The crystal structure described by PrAl4 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 16-coordinate geometry to two equivalent Al(3), two equivalent Al(4), two equivalent Al(5), two equivalent Al(8), four equivalent Al(6), and four equivalent Al(7) atoms. In the second Pr site, Pr(2) is bonded in a 16-coordinate geometry to one Al(3), one Al(4), two equivalent Al(1), two equivalent Al(2), two equivalent Al(6), two equivalent Al(7), three equivalent Al(5), and three equivalent Al(8) atoms. There are eight inequivalent Al sites. In the first Al site, Al(1) is bonded in a 9-coordinate geometry to four equivalent Pr(2), one Al(2), two equivalent Al(4), and two equivalent Al(5) atoms. In the second Al site, Al(2) is bonded in a 9-coordinate geometry to four equivalent Pr(2), one Al(1), two equivalent Al(3), and two equivalent Al(8) atoms. In the third Al site, Al(3) is bonded to two equivalent Pr(1), two equivalent Pr(2), two equivalent Al(2), two equivalent Al(6), and four equivalent Al(8) atoms to form a mixture of distorted face, corner, and edge-sharing AlPr4Al8 cuboctahedra. In the fourth Al site, Al(4) is bonded to two equivalent Pr(1), two equivalent Pr(2), two equivalent Al(1), two equivalent Al(7), and four equivalent Al(5) atoms to form a mixture of distorted face, corner, and edge-sharing AlPr4Al8 cuboctahedra. In the fifth Al site, Al(5) is bonded to one Pr(1), three equivalent Pr(2), one Al(1), one Al(6), two equivalent Al(4), two equivalent Al(7), and two equivalent Al(8) atoms to form a mixture of distorted face, corner, and edge-sharing AlPr4Al8 cuboctahedra. In the sixth Al site, Al(6) is bonded in a 9-coordinate geometry to two equivalent Pr(1), two equivalent Pr(2), one Al(3), one Al(5), one Al(7), and two equivalent Al(8) atoms. In the seventh Al site, Al(7) is bonded in a 9-coordinate geometry to two equivalent Pr(1), two equivalent Pr(2), one Al(4), one Al(6), one Al(8), and two equivalent Al(5) atoms. In the eighth Al site, Al(8) is bonded to one Pr(1), three equivalent Pr(2), one Al(2), one Al(7), two equivalent Al(3), two equivalent Al(5), and two equivalent Al(6) atoms to form a mixture of distorted face, corner, and edge-sharing AlPr4Al8 cuboctahedra. is represented by the CIF file [CIF]
data_PrAl4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.264
_cell_length_b   4.317
_cell_length_c   6.439
_cell_angle_alpha   109.586
_cell_angle_beta   109.336
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   104.546
_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
  Al  Al0  1  0.613  0.613  0.225  1.0
  Al  Al1  1  0.389  0.389  0.777  1.0
  Al  Al2  1  0.252  0.752  0.504  1.0
  Al  Al3  1  0.750  0.250  0.499  1.0
  Pr  Pr4  1  0.001  0.001  0.001  1.0
[/CIF]
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The crystal structure described by PrAl4 crystallizes in the orthorhombic Imm2 space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 16-coordinate geometry to two equivalent Al(3), two equivalent Al(4), two equivalent Al(5), two equivalent Al(8), four equivalent Al(6), and four equivalent Al(7) atoms. In the second Pr site, Pr(2) is bonded in a 16-coordinate geometry to one Al(3), one Al(4), two equivalent Al(1), two equivalent Al(2), two equivalent Al(6), two equivalent Al(7), three equivalent Al(5), and three equivalent Al(8) atoms. There are eight inequivalent Al sites. In the first Al site, Al(1) is bonded in a 9-coordinate geometry to four equivalent Pr(2), one Al(2), two equivalent Al(4), and two equivalent Al(5) atoms. In the second Al site, Al(2) is bonded in a 9-coordinate geometry to four equivalent Pr(2), one Al(1), two equivalent Al(3), and two equivalent Al(8) atoms. In the third Al site, Al(3) is bonded to two equivalent Pr(1), two equivalent Pr(2), two equivalent Al(2), two equivalent Al(6), and four equivalent Al(8) atoms to form a mixture of distorted face, corner, and edge-sharing AlPr4Al8 cuboctahedra. In the fourth Al site, Al(4) is bonded to two equivalent Pr(1), two equivalent Pr(2), two equivalent Al(1), two equivalent Al(7), and four equivalent Al(5) atoms to form a mixture of distorted face, corner, and edge-sharing AlPr4Al8 cuboctahedra. In the fifth Al site, Al(5) is bonded to one Pr(1), three equivalent Pr(2), one Al(1), one Al(6), two equivalent Al(4), two equivalent Al(7), and two equivalent Al(8) atoms to form a mixture of distorted face, corner, and edge-sharing AlPr4Al8 cuboctahedra. In the sixth Al site, Al(6) is bonded in a 9-coordinate geometry to two equivalent Pr(1), two equivalent Pr(2), one Al(3), one Al(5), one Al(7), and two equivalent Al(8) atoms. In the seventh Al site, Al(7) is bonded in a 9-coordinate geometry to two equivalent Pr(1), two equivalent Pr(2), one Al(4), one Al(6), one Al(8), and two equivalent Al(5) atoms. In the eighth Al site, Al(8) is bonded to one Pr(1), three equivalent Pr(2), one Al(2), one Al(7), two equivalent Al(3), two equivalent Al(5), and two equivalent Al(6) atoms to form a mixture of distorted face, corner, and edge-sharing AlPr4Al8 cuboctahedra. is represented by the CIF file [CIF]
data_PrAl4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.264
_cell_length_b   4.317
_cell_length_c   6.439
_cell_angle_alpha   109.586
_cell_angle_beta   109.336
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   104.546
_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
  Al  Al0  1  0.613  0.613  0.225  1.0
  Al  Al1  1  0.389  0.389  0.777  1.0
  Al  Al2  1  0.252  0.752  0.504  1.0
  Al  Al3  1  0.750  0.250  0.499  1.0
  Pr  Pr4  1  0.001  0.001  0.001  1.0
[/CIF]
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