The material described by Pr7O12 crystallizes in the trigonal R-3 space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a distorted octahedral geometry to six equivalent O(1) atoms. In the second Pr site, Pr(2) is bonded in a 7-coordinate geometry to three equivalent O(1) and four equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(2) is bonded to four equivalent Pr(2) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the second O site, O(1) is bonded to one Pr(1) and three equivalent Pr(2) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. is represented by the CIF card [CIF]
data_Pr7O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.932
_cell_length_b   6.932
_cell_length_c   6.932
_cell_angle_alpha   99.547
_cell_angle_beta   99.547
_cell_angle_gamma   99.547
_symmetry_Int_Tables_number   1
_cell_volume   317.512
_cell_formula_units_Z   1
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  0.000  0.000  1.0
  Pr  Pr1  1  0.299  0.139  0.608  1.0
  Pr  Pr2  1  0.608  0.299  0.139  1.0
  Pr  Pr3  1  0.139  0.608  0.299  1.0
  Pr  Pr4  1  0.701  0.861  0.392  1.0
  Pr  Pr5  1  0.392  0.701  0.861  1.0
  Pr  Pr6  1  0.861  0.392  0.701  1.0
  O  O7  1  0.941  0.066  0.674  1.0
  O  O8  1  0.674  0.941  0.066  1.0
  O  O9  1  0.066  0.674  0.941  1.0
  O  O10  1  0.059  0.934  0.326  1.0
  O  O11  1  0.326  0.059  0.934  1.0
  O  O12  1  0.934  0.326  0.059  1.0
  O  O13  1  0.560  0.420  0.822  1.0
  O  O14  1  0.822  0.560  0.420  1.0
  O  O15  1  0.420  0.822  0.560  1.0
  O  O16  1  0.440  0.580  0.178  1.0
  O  O17  1  0.178  0.440  0.580  1.0
  O  O18  1  0.580  0.178  0.440  1.0
[/CIF]
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The material described by Pr7O12 crystallizes in the trigonal R-3 space group. There are two inequivalent Pr sites. In the first Pr site, Pr(1) is bonded in a distorted octahedral geometry to six equivalent O(1) atoms. In the second Pr site, Pr(2) is bonded in a 7-coordinate geometry to three equivalent O(1) and four equivalent O(2) atoms. There are two inequivalent O sites. In the first O site, O(2) is bonded to four equivalent Pr(2) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. In the second O site, O(1) is bonded to one Pr(1) and three equivalent Pr(2) atoms to form a mixture of corner and edge-sharing OPr4 tetrahedra. is represented by the CIF card [CIF]
data_Pr7O12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.932
_cell_length_b   6.932
_cell_length_c   6.932
_cell_angle_alpha   99.547
_cell_angle_beta   99.547
_cell_angle_gamma   99.547
_symmetry_Int_Tables_number   1
_cell_volume   317.512
_cell_formula_units_Z   1
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  0.000  0.000  1.0
  Pr  Pr1  1  0.299  0.139  0.608  1.0
  Pr  Pr2  1  0.608  0.299  0.139  1.0
  Pr  Pr3  1  0.139  0.608  0.299  1.0
  Pr  Pr4  1  0.701  0.861  0.392  1.0
  Pr  Pr5  1  0.392  0.701  0.861  1.0
  Pr  Pr6  1  0.861  0.392  0.701  1.0
  O  O7  1  0.941  0.066  0.674  1.0
  O  O8  1  0.674  0.941  0.066  1.0
  O  O9  1  0.066  0.674  0.941  1.0
  O  O10  1  0.059  0.934  0.326  1.0
  O  O11  1  0.326  0.059  0.934  1.0
  O  O12  1  0.934  0.326  0.059  1.0
  O  O13  1  0.560  0.420  0.822  1.0
  O  O14  1  0.822  0.560  0.420  1.0
  O  O15  1  0.420  0.822  0.560  1.0
  O  O16  1  0.440  0.580  0.178  1.0
  O  O17  1  0.178  0.440  0.580  1.0
  O  O18  1  0.580  0.178  0.440  1.0
[/CIF]
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