The structure described by Pr3Si2O8Cl 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 O(3), two equivalent O(1), two equivalent O(4), three equivalent O(2), and one Cl(1) atom. In the second Pr site, Pr(2) is bonded in a 9-coordinate geometry to two equivalent O(1), two equivalent O(4), four equivalent O(3), and one Cl(1) atom. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Pr(2), two equivalent Pr(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Pr(1) and one Si(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Pr(1), two equivalent Pr(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Pr(2), two equivalent Pr(1), and one Si(1) atom. Cl(1) is bonded in a distorted T-shaped geometry to one Pr(2) and two equivalent Pr(1) atoms. is represented by the CIF file [CIF]
data_Pr3Si2ClO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.827
_cell_length_b   7.827
_cell_length_c   8.823
_cell_angle_alpha   82.425
_cell_angle_beta   82.425
_cell_angle_gamma   48.760
_symmetry_Int_Tables_number   1
_cell_volume   402.191
_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  0.709  0.920  0.171  1.0
  Pr  Pr1  1  0.920  0.709  0.671  1.0
  Pr  Pr2  1  0.573  0.427  0.750  1.0
  Pr  Pr3  1  0.291  0.080  0.829  1.0
  Pr  Pr4  1  0.080  0.291  0.329  1.0
  Pr  Pr5  1  0.427  0.573  0.250  1.0
  Si  Si6  1  0.396  0.288  0.526  1.0
  Si  Si7  1  0.604  0.712  0.474  1.0
  Si  Si8  1  0.712  0.604  0.974  1.0
  Si  Si9  1  0.288  0.396  0.026  1.0
  Cl  Cl10  1  0.025  0.975  0.750  1.0
  Cl  Cl11  1  0.975  0.025  0.250  1.0
  O  O12  1  0.767  0.542  0.154  1.0
  O  O13  1  0.233  0.458  0.846  1.0
  O  O14  1  0.703  0.819  0.919  1.0
  O  O15  1  0.548  0.297  0.033  1.0
  O  O16  1  0.181  0.297  0.581  1.0
  O  O17  1  0.542  0.767  0.654  1.0
  O  O18  1  0.592  0.118  0.646  1.0
  O  O19  1  0.297  0.181  0.081  1.0
  O  O20  1  0.819  0.703  0.419  1.0
  O  O21  1  0.408  0.882  0.354  1.0
  O  O22  1  0.458  0.233  0.346  1.0
  O  O23  1  0.703  0.452  0.467  1.0
  O  O24  1  0.118  0.592  0.146  1.0
  O  O25  1  0.882  0.408  0.854  1.0
  O  O26  1  0.297  0.548  0.533  1.0
  O  O27  1  0.452  0.703  0.967  1.0
[/CIF]
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The structure described by Pr3Si2O8Cl 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 O(3), two equivalent O(1), two equivalent O(4), three equivalent O(2), and one Cl(1) atom. In the second Pr site, Pr(2) is bonded in a 9-coordinate geometry to two equivalent O(1), two equivalent O(4), four equivalent O(3), and one Cl(1) atom. Si(1) is bonded in a tetrahedral geometry to one O(1), one O(2), one O(3), and one O(4) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Pr(2), two equivalent Pr(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to three equivalent Pr(1) and one Si(1) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Pr(1), two equivalent Pr(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Pr(2), two equivalent Pr(1), and one Si(1) atom. Cl(1) is bonded in a distorted T-shaped geometry to one Pr(2) and two equivalent Pr(1) atoms. is represented by the CIF file [CIF]
data_Pr3Si2ClO8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.827
_cell_length_b   7.827
_cell_length_c   8.823
_cell_angle_alpha   82.425
_cell_angle_beta   82.425
_cell_angle_gamma   48.760
_symmetry_Int_Tables_number   1
_cell_volume   402.191
_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  0.709  0.920  0.171  1.0
  Pr  Pr1  1  0.920  0.709  0.671  1.0
  Pr  Pr2  1  0.573  0.427  0.750  1.0
  Pr  Pr3  1  0.291  0.080  0.829  1.0
  Pr  Pr4  1  0.080  0.291  0.329  1.0
  Pr  Pr5  1  0.427  0.573  0.250  1.0
  Si  Si6  1  0.396  0.288  0.526  1.0
  Si  Si7  1  0.604  0.712  0.474  1.0
  Si  Si8  1  0.712  0.604  0.974  1.0
  Si  Si9  1  0.288  0.396  0.026  1.0
  Cl  Cl10  1  0.025  0.975  0.750  1.0
  Cl  Cl11  1  0.975  0.025  0.250  1.0
  O  O12  1  0.767  0.542  0.154  1.0
  O  O13  1  0.233  0.458  0.846  1.0
  O  O14  1  0.703  0.819  0.919  1.0
  O  O15  1  0.548  0.297  0.033  1.0
  O  O16  1  0.181  0.297  0.581  1.0
  O  O17  1  0.542  0.767  0.654  1.0
  O  O18  1  0.592  0.118  0.646  1.0
  O  O19  1  0.297  0.181  0.081  1.0
  O  O20  1  0.819  0.703  0.419  1.0
  O  O21  1  0.408  0.882  0.354  1.0
  O  O22  1  0.458  0.233  0.346  1.0
  O  O23  1  0.703  0.452  0.467  1.0
  O  O24  1  0.118  0.592  0.146  1.0
  O  O25  1  0.882  0.408  0.854  1.0
  O  O26  1  0.297  0.548  0.533  1.0
  O  O27  1  0.452  0.703  0.967  1.0
[/CIF]
.