivalent O(1), and four equivalent O(2) atoms to form distorted BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Fe(1)O6 octahedra, faces with two equivalent Cu(1)O5 square pyramids, faces with two equivalent Cu(2)O5 square pyramids, and faces with two equivalent Fe(2)O5 trigonal bipyramids. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 10-coordinate geometry to two equivalent O(5) and eight equivalent O(1) atoms. In the second Pr site, Pr(2) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(5), and four equivalent O(1) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Cu(1)O5 square pyramid, corners with four equivalent Fe(2)O5 trigonal bipyramids, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Fe site, Fe(2) is bonded to one O(4) and four equivalent O(1) atoms to form distorted FeO5 trigonal bipyramids that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Cu(2)O5 square pyramid, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 21°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(3) and four equivalent O(2) atoms to form CuO5 square pyramids that share  a cornercorner with one Fe(1)O6 octahedra, corners with four equivalent Cu(2)O5 square pyramids, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Cu site, Cu(2) is bonded to one O(4) and four equivalent O(2) atoms to form CuO5 square pyramids that share corners with four equivalent Cu(1)O5 square pyramids,  a cornercorner with one Fe(2)O5 trigonal bipyramid, and faces with four equivalent Ba(1)O12 cuboctahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Pr(1), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Pr(2), one Cu(1), and one Cu(2) atom. In the third O site, O(3) is bonded to four equivalent Ba(1), one Fe(1), and one Cu(1) atom to form a mixture of distorted edge and corner-sharing OBa4FeCu octahedra. The corner-sharing octahedral tilt angles are 14°. In the fourth O site, O(4) is bonded to four equivalent Ba(1), one Fe(2), and one Cu(2) atom to form a mixture of distorted edge and corner-sharing OBa4FeCu octahedra. The corner-sharing octahedral tilt angles are 7°. In the fifth O site, O(5) is bonded in a linear geometry to four equivalent Pr(1) and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba4Pr4Fe4Cu4O21
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.329
_cell_length_b   16.329
_cell_length_c   16.329
_cell_angle_alpha   160.227
_cell_angle_beta   160.227
_cell_angle_gamma   28.106
_symmetry_Int_Tables_number   1
_cell_volume   498.042
_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  0.870  0.370  0.500  1.0
  Ba  Ba1  1  0.130  0.630  0.500  1.0
  Ba  Ba2  1  0.370  0.870  0.500  1.0
  Ba  Ba3  1  0.630  0.130  0.500  1.0
  Pr  Pr4  1  0.000  0.500  0.500  1.0
  Pr  Pr5  1  0.250  0.750  0.500  1.0
  Pr  Pr6  1  0.500  0.000  0.500  1.0
  Pr  Pr7  1  0.750  0.250  0.500  1.0
  Fe  Fe8  1  0.560  0.560  0.000  1.0
  Fe  Fe9  1  0.066  0.066  0.000  1.0
  Fe  Fe10  1  0.440  0.440  0.000  1.0
  Fe  Fe11  1  0.934  0.934  0.000  1.0
  Cu  Cu12  1  0.306  0.306  0.000  1.0
  Cu  Cu13  1  0.806  0.806  0.000  1.0
  Cu  Cu14  1  0.194  0.194  0.000  1.0
  Cu  Cu15  1  0.694  0.694  0.000  1.0
  O  O16  1  0.292  0.292  0.481  1.0
  O  O17  1  0.547  0.547  0.497  1.0
  O  O18  1  0.811  0.811  0.519  1.0
  O  O19  1  0.051  0.051  0.503  1.0
  O  O20  1  0.292  0.811  0.000  1.0
  O  O21  1  0.547  0.051  0.000  1.0
  O  O22  1  0.811  0.292  0.000  1.0
  O  O23  1  0.051  0.547  0.000  1.0
  O  O24  1  0.189  0.189  0.481  1.0
  O  O25  1  0.453  0.453  0.503  1.0
  O  O26  1  0.708  0.708  0.519  1.0
  O  O27  1  0.949  0.949  0.497  1.0
  O  O28  1  0.189  0.708  0.000  1.0
  O  O29  1  0.453  0.949  0.000  1.0
  O  O30  1  0.708  0.189  0.000  1.0
  O  O31  1  0.949  0.453  0.000  1.0
  O  O32  1  0.381  0.381  0.000  1.0
  O  O33  1  0.619  0.619  0.000  1.0
  O  O34  1  0.875  0.875  0.000  1.0
  O  O35  1  0.125  0.125  0.000  1.0
  O  O36  1  0.500  0.500  0.000  1.0
[/CIF]
.
The compound described by Ba4Pr4Fe4Cu4O21 crystallizes in the tetragonal I4/mmm space group. Ba(1) is bonded to two equivalent O(3), two equivalent O(4), four equivalent O(1), and four equivalent O(2) atoms to form distorted BaO12 cuboctahedra that share corners with four equivalent Ba(1)O12 cuboctahedra, faces with four equivalent Ba(1)O12 cuboctahedra, faces with two equivalent Fe(1)O6 octahedra, faces with two equivalent Cu(1)O5 square pyramids, faces with two equivalent Cu(2)O5 square pyramids, and faces with two equivalent Fe(2)O5 trigonal bipyramids. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 10-coordinate geometry to two equivalent O(5) and eight equivalent O(1) atoms. In the second Pr site, Pr(2) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(5), and four equivalent O(1) atoms to form FeO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Cu(1)O5 square pyramid, corners with four equivalent Fe(2)O5 trigonal bipyramids, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Fe site, Fe(2) is bonded to one O(4) and four equivalent O(1) atoms to form distorted FeO5 trigonal bipyramids that share corners with four equivalent Fe(1)O6 octahedra,  a cornercorner with one Cu(2)O5 square pyramid, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles are 21°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one O(3) and four equivalent O(2) atoms to form CuO5 square pyramids that share  a cornercorner with one Fe(1)O6 octahedra, corners with four equivalent Cu(2)O5 square pyramids, and faces with four equivalent Ba(1)O12 cuboctahedra. The corner-sharing octahedra are not tilted. In the second Cu site, Cu(2) is bonded to one O(4) and four equivalent O(2) atoms to form CuO5 square pyramids that share corners with four equivalent Cu(1)O5 square pyramids,  a cornercorner with one Fe(2)O5 trigonal bipyramid, and faces with four equivalent Ba(1)O12 cuboctahedra. There are five inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Pr(1), one Fe(1), and one Fe(2) atom. In the second O site, O(2) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Pr(2), one Cu(1), and one Cu(2) atom. In the third O site, O(3) is bonded to four equivalent Ba(1), one Fe(1), and one Cu(1) atom to form a mixture of distorted edge and corner-sharing OBa4FeCu octahedra. The corner-sharing octahedral tilt angles are 14°. In the fourth O site, O(4) is bonded to four equivalent Ba(1), one Fe(2), and one Cu(2) atom to form a mixture of distorted edge and corner-sharing OBa4FeCu octahedra. The corner-sharing octahedral tilt angles are 7°. In the fifth O site, O(5) is bonded in a linear geometry to four equivalent Pr(1) and two equivalent Fe(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba4Pr4Fe4Cu4O21
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.329
_cell_length_b   16.329
_cell_length_c   16.329
_cell_angle_alpha   160.227
_cell_angle_beta   160.227
_cell_angle_gamma   28.106
_symmetry_Int_Tables_number   1
_cell_volume   498.042
_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  0.870  0.370  0.500  1.0
  Ba  Ba1  1  0.130  0.630  0.500  1.0
  Ba  Ba2  1  0.370  0.870  0.500  1.0
  Ba  Ba3  1  0.630  0.130  0.500  1.0
  Pr  Pr4  1  0.000  0.500  0.500  1.0
  Pr  Pr5  1  0.250  0.750  0.500  1.0
  Pr  Pr6  1  0.500  0.000  0.500  1.0
  Pr  Pr7  1  0.750  0.250  0.500  1.0
  Fe  Fe8  1  0.560  0.560  0.000  1.0
  Fe  Fe9  1  0.066  0.066  0.000  1.0
  Fe  Fe10  1  0.440  0.440  0.000  1.0
  Fe  Fe11  1  0.934  0.934  0.000  1.0
  Cu  Cu12  1  0.306  0.306  0.000  1.0
  Cu  Cu13  1  0.806  0.806  0.000  1.0
  Cu  Cu14  1  0.194  0.194  0.000  1.0
  Cu  Cu15  1  0.694  0.694  0.000  1.0
  O  O16  1  0.292  0.292  0.481  1.0
  O  O17  1  0.547  0.547  0.497  1.0
  O  O18  1  0.811  0.811  0.519  1.0
  O  O19  1  0.051  0.051  0.503  1.0
  O  O20  1  0.292  0.811  0.000  1.0
  O  O21  1  0.547  0.051  0.000  1.0
  O  O22  1  0.811  0.292  0.000  1.0
  O  O23  1  0.051  0.547  0.000  1.0
  O  O24  1  0.189  0.189  0.481  1.0
  O  O25  1  0.453  0.453  0.503  1.0
  O  O26  1  0.708  0.708  0.519  1.0
  O  O27  1  0.949  0.949  0.497  1.0
  O  O28  1  0.189  0.708  0.000  1.0
  O  O29  1  0.453  0.949  0.000  1.0
  O  O30  1  0.708  0.189  0.000  1.0
  O  O31  1  0.949  0.453  0.000  1.0
  O  O32  1  0.381  0.381  0.000  1.0
  O  O33  1  0.619  0.619  0.000  1.0
  O  O34  1  0.875  0.875  0.000  1.0
  O  O35  1  0.125  0.125  0.000  1.0
  O  O36  1  0.500  0.500  0.000  1.0
[/CIF]
.