data_Eu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.96
_cell_length_b   3.96
_cell_length_c   6.55
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Eu
_chemical_formula_sum   Eu2
_cell_volume   88.91
_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
  Eu  Eu0  1  0.0  0.29  0.64  1.0
  Eu  Eu1  1  0.98  0.14  0.91  1.0

data_Eu
_symmetry_space_group_name_H-M   P-1
_cell_length_a   3.96
_cell_length_b   3.96
_cell_length_c   6.55
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   2
_chemical_formula_structural   Eu
_chemical_formula_sum   Eu2
_cell_volume   88.91
_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
  Eu  Eu0  2  0.49  0.93  0.64  1.0

Eu Eu
Eu is alpha U structured and crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of one Eu cluster. Eu(1) is bonded in a single-bond geometry to one Eu(1) atom. The Eu(1)-Eu(1) bond length is 1.88 Å.