data_BeCu2As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.63
_cell_length_b   2.63
_cell_length_c   7.45
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   93.47
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BeCu2As
_chemical_formula_sum   'Be1 Cu2 As1'
_cell_volume   51.32
_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
  Be  Be1  1  0.0  0.0  0.0  1.0
  Cu  Cu2  1  0.8  0.0  0.45  1.0
  Cu  Cu3  1  0.8  0.0  1.0  1.0
  As  As0  1  0.0  0.0  0.72  1.0

data_BeCu2As
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.63
_cell_length_b   2.63
_cell_length_c   7.45
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   93.47
_symmetry_Int_Tables_number   1
_chemical_formula_structural   BeCu2As
_chemical_formula_sum   'Be1 Cu2 As1'
_cell_volume   51.32
_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
  Be  Be0  1  0.0  0.0  0.0  1.0
  Cu  Cu1  1  0.8  0.0  0.45  1.0
  Cu  Cu2  1  0.8  0.0  1.0  1.0
  As  As3  1  0.0  0.0  0.72  1.0

Be Cu Cu As
BeCu2As is alpha Niobium phosphide-derived structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one BeCu2As cluster. Be(1) is bonded in a single-bond geometry to one Cu(2) and one As(1) atom. The Be(1)-Cu(2) bond length is 0.52 Å. The Be(1)-As(1) bond length is 2.06 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a distorted single-bond geometry to one As(1) atom. The Cu(1)-As(1) bond length is 2.10 Å. In the second Cu site, Cu(2) is bonded in a single-bond geometry to one Be(1) and one As(1) atom. The Cu(2)-As(1) bond length is 2.10 Å. As(1) is bonded in a 3-coordinate geometry to one Be(1), one Cu(1), and one Cu(2) atom.