The compound described by Pr3Si2O7Cl3 crystallizes in the monoclinic P2_1 space group. There are three inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), one O(7), one Cl(2), and two equivalent Cl(1) atoms. In the second Pr site, Pr(2) is bonded in a 10-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), one Cl(1), two equivalent Cl(2), and two equivalent Cl(3) atoms. In the third Pr site, Pr(3) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(6), one Cl(1), one Cl(2), and two equivalent Cl(3) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(4), one O(5), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Pr(1), one Pr(3), and one Si(2) atom. In the second O site, O(2) is bonded to one Pr(1), one Pr(2), one Pr(3), and one Si(1) atom to form distorted corner-sharing OPr3Si tetrahedra. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Pr(1), one Pr(2), one Pr(3), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Pr(1), one Pr(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Pr(2), one Pr(3), and one Si(1) atom. In the sixth O site, O(6) is bonded to one Pr(1), one Pr(2), one Pr(3), and one Si(2) atom to form distorted corner-sharing OPr3Si tetrahedra. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Pr(1), one Si(1), and one Si(2) atom. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a see-saw-like geometry to one Pr(2), one Pr(3), and two equivalent Pr(1) atoms. In the second Cl site, Cl(2) is bonded in a see-saw-like geometry to one Pr(1), one Pr(3), and two equivalent Pr(2) atoms. In the third Cl site, Cl(3) is bonded in a distorted see-saw-like geometry to two equivalent Pr(2) and two equivalent Pr(3) atoms. is represented by the CIF file [CIF]
data_Pr3Si2Cl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.219
_cell_length_b   5.362
_cell_length_c   7.915
_cell_angle_alpha   71.216
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   490.940
_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  0.102  0.706  0.469  1.0
  Pr  Pr1  1  0.124  0.968  0.921  1.0
  Pr  Pr2  1  0.624  0.032  0.079  1.0
  Pr  Pr3  1  0.378  0.553  0.797  1.0
  Pr  Pr4  1  0.878  0.447  0.203  1.0
  Pr  Pr5  1  0.602  0.294  0.531  1.0
  Si  Si6  1  0.176  0.387  0.183  1.0
  Si  Si7  1  0.789  0.788  0.436  1.0
  Si  Si8  1  0.676  0.613  0.817  1.0
  Si  Si9  1  0.289  0.212  0.564  1.0
  Cl  Cl10  1  0.505  0.845  0.443  1.0
  Cl  Cl11  1  0.509  0.457  0.168  1.0
  Cl  Cl12  1  0.882  0.988  0.992  1.0
  Cl  Cl13  1  0.005  0.155  0.557  1.0
  Cl  Cl14  1  0.382  0.012  0.008  1.0
  Cl  Cl15  1  0.009  0.543  0.832  1.0
  O  O16  1  0.915  0.727  0.402  1.0
  O  O17  1  0.573  0.420  0.803  1.0
  O  O18  1  0.252  0.902  0.621  1.0
  O  O19  1  0.639  0.910  0.808  1.0
  O  O20  1  0.738  0.440  0.999  1.0
  O  O21  1  0.720  0.652  0.307  1.0
  O  O22  1  0.220  0.348  0.693  1.0
  O  O23  1  0.748  0.617  0.639  1.0
  O  O24  1  0.752  0.098  0.379  1.0
  O  O25  1  0.248  0.383  0.361  1.0
  O  O26  1  0.073  0.580  0.197  1.0
  O  O27  1  0.139  0.090  0.192  1.0
  O  O28  1  0.238  0.560  0.001  1.0
  O  O29  1  0.415  0.273  0.598  1.0
[/CIF]
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The compound described by Pr3Si2O7Cl3 crystallizes in the monoclinic P2_1 space group. There are three inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(6), one O(7), one Cl(2), and two equivalent Cl(1) atoms. In the second Pr site, Pr(2) is bonded in a 10-coordinate geometry to one O(2), one O(3), one O(4), one O(5), one O(6), one Cl(1), two equivalent Cl(2), and two equivalent Cl(3) atoms. In the third Pr site, Pr(3) is bonded in a 9-coordinate geometry to one O(1), one O(2), one O(3), one O(5), one O(6), one Cl(1), one Cl(2), and two equivalent Cl(3) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(2), one O(4), one O(5), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(3), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Pr(1), one Pr(3), and one Si(2) atom. In the second O site, O(2) is bonded to one Pr(1), one Pr(2), one Pr(3), and one Si(1) atom to form distorted corner-sharing OPr3Si tetrahedra. In the third O site, O(3) is bonded in a 1-coordinate geometry to one Pr(1), one Pr(2), one Pr(3), and one Si(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Pr(1), one Pr(2), and one Si(1) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Pr(2), one Pr(3), and one Si(1) atom. In the sixth O site, O(6) is bonded to one Pr(1), one Pr(2), one Pr(3), and one Si(2) atom to form distorted corner-sharing OPr3Si tetrahedra. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Pr(1), one Si(1), and one Si(2) atom. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded in a see-saw-like geometry to one Pr(2), one Pr(3), and two equivalent Pr(1) atoms. In the second Cl site, Cl(2) is bonded in a see-saw-like geometry to one Pr(1), one Pr(3), and two equivalent Pr(2) atoms. In the third Cl site, Cl(3) is bonded in a distorted see-saw-like geometry to two equivalent Pr(2) and two equivalent Pr(3) atoms. is represented by the CIF file [CIF]
data_Pr3Si2Cl3O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.219
_cell_length_b   5.362
_cell_length_c   7.915
_cell_angle_alpha   71.216
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   490.940
_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  0.102  0.706  0.469  1.0
  Pr  Pr1  1  0.124  0.968  0.921  1.0
  Pr  Pr2  1  0.624  0.032  0.079  1.0
  Pr  Pr3  1  0.378  0.553  0.797  1.0
  Pr  Pr4  1  0.878  0.447  0.203  1.0
  Pr  Pr5  1  0.602  0.294  0.531  1.0
  Si  Si6  1  0.176  0.387  0.183  1.0
  Si  Si7  1  0.789  0.788  0.436  1.0
  Si  Si8  1  0.676  0.613  0.817  1.0
  Si  Si9  1  0.289  0.212  0.564  1.0
  Cl  Cl10  1  0.505  0.845  0.443  1.0
  Cl  Cl11  1  0.509  0.457  0.168  1.0
  Cl  Cl12  1  0.882  0.988  0.992  1.0
  Cl  Cl13  1  0.005  0.155  0.557  1.0
  Cl  Cl14  1  0.382  0.012  0.008  1.0
  Cl  Cl15  1  0.009  0.543  0.832  1.0
  O  O16  1  0.915  0.727  0.402  1.0
  O  O17  1  0.573  0.420  0.803  1.0
  O  O18  1  0.252  0.902  0.621  1.0
  O  O19  1  0.639  0.910  0.808  1.0
  O  O20  1  0.738  0.440  0.999  1.0
  O  O21  1  0.720  0.652  0.307  1.0
  O  O22  1  0.220  0.348  0.693  1.0
  O  O23  1  0.748  0.617  0.639  1.0
  O  O24  1  0.752  0.098  0.379  1.0
  O  O25  1  0.248  0.383  0.361  1.0
  O  O26  1  0.073  0.580  0.197  1.0
  O  O27  1  0.139  0.090  0.192  1.0
  O  O28  1  0.238  0.560  0.001  1.0
  O  O29  1  0.415  0.273  0.598  1.0
[/CIF]
.