data_ErPa2Al
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.2
_cell_length_b   5.2
_cell_length_c   5.2
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ErPa2Al
_chemical_formula_sum   'Er1 Pa2 Al1'
_cell_volume   99.56
_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
  Er  Er1  1  0.68  0.68  0.68  1.0
  Pa  Pa2  1  0.52  0.52  0.52  1.0
  Pa  Pa3  1  0.84  0.84  0.84  1.0
  Al  Al0  1  0.0  0.0  0.0  1.0

data_ErPa2Al
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.2
_cell_length_b   5.2
_cell_length_c   12.74
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   ErPa2Al
_chemical_formula_sum   'Er3 Pa6 Al3'
_cell_volume   298.67
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Er  Er0  3  0.0  0.0  0.32  1.0
  Pa  Pa1  3  0.0  0.0  0.16  1.0
  Pa  Pa2  3  0.0  0.0  0.48  1.0
  Al  Al3  3  0.0  0.0  0.0  1.0

Er Pa Pa Al
Er Pa Pa Al 0 1 o o o 0 2 o o o 2 3 + + + 
Pa2ErAl crystallizes in the trigonal R3m space group. There are two inequivalent Pa sites. In the first Pa site, Pa(1) is bonded in a single-bond geometry to one Er(1) atom. The Pa(1)-Er(1) bond length is 2.05 Å. In the second Pa site, Pa(2) is bonded in a distorted linear geometry to one Er(1) and one Al(1) atom. The Pa(2)-Er(1) bond length is 2.05 Å. The Pa(2)-Al(1) bond length is 2.05 Å. Er(1) is bonded to one Pa(1), one Pa(2), and three equivalent Al(1) atoms to form distorted ErPa2Al3 trigonal bipyramids that share corners with six equivalent Er(1)Pa2Al3 trigonal bipyramids and  a cornercorner with one Al(1)Er3Pa trigonal pyramid. All Er(1)-Al(1) bond lengths are 3.01 Å. Al(1) is bonded to one Pa(2) and three equivalent Er(1) atoms to form distorted AlEr3Pa trigonal pyramids that share  a cornercorner with one Er(1)Pa2Al3 trigonal bipyramid and corners with six equivalent Al(1)Er3Pa trigonal pyramids.