data_BaEr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.5
_cell_length_b   7.5
_cell_length_c   5.83
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BaEr3
_chemical_formula_sum   'Ba2 Er6'
_cell_volume   284.17
_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
  Ba  Ba0  1  0.0  0.33  0.46  1.0
  Ba  Ba1  1  0.75  0.17  0.37  1.0
  Er  Er2  1  0.0  0.06  0.37  1.0
  Er  Er3  1  0.97  0.47  0.37  1.0
  Er  Er4  1  0.03  0.47  0.37  1.0
  Er  Er5  1  0.75  0.44  0.46  1.0
  Er  Er6  1  0.78  0.03  0.46  1.0
  Er  Er7  1  0.72  0.03  0.46  1.0

data_BaEr3
_symmetry_space_group_name_H-M   P-1
_cell_length_a   5.83
_cell_length_b   7.5
_cell_length_c   7.5
_cell_angle_alpha   120.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   BaEr3
_chemical_formula_sum   'Ba2 Er6'
_cell_volume   284.17
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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
  Ba  Ba0  2  0.04  0.62  0.08  1.0
  Er  Er1  2  0.04  0.34  0.78  1.0
  Er  Er2  2  0.04  0.38  0.19  1.0
  Er  Er3  2  0.04  0.41  0.78  1.0

Ba Ba Er Er Er Er Er Er
BaEr3 is Hg_xSn structured and crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one BaEr3 cluster. Ba(1) is bonded in a 1-coordinate geometry to one Er(1), one Er(3), and two equivalent Er(2) atoms. The Ba(1)-Er(1) bond length is 2.11 Å. The Ba(1)-Er(3) bond length is 1.06 Å. There is one shorter (1.26 Å) and one longer (2.03 Å) Ba(1)-Er(2) bond length. There are three inequivalent Er sites. In the first Er site, Er(1) is bonded in a 2-coordinate geometry to one Ba(1) and one Er(2) atom. The Er(1)-Er(2) bond length is 1.62 Å. In the second Er site, Er(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Er(1), and one Er(3) atom. The Er(2)-Er(3) bond length is 0.46 Å. In the third Er site, Er(3) is bonded in a water-like geometry to one Ba(1) and one Er(2) atom.