The material described by Pr3Si2S8Br crystallizes in the monoclinic C2/c space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to one S(1), two equivalent S(3), two equivalent S(4), three equivalent S(2), and one Br(1) atom. In the second Pr site, Pr(2) is bonded in a 9-coordinate geometry to two equivalent S(3), two equivalent S(4), four equivalent S(1), and one Br(1) atom. Si(1) is bonded in a tetrahedral geometry to one S(1), one S(2), one S(3), and one S(4) atom. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Pr(1), two equivalent Pr(2), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SPr3Si trigonal pyramids. In the second S site, S(2) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Pr(1) and one Si(1) atom. In the third S site, S(3) is bonded to one Pr(2), two equivalent Pr(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SPr3Si trigonal pyramids. In the fourth S site, S(4) is bonded to one Pr(2), two equivalent Pr(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SPr3Si trigonal pyramids. Br(1) is bonded in a 3-coordinate geometry to one Pr(2) and two equivalent Pr(1) atoms. is represented by the CIF file [CIF]
data_Pr3Si2S8Br
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.852
_cell_length_b   8.852
_cell_length_c   11.005
_cell_angle_alpha   83.185
_cell_angle_beta   83.185
_cell_angle_gamma   52.342
_symmetry_Int_Tables_number   1
_cell_volume   676.635
_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  0.318  0.074  0.316  1.0
  Pr  Pr1  1  0.926  0.682  0.184  1.0
  Pr  Pr2  1  0.610  0.390  0.250  1.0
  Pr  Pr3  1  0.074  0.318  0.816  1.0
  Pr  Pr4  1  0.682  0.926  0.684  1.0
  Pr  Pr5  1  0.390  0.610  0.750  1.0
  Si  Si6  1  0.306  0.374  0.530  1.0
  Si  Si7  1  0.694  0.626  0.470  1.0
  Si  Si8  1  0.374  0.306  0.030  1.0
  Si  Si9  1  0.626  0.694  0.970  1.0
  S  S10  1  0.722  0.411  0.953  1.0
  S  S11  1  0.712  0.854  0.415  1.0
  S  S12  1  0.107  0.602  0.645  1.0
  S  S13  1  0.554  0.742  0.160  1.0
  S  S14  1  0.893  0.398  0.355  1.0
  S  S15  1  0.589  0.278  0.547  1.0
  S  S16  1  0.446  0.258  0.840  1.0
  S  S17  1  0.411  0.722  0.453  1.0
  S  S18  1  0.398  0.893  0.855  1.0
  S  S19  1  0.278  0.589  0.047  1.0
  S  S20  1  0.258  0.446  0.340  1.0
  S  S21  1  0.146  0.288  0.085  1.0
  S  S22  1  0.602  0.107  0.145  1.0
  S  S23  1  0.742  0.554  0.660  1.0
  S  S24  1  0.288  0.146  0.585  1.0
  S  S25  1  0.854  0.712  0.915  1.0
  Br  Br26  1  0.005  0.995  0.250  1.0
  Br  Br27  1  0.995  0.005  0.750  1.0
[/CIF]
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The material described by Pr3Si2S8Br crystallizes in the monoclinic C2/c space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to one S(1), two equivalent S(3), two equivalent S(4), three equivalent S(2), and one Br(1) atom. In the second Pr site, Pr(2) is bonded in a 9-coordinate geometry to two equivalent S(3), two equivalent S(4), four equivalent S(1), and one Br(1) atom. Si(1) is bonded in a tetrahedral geometry to one S(1), one S(2), one S(3), and one S(4) atom. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Pr(1), two equivalent Pr(2), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SPr3Si trigonal pyramids. In the second S site, S(2) is bonded in a distorted rectangular see-saw-like geometry to three equivalent Pr(1) and one Si(1) atom. In the third S site, S(3) is bonded to one Pr(2), two equivalent Pr(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SPr3Si trigonal pyramids. In the fourth S site, S(4) is bonded to one Pr(2), two equivalent Pr(1), and one Si(1) atom to form a mixture of distorted edge and corner-sharing SPr3Si trigonal pyramids. Br(1) is bonded in a 3-coordinate geometry to one Pr(2) and two equivalent Pr(1) atoms. is represented by the CIF file [CIF]
data_Pr3Si2S8Br
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.852
_cell_length_b   8.852
_cell_length_c   11.005
_cell_angle_alpha   83.185
_cell_angle_beta   83.185
_cell_angle_gamma   52.342
_symmetry_Int_Tables_number   1
_cell_volume   676.635
_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  0.318  0.074  0.316  1.0
  Pr  Pr1  1  0.926  0.682  0.184  1.0
  Pr  Pr2  1  0.610  0.390  0.250  1.0
  Pr  Pr3  1  0.074  0.318  0.816  1.0
  Pr  Pr4  1  0.682  0.926  0.684  1.0
  Pr  Pr5  1  0.390  0.610  0.750  1.0
  Si  Si6  1  0.306  0.374  0.530  1.0
  Si  Si7  1  0.694  0.626  0.470  1.0
  Si  Si8  1  0.374  0.306  0.030  1.0
  Si  Si9  1  0.626  0.694  0.970  1.0
  S  S10  1  0.722  0.411  0.953  1.0
  S  S11  1  0.712  0.854  0.415  1.0
  S  S12  1  0.107  0.602  0.645  1.0
  S  S13  1  0.554  0.742  0.160  1.0
  S  S14  1  0.893  0.398  0.355  1.0
  S  S15  1  0.589  0.278  0.547  1.0
  S  S16  1  0.446  0.258  0.840  1.0
  S  S17  1  0.411  0.722  0.453  1.0
  S  S18  1  0.398  0.893  0.855  1.0
  S  S19  1  0.278  0.589  0.047  1.0
  S  S20  1  0.258  0.446  0.340  1.0
  S  S21  1  0.146  0.288  0.085  1.0
  S  S22  1  0.602  0.107  0.145  1.0
  S  S23  1  0.742  0.554  0.660  1.0
  S  S24  1  0.288  0.146  0.585  1.0
  S  S25  1  0.854  0.712  0.915  1.0
  Br  Br26  1  0.005  0.995  0.250  1.0
  Br  Br27  1  0.995  0.005  0.750  1.0
[/CIF]
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