The structure described by PmSc3 is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. Pm(1) is bonded to four equivalent Sc(2) and eight equivalent Sc(1) atoms to form PmSc12 cuboctahedra that share corners with four equivalent Pm(1)Sc12 cuboctahedra, corners with eight equivalent Sc(2)Pm4Sc8 cuboctahedra, edges with eight equivalent Pm(1)Sc12 cuboctahedra, edges with sixteen equivalent Sc(1)Pm4Sc8 cuboctahedra, faces with four equivalent Pm(1)Sc12 cuboctahedra, faces with six equivalent Sc(2)Pm4Sc8 cuboctahedra, and faces with eight equivalent Sc(1)Pm4Sc8 cuboctahedra. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to four equivalent Pm(1), four equivalent Sc(1), and four equivalent Sc(2) atoms to form distorted ScPm4Sc8 cuboctahedra that share corners with twelve equivalent Sc(1)Pm4Sc8 cuboctahedra, edges with eight equivalent Pm(1)Sc12 cuboctahedra, edges with eight equivalent Sc(1)Pm4Sc8 cuboctahedra, edges with eight equivalent Sc(2)Pm4Sc8 cuboctahedra, faces with four equivalent Pm(1)Sc12 cuboctahedra, faces with four equivalent Sc(2)Pm4Sc8 cuboctahedra, and faces with ten equivalent Sc(1)Pm4Sc8 cuboctahedra. In the second Sc site, Sc(2) is bonded to four equivalent Pm(1) and eight equivalent Sc(1) atoms to form ScPm4Sc8 cuboctahedra that share corners with four equivalent Sc(2)Pm4Sc8 cuboctahedra, corners with eight equivalent Pm(1)Sc12 cuboctahedra, edges with eight equivalent Sc(2)Pm4Sc8 cuboctahedra, edges with sixteen equivalent Sc(1)Pm4Sc8 cuboctahedra, faces with four equivalent Sc(2)Pm4Sc8 cuboctahedra, faces with six equivalent Pm(1)Sc12 cuboctahedra, and faces with eight equivalent Sc(1)Pm4Sc8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_PmSc3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.704
_cell_length_b   5.704
_cell_length_c   5.704
_cell_angle_alpha   129.203
_cell_angle_beta   129.203
_cell_angle_gamma   74.684
_symmetry_Int_Tables_number   1
_cell_volume   108.566
_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
  Pm  Pm0  1  0.000  0.000  0.000  1.0
  Sc  Sc1  1  0.750  0.250  0.500  1.0
  Sc  Sc2  1  0.250  0.750  0.500  1.0
  Sc  Sc3  1  0.500  0.500  0.000  1.0
[/CIF]
.
The structure described by PmSc3 is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. Pm(1) is bonded to four equivalent Sc(2) and eight equivalent Sc(1) atoms to form PmSc12 cuboctahedra that share corners with four equivalent Pm(1)Sc12 cuboctahedra, corners with eight equivalent Sc(2)Pm4Sc8 cuboctahedra, edges with eight equivalent Pm(1)Sc12 cuboctahedra, edges with sixteen equivalent Sc(1)Pm4Sc8 cuboctahedra, faces with four equivalent Pm(1)Sc12 cuboctahedra, faces with six equivalent Sc(2)Pm4Sc8 cuboctahedra, and faces with eight equivalent Sc(1)Pm4Sc8 cuboctahedra. There are two inequivalent Sc sites. In the first Sc site, Sc(1) is bonded to four equivalent Pm(1), four equivalent Sc(1), and four equivalent Sc(2) atoms to form distorted ScPm4Sc8 cuboctahedra that share corners with twelve equivalent Sc(1)Pm4Sc8 cuboctahedra, edges with eight equivalent Pm(1)Sc12 cuboctahedra, edges with eight equivalent Sc(1)Pm4Sc8 cuboctahedra, edges with eight equivalent Sc(2)Pm4Sc8 cuboctahedra, faces with four equivalent Pm(1)Sc12 cuboctahedra, faces with four equivalent Sc(2)Pm4Sc8 cuboctahedra, and faces with ten equivalent Sc(1)Pm4Sc8 cuboctahedra. In the second Sc site, Sc(2) is bonded to four equivalent Pm(1) and eight equivalent Sc(1) atoms to form ScPm4Sc8 cuboctahedra that share corners with four equivalent Sc(2)Pm4Sc8 cuboctahedra, corners with eight equivalent Pm(1)Sc12 cuboctahedra, edges with eight equivalent Sc(2)Pm4Sc8 cuboctahedra, edges with sixteen equivalent Sc(1)Pm4Sc8 cuboctahedra, faces with four equivalent Sc(2)Pm4Sc8 cuboctahedra, faces with six equivalent Pm(1)Sc12 cuboctahedra, and faces with eight equivalent Sc(1)Pm4Sc8 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_PmSc3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.704
_cell_length_b   5.704
_cell_length_c   5.704
_cell_angle_alpha   129.203
_cell_angle_beta   129.203
_cell_angle_gamma   74.684
_symmetry_Int_Tables_number   1
_cell_volume   108.566
_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
  Pm  Pm0  1  0.000  0.000  0.000  1.0
  Sc  Sc1  1  0.750  0.250  0.500  1.0
  Sc  Sc2  1  0.250  0.750  0.500  1.0
  Sc  Sc3  1  0.500  0.500  0.000  1.0
[/CIF]
.