The structure described by Pr5CuSe8 crystallizes in the tetragonal I-4 space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. Cu(1) is bonded in a square co-planar geometry to four equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Pr(2) and four equivalent Pr(1) atoms to form distorted SePr5 square pyramids that share corners with eight equivalent Se(2)Pr5Cu octahedra, corners with five equivalent Se(1)Pr5 square pyramids, edges with three equivalent Se(2)Pr5Cu octahedra, edges with five equivalent Se(1)Pr5 square pyramids, and faces with two equivalent Se(2)Pr5Cu octahedra. The corner-sharing octahedral tilt angles range from 20-89°. In the second Se site, Se(2) is bonded to one Pr(2), four equivalent Pr(1), and one Cu(1) atom to form distorted SePr5Cu octahedra that share corners with seven equivalent Se(2)Pr5Cu octahedra, corners with eight equivalent Se(1)Pr5 square pyramids, edges with four equivalent Se(2)Pr5Cu octahedra, edges with three equivalent Se(1)Pr5 square pyramids,  a faceface with one Se(2)Pr5Cu octahedra, and faces with two equivalent Se(1)Pr5 square pyramids. The corner-sharing octahedral tilt angles range from 16-48°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Pr5CuSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.754
_cell_length_b   7.754
_cell_length_c   7.754
_cell_angle_alpha   110.348
_cell_angle_beta   110.348
_cell_angle_gamma   107.732
_symmetry_Int_Tables_number   1
_cell_volume   358.697
_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  0.239  0.621  0.122  1.0
  Pr  Pr1  1  0.379  0.502  0.618  1.0
  Pr  Pr2  1  0.498  0.117  0.878  1.0
  Pr  Pr3  1  0.750  0.250  0.500  1.0
  Pr  Pr4  1  0.883  0.761  0.382  1.0
  Cu  Cu5  1  0.000  0.000  0.000  1.0
  Se  Se6  1  0.606  0.865  0.104  1.0
  Se  Se7  1  0.652  0.891  0.630  1.0
  Se  Se8  1  0.261  0.022  0.370  1.0
  Se  Se9  1  0.498  0.394  0.259  1.0
  Se  Se10  1  0.761  0.502  0.896  1.0
  Se  Se11  1  0.109  0.739  0.761  1.0
  Se  Se12  1  0.978  0.348  0.239  1.0
  Se  Se13  1  0.135  0.239  0.741  1.0
[/CIF]
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The structure described by Pr5CuSe8 crystallizes in the tetragonal I-4 space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second Pr site, Pr(2) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. Cu(1) is bonded in a square co-planar geometry to four equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Pr(2) and four equivalent Pr(1) atoms to form distorted SePr5 square pyramids that share corners with eight equivalent Se(2)Pr5Cu octahedra, corners with five equivalent Se(1)Pr5 square pyramids, edges with three equivalent Se(2)Pr5Cu octahedra, edges with five equivalent Se(1)Pr5 square pyramids, and faces with two equivalent Se(2)Pr5Cu octahedra. The corner-sharing octahedral tilt angles range from 20-89°. In the second Se site, Se(2) is bonded to one Pr(2), four equivalent Pr(1), and one Cu(1) atom to form distorted SePr5Cu octahedra that share corners with seven equivalent Se(2)Pr5Cu octahedra, corners with eight equivalent Se(1)Pr5 square pyramids, edges with four equivalent Se(2)Pr5Cu octahedra, edges with three equivalent Se(1)Pr5 square pyramids,  a faceface with one Se(2)Pr5Cu octahedra, and faces with two equivalent Se(1)Pr5 square pyramids. The corner-sharing octahedral tilt angles range from 16-48°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Pr5CuSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.754
_cell_length_b   7.754
_cell_length_c   7.754
_cell_angle_alpha   110.348
_cell_angle_beta   110.348
_cell_angle_gamma   107.732
_symmetry_Int_Tables_number   1
_cell_volume   358.697
_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  0.239  0.621  0.122  1.0
  Pr  Pr1  1  0.379  0.502  0.618  1.0
  Pr  Pr2  1  0.498  0.117  0.878  1.0
  Pr  Pr3  1  0.750  0.250  0.500  1.0
  Pr  Pr4  1  0.883  0.761  0.382  1.0
  Cu  Cu5  1  0.000  0.000  0.000  1.0
  Se  Se6  1  0.606  0.865  0.104  1.0
  Se  Se7  1  0.652  0.891  0.630  1.0
  Se  Se8  1  0.261  0.022  0.370  1.0
  Se  Se9  1  0.498  0.394  0.259  1.0
  Se  Se10  1  0.761  0.502  0.896  1.0
  Se  Se11  1  0.109  0.739  0.761  1.0
  Se  Se12  1  0.978  0.348  0.239  1.0
  Se  Se13  1  0.135  0.239  0.741  1.0
[/CIF]
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