The compound described by PrNi9Si2 crystallizes in the tetragonal I4_1/amd space group. Pr(1) is bonded in a 18-coordinate geometry to two equivalent Ni(1) and sixteen equivalent Ni(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 14-coordinate geometry to two equivalent Pr(1), eight equivalent Ni(2), and four equivalent Si(1) atoms. In the second Ni site, Ni(2) is bonded to two equivalent Pr(1), one Ni(1), seven equivalent Ni(2), and two equivalent Si(1) atoms to form a mixture of distorted face, edge, and corner-sharing NiPr2Si2Ni8 cuboctahedra. Si(1) is bonded in a 10-coordinate geometry to two equivalent Ni(1) and eight equivalent Ni(2) atoms. is represented by the CIF file [CIF]
data_PrSi2Ni9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.550
_cell_length_b   7.550
_cell_length_c   7.549
_cell_angle_alpha   99.573
_cell_angle_beta   99.573
_cell_angle_gamma   131.858
_symmetry_Int_Tables_number   1
_cell_volume   292.598
_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
  Pr  Pr0  1  0.500  0.500  0.000  1.0
  Pr  Pr1  1  0.750  0.250  0.500  1.0
  Si  Si2  1  0.625  0.875  0.750  1.0
  Si  Si3  1  0.125  0.375  0.250  1.0
  Si  Si4  1  0.125  0.875  0.750  1.0
  Si  Si5  1  0.125  0.875  0.250  1.0
  Ni  Ni6  1  0.250  0.750  0.500  1.0
  Ni  Ni7  1  0.000  1.000  0.000  1.0
  Ni  Ni8  1  0.689  0.018  0.078  1.0
  Ni  Ni9  1  0.689  0.611  0.671  1.0
  Ni  Ni10  1  0.268  0.439  0.578  1.0
  Ni  Ni11  1  0.268  0.689  0.829  1.0
  Ni  Ni12  1  0.939  0.018  0.329  1.0
  Ni  Ni13  1  0.939  0.610  0.922  1.0
  Ni  Ni14  1  0.861  0.439  0.171  1.0
  Ni  Ni15  1  0.860  0.689  0.422  1.0
  Ni  Ni16  1  0.561  0.732  0.422  1.0
  Ni  Ni17  1  0.561  0.139  0.829  1.0
  Ni  Ni18  1  0.982  0.311  0.922  1.0
  Ni  Ni19  1  0.982  0.061  0.671  1.0
  Ni  Ni20  1  0.311  0.732  0.171  1.0
  Ni  Ni21  1  0.311  0.140  0.578  1.0
  Ni  Ni22  1  0.389  0.311  0.329  1.0
  Ni  Ni23  1  0.390  0.061  0.078  1.0
[/CIF]
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The compound described by PrNi9Si2 crystallizes in the tetragonal I4_1/amd space group. Pr(1) is bonded in a 18-coordinate geometry to two equivalent Ni(1) and sixteen equivalent Ni(2) atoms. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 14-coordinate geometry to two equivalent Pr(1), eight equivalent Ni(2), and four equivalent Si(1) atoms. In the second Ni site, Ni(2) is bonded to two equivalent Pr(1), one Ni(1), seven equivalent Ni(2), and two equivalent Si(1) atoms to form a mixture of distorted face, edge, and corner-sharing NiPr2Si2Ni8 cuboctahedra. Si(1) is bonded in a 10-coordinate geometry to two equivalent Ni(1) and eight equivalent Ni(2) atoms. is represented by the CIF file [CIF]
data_PrSi2Ni9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.550
_cell_length_b   7.550
_cell_length_c   7.549
_cell_angle_alpha   99.573
_cell_angle_beta   99.573
_cell_angle_gamma   131.858
_symmetry_Int_Tables_number   1
_cell_volume   292.598
_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
  Pr  Pr0  1  0.500  0.500  0.000  1.0
  Pr  Pr1  1  0.750  0.250  0.500  1.0
  Si  Si2  1  0.625  0.875  0.750  1.0
  Si  Si3  1  0.125  0.375  0.250  1.0
  Si  Si4  1  0.125  0.875  0.750  1.0
  Si  Si5  1  0.125  0.875  0.250  1.0
  Ni  Ni6  1  0.250  0.750  0.500  1.0
  Ni  Ni7  1  0.000  1.000  0.000  1.0
  Ni  Ni8  1  0.689  0.018  0.078  1.0
  Ni  Ni9  1  0.689  0.611  0.671  1.0
  Ni  Ni10  1  0.268  0.439  0.578  1.0
  Ni  Ni11  1  0.268  0.689  0.829  1.0
  Ni  Ni12  1  0.939  0.018  0.329  1.0
  Ni  Ni13  1  0.939  0.610  0.922  1.0
  Ni  Ni14  1  0.861  0.439  0.171  1.0
  Ni  Ni15  1  0.860  0.689  0.422  1.0
  Ni  Ni16  1  0.561  0.732  0.422  1.0
  Ni  Ni17  1  0.561  0.139  0.829  1.0
  Ni  Ni18  1  0.982  0.311  0.922  1.0
  Ni  Ni19  1  0.982  0.061  0.671  1.0
  Ni  Ni20  1  0.311  0.732  0.171  1.0
  Ni  Ni21  1  0.311  0.140  0.578  1.0
  Ni  Ni22  1  0.389  0.311  0.329  1.0
  Ni  Ni23  1  0.390  0.061  0.078  1.0
[/CIF]
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