The structure described by Pr6Ni2Si3 crystallizes in the monoclinic Pm space group. There are twelve inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 5-coordinate geometry to two equivalent Ni(1), one Si(3), and two equivalent Si(4) atoms. In the second Pr site, Pr(2) is bonded in a 5-coordinate geometry to one Ni(2), two equivalent Ni(1), and two equivalent Si(5) atoms. In the third Pr site, Pr(3) is bonded in a 5-coordinate geometry to one Ni(3), two equivalent Ni(1), and two equivalent Si(6) atoms. In the fourth Pr site, Pr(4) is bonded in a 5-coordinate geometry to two equivalent Ni(1), two equivalent Ni(2), and one Si(6) atom. In the fifth Pr site, Pr(5) is bonded in a 5-coordinate geometry to two equivalent Ni(1), two equivalent Ni(3), and one Si(4) atom. In the sixth Pr site, Pr(6) is bonded in a 5-coordinate geometry to two equivalent Ni(1), one Si(5), and two equivalent Si(3) atoms. In the seventh Pr site, Pr(7) is bonded in a 7-coordinate geometry to one Si(3), two equivalent Si(1), two equivalent Si(5), and two equivalent Si(6) atoms. In the eighth Pr site, Pr(8) is bonded in a 7-coordinate geometry to one Ni(2), two equivalent Si(1), two equivalent Si(4), and two equivalent Si(6) atoms. In the ninth Pr site, Pr(9) is bonded in a 7-coordinate geometry to one Ni(3), two equivalent Si(1), two equivalent Si(4), and two equivalent Si(5) atoms. In the tenth Pr site, Pr(10) is bonded in a 7-coordinate geometry to two equivalent Ni(3), one Si(6), two equivalent Si(2), and two equivalent Si(3) atoms. In the eleventh Pr site, Pr(11) is bonded in a 7-coordinate geometry to two equivalent Ni(2), one Si(4), two equivalent Si(2), and two equivalent Si(3) atoms. In the twelfth Pr site, Pr(12) is bonded in a 7-coordinate geometry to two equivalent Ni(2), two equivalent Ni(3), one Si(5), and two equivalent Si(2) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a body-centered cubic geometry to one Pr(1), one Pr(2), one Pr(3), one Pr(4), one Pr(5), one Pr(6), and two equivalent Ni(1) atoms. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to one Pr(2), one Pr(8), two equivalent Pr(11), two equivalent Pr(12), two equivalent Pr(4), and one Si(2) atom. In the third Ni site, Ni(3) is bonded in a 9-coordinate geometry to one Pr(3), one Pr(9), two equivalent Pr(10), two equivalent Pr(12), two equivalent Pr(5), and one Si(2) atom. There are six inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Pr(7), two equivalent Pr(8), two equivalent Pr(9), one Si(4), one Si(5), and one Si(6) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Pr(10), two equivalent Pr(11), two equivalent Pr(12), one Ni(2), one Ni(3), and one Si(3) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Pr(1), one Pr(7), two equivalent Pr(10), two equivalent Pr(11), two equivalent Pr(6), and one Si(2) atom. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Pr(11), one Pr(5), two equivalent Pr(1), two equivalent Pr(8), two equivalent Pr(9), and one Si(1) atom. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to one Pr(12), one Pr(6), two equivalent Pr(2), two equivalent Pr(7), two equivalent Pr(9), and one Si(1) atom. In the sixth Si site, Si(6) is bonded in a 9-coordinate geometry to one Pr(10), one Pr(4), two equivalent Pr(3), two equivalent Pr(7), two equivalent Pr(8), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Pr6Si3Ni2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.571
_cell_length_b   11.956
_cell_length_c   12.044
_cell_angle_alpha   60.273
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   571.634
_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  0.000  0.763  0.225  1.0
  Pr  Pr1  1  0.000  0.234  0.002  1.0
  Pr  Pr2  1  0.000  0.004  0.764  1.0
  Pr  Pr3  1  0.500  0.237  0.770  1.0
  Pr  Pr4  1  0.500  0.767  0.991  1.0
  Pr  Pr5  1  0.500  0.990  0.236  1.0
  Pr  Pr6  1  0.000  0.140  0.374  1.0
  Pr  Pr7  1  0.000  0.378  0.487  1.0
  Pr  Pr8  1  0.000  0.486  0.138  1.0
  Pr  Pr9  1  0.500  0.865  0.619  1.0
  Pr  Pr10  1  0.500  0.617  0.519  1.0
  Pr  Pr11  1  0.500  0.523  0.864  1.0
  Si  Si12  1  0.500  0.334  0.334  1.0
  Si  Si13  1  0.000  0.663  0.672  1.0
  Si  Si14  1  0.000  0.845  0.441  1.0
  Si  Si15  1  0.500  0.559  0.289  1.0
  Si  Si16  1  0.500  0.287  0.156  1.0
  Si  Si17  1  0.500  0.154  0.557  1.0
  Ni  Ni18  1  0.750  0.001  0.997  1.0
  Ni  Ni19  1  0.250  0.001  0.997  1.0
  Ni  Ni20  1  0.000  0.440  0.719  1.0
  Ni  Ni21  1  0.000  0.711  0.849  1.0
[/CIF]
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The structure described by Pr6Ni2Si3 crystallizes in the monoclinic Pm space group. There are twelve inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 5-coordinate geometry to two equivalent Ni(1), one Si(3), and two equivalent Si(4) atoms. In the second Pr site, Pr(2) is bonded in a 5-coordinate geometry to one Ni(2), two equivalent Ni(1), and two equivalent Si(5) atoms. In the third Pr site, Pr(3) is bonded in a 5-coordinate geometry to one Ni(3), two equivalent Ni(1), and two equivalent Si(6) atoms. In the fourth Pr site, Pr(4) is bonded in a 5-coordinate geometry to two equivalent Ni(1), two equivalent Ni(2), and one Si(6) atom. In the fifth Pr site, Pr(5) is bonded in a 5-coordinate geometry to two equivalent Ni(1), two equivalent Ni(3), and one Si(4) atom. In the sixth Pr site, Pr(6) is bonded in a 5-coordinate geometry to two equivalent Ni(1), one Si(5), and two equivalent Si(3) atoms. In the seventh Pr site, Pr(7) is bonded in a 7-coordinate geometry to one Si(3), two equivalent Si(1), two equivalent Si(5), and two equivalent Si(6) atoms. In the eighth Pr site, Pr(8) is bonded in a 7-coordinate geometry to one Ni(2), two equivalent Si(1), two equivalent Si(4), and two equivalent Si(6) atoms. In the ninth Pr site, Pr(9) is bonded in a 7-coordinate geometry to one Ni(3), two equivalent Si(1), two equivalent Si(4), and two equivalent Si(5) atoms. In the tenth Pr site, Pr(10) is bonded in a 7-coordinate geometry to two equivalent Ni(3), one Si(6), two equivalent Si(2), and two equivalent Si(3) atoms. In the eleventh Pr site, Pr(11) is bonded in a 7-coordinate geometry to two equivalent Ni(2), one Si(4), two equivalent Si(2), and two equivalent Si(3) atoms. In the twelfth Pr site, Pr(12) is bonded in a 7-coordinate geometry to two equivalent Ni(2), two equivalent Ni(3), one Si(5), and two equivalent Si(2) atoms. There are three inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a body-centered cubic geometry to one Pr(1), one Pr(2), one Pr(3), one Pr(4), one Pr(5), one Pr(6), and two equivalent Ni(1) atoms. In the second Ni site, Ni(2) is bonded in a 9-coordinate geometry to one Pr(2), one Pr(8), two equivalent Pr(11), two equivalent Pr(12), two equivalent Pr(4), and one Si(2) atom. In the third Ni site, Ni(3) is bonded in a 9-coordinate geometry to one Pr(3), one Pr(9), two equivalent Pr(10), two equivalent Pr(12), two equivalent Pr(5), and one Si(2) atom. There are six inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Pr(7), two equivalent Pr(8), two equivalent Pr(9), one Si(4), one Si(5), and one Si(6) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Pr(10), two equivalent Pr(11), two equivalent Pr(12), one Ni(2), one Ni(3), and one Si(3) atom. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to one Pr(1), one Pr(7), two equivalent Pr(10), two equivalent Pr(11), two equivalent Pr(6), and one Si(2) atom. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to one Pr(11), one Pr(5), two equivalent Pr(1), two equivalent Pr(8), two equivalent Pr(9), and one Si(1) atom. In the fifth Si site, Si(5) is bonded in a 9-coordinate geometry to one Pr(12), one Pr(6), two equivalent Pr(2), two equivalent Pr(7), two equivalent Pr(9), and one Si(1) atom. In the sixth Si site, Si(6) is bonded in a 9-coordinate geometry to one Pr(10), one Pr(4), two equivalent Pr(3), two equivalent Pr(7), two equivalent Pr(8), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Pr6Si3Ni2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.571
_cell_length_b   11.956
_cell_length_c   12.044
_cell_angle_alpha   60.273
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   571.634
_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  0.000  0.763  0.225  1.0
  Pr  Pr1  1  0.000  0.234  0.002  1.0
  Pr  Pr2  1  0.000  0.004  0.764  1.0
  Pr  Pr3  1  0.500  0.237  0.770  1.0
  Pr  Pr4  1  0.500  0.767  0.991  1.0
  Pr  Pr5  1  0.500  0.990  0.236  1.0
  Pr  Pr6  1  0.000  0.140  0.374  1.0
  Pr  Pr7  1  0.000  0.378  0.487  1.0
  Pr  Pr8  1  0.000  0.486  0.138  1.0
  Pr  Pr9  1  0.500  0.865  0.619  1.0
  Pr  Pr10  1  0.500  0.617  0.519  1.0
  Pr  Pr11  1  0.500  0.523  0.864  1.0
  Si  Si12  1  0.500  0.334  0.334  1.0
  Si  Si13  1  0.000  0.663  0.672  1.0
  Si  Si14  1  0.000  0.845  0.441  1.0
  Si  Si15  1  0.500  0.559  0.289  1.0
  Si  Si16  1  0.500  0.287  0.156  1.0
  Si  Si17  1  0.500  0.154  0.557  1.0
  Ni  Ni18  1  0.750  0.001  0.997  1.0
  Ni  Ni19  1  0.250  0.001  0.997  1.0
  Ni  Ni20  1  0.000  0.440  0.719  1.0
  Ni  Ni21  1  0.000  0.711  0.849  1.0
[/CIF]
.