The material described by Be3Cu crystallizes in the monoclinic Cm space group. There are seven inequivalent Be sites. In the first Be site, Be(1) is bonded to one Be(5), one Be(6), two equivalent Be(7), four equivalent Be(3), one Cu(1), one Cu(3), and two equivalent Cu(2) atoms to form distorted BeBe8Cu4 cuboctahedra that share corners with two equivalent Be(6)Be6Cu6 cuboctahedra, corners with two equivalent Be(2)Be7Cu5 cuboctahedra, corners with two equivalent Be(5)Be9Cu3 cuboctahedra, corners with four equivalent Be(1)Be8Cu4 cuboctahedra, corners with eight equivalent Be(4)Be7Cu5 cuboctahedra, edges with two equivalent Be(1)Be8Cu4 cuboctahedra, edges with four equivalent Be(2)Be7Cu5 cuboctahedra, faces with three equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(5)Be9Cu3 cuboctahedra, faces with four equivalent Be(4)Be7Cu5 cuboctahedra, and faces with eight equivalent Be(3)Be8Cu4 cuboctahedra. In the second Be site, Be(2) is bonded to one Be(5), one Be(6), one Be(7), four equivalent Be(4), one Cu(2), two equivalent Cu(1), and two equivalent Cu(3) atoms to form BeBe7Cu5 cuboctahedra that share corners with two equivalent Be(6)Be6Cu6 cuboctahedra, corners with two equivalent Be(1)Be8Cu4 cuboctahedra, corners with two equivalent Be(5)Be9Cu3 cuboctahedra, corners with four equivalent Be(2)Be7Cu5 cuboctahedra, corners with eight equivalent Be(3)Be8Cu4 cuboctahedra, edges with two equivalent Be(2)Be7Cu5 cuboctahedra, edges with four equivalent Be(1)Be8Cu4 cuboctahedra, faces with three equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(5)Be9Cu3 cuboctahedra, faces with four equivalent Be(3)Be8Cu4 cuboctahedra, and faces with eight equivalent Be(4)Be7Cu5 cuboctahedra. In the third Be site, Be(3) is bonded to one Be(5), one Be(6), two equivalent Be(1), two equivalent Be(3), two equivalent Be(7), one Cu(1), one Cu(3), and two equivalent Cu(2) atoms to form distorted BeBe8Cu4 cuboctahedra that share corners with two equivalent Be(6)Be6Cu6 cuboctahedra, corners with two equivalent Be(5)Be9Cu3 cuboctahedra, corners with four equivalent Be(2)Be7Cu5 cuboctahedra, corners with four equivalent Be(3)Be8Cu4 cuboctahedra, corners with six equivalent Be(4)Be7Cu5 cuboctahedra, edges with two equivalent Be(3)Be8Cu4 cuboctahedra, edges with four equivalent Be(4)Be7Cu5 cuboctahedra, faces with two equivalent Be(2)Be7Cu5 cuboctahedra, faces with two equivalent Be(4)Be7Cu5 cuboctahedra, faces with three equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(5)Be9Cu3 cuboctahedra, faces with four equivalent Be(1)Be8Cu4 cuboctahedra, and faces with four equivalent Be(3)Be8Cu4 cuboctahedra. In the fourth Be site, Be(4) is bonded to one Be(5), one Be(6), one Be(7), two equivalent Be(2), two equivalent Be(4), one Cu(2), two equivalent Cu(1), and two equivalent Cu(3) atoms to form BeBe7Cu5 cuboctahedra that share corners with two equivalent Be(6)Be6Cu6 cuboctahedra, corners with two equivalent Be(5)Be9Cu3 cuboctahedra, corners with four equivalent Be(4)Be7Cu5 cuboctahedra, corners with four equivalent Be(1)Be8Cu4 cuboctahedra, corners with six equivalent Be(3)Be8Cu4 cuboctahedra, edges with two equivalent Be(4)Be7Cu5 cuboctahedra, edges with four equivalent Be(3)Be8Cu4 cuboctahedra, faces with two equivalent Be(1)Be8Cu4 cuboctahedra, faces with two equivalent Be(3)Be8Cu4 cuboctahedra, faces with three equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(5)Be9Cu3 cuboctahedra, faces with four equivalent Be(2)Be7Cu5 cuboctahedra, and faces with four equivalent Be(4)Be7Cu5 cuboctahedra. In the fifth Be site, Be(5) is bonded to one Be(1), one Be(2), two equivalent Be(3), two equivalent Be(4), three equivalent Be(7), and three equivalent Cu(3) atoms to form BeBe9Cu3 cuboctahedra that share corners with two equivalent Be(2)Be7Cu5 cuboctahedra, corners with two equivalent Be(1)Be8Cu4 cuboctahedra, corners with four equivalent Be(4)Be7Cu5 cuboctahedra, corners with four equivalent Be(3)Be8Cu4 cuboctahedra, corners with six equivalent Be(6)Be6Cu6 cuboctahedra, edges with six equivalent Be(5)Be9Cu3 cuboctahedra, faces with three equivalent Be(2)Be7Cu5 cuboctahedra, faces with three equivalent Be(1)Be8Cu4 cuboctahedra, faces with six equivalent Be(4)Be7Cu5 cuboctahedra, and faces with six equivalent Be(3)Be8Cu4 cuboctahedra. In the sixth Be site, Be(6) is bonded to one Be(1), one Be(2), two equivalent Be(3), two equivalent Be(4), three equivalent Cu(1), and three equivalent Cu(2) atoms to form BeBe6Cu6 cuboctahedra that share corners with two equivalent Be(2)Be7Cu5 cuboctahedra, corners with two equivalent Be(1)Be8Cu4 cuboctahedra, corners with four equivalent Be(4)Be7Cu5 cuboctahedra, corners with four equivalent Be(3)Be8Cu4 cuboctahedra, corners with six equivalent Be(5)Be9Cu3 cuboctahedra, edges with six equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(2)Be7Cu5 cuboctahedra, faces with three equivalent Be(1)Be8Cu4 cuboctahedra, faces with six equivalent Be(4)Be7Cu5 cuboctahedra, and faces with six equivalent Be(3)Be8Cu4 cuboctahedra. In the seventh Be site, Be(7) is bonded in a 16-coordinate geometry to one Be(2), two equivalent Be(1), two equivalent Be(4), three equivalent Be(5), four equivalent Be(3), one Cu(2), and three equivalent Cu(3) atoms. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 16-coordinate geometry to one Be(1), two equivalent Be(2), two equivalent Be(3), three equivalent Be(6), four equivalent Be(4), one Cu(3), and three equivalent Cu(2) atoms. In the second Cu site, Cu(2) is bonded in a 16-coordinate geometry to one Be(2), one Be(7), two equivalent Be(1), two equivalent Be(4), three equivalent Be(6), four equivalent Be(3), and three equivalent Cu(1) atoms. In the third Cu site, Cu(3) is bonded in a 16-coordinate geometry to one Be(1), two equivalent Be(2), two equivalent Be(3), three equivalent Be(5), three equivalent Be(7), four equivalent Be(4), and one Cu(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Be3Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.187
_cell_length_b   4.187
_cell_length_c   7.251
_cell_angle_alpha   73.228
_cell_angle_beta   89.994
_cell_angle_gamma   120.006
_symmetry_Int_Tables_number   1
_cell_volume   103.798
_cell_formula_units_Z   3
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  0.437  0.375  0.188  1.0
  Be  Be1  1  0.939  0.376  0.686  1.0
  Be  Be2  1  0.436  0.875  0.189  1.0
  Be  Be3  1  0.939  0.876  0.685  1.0
  Be  Be4  1  0.188  0.375  0.437  1.0
  Be  Be5  1  0.688  0.375  0.938  1.0
  Be  Be6  1  0.936  0.375  0.189  1.0
  Be  Be7  1  0.439  0.376  0.685  1.0
  Be  Be8  1  0.875  0.749  0.376  1.0
  Cu  Cu9  1  0.375  0.750  0.874  1.0
  Cu  Cu10  1  0.997  0.994  0.009  1.0
  Cu  Cu11  1  0.502  0.004  0.494  1.0
[/CIF]
.
The material described by Be3Cu crystallizes in the monoclinic Cm space group. There are seven inequivalent Be sites. In the first Be site, Be(1) is bonded to one Be(5), one Be(6), two equivalent Be(7), four equivalent Be(3), one Cu(1), one Cu(3), and two equivalent Cu(2) atoms to form distorted BeBe8Cu4 cuboctahedra that share corners with two equivalent Be(6)Be6Cu6 cuboctahedra, corners with two equivalent Be(2)Be7Cu5 cuboctahedra, corners with two equivalent Be(5)Be9Cu3 cuboctahedra, corners with four equivalent Be(1)Be8Cu4 cuboctahedra, corners with eight equivalent Be(4)Be7Cu5 cuboctahedra, edges with two equivalent Be(1)Be8Cu4 cuboctahedra, edges with four equivalent Be(2)Be7Cu5 cuboctahedra, faces with three equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(5)Be9Cu3 cuboctahedra, faces with four equivalent Be(4)Be7Cu5 cuboctahedra, and faces with eight equivalent Be(3)Be8Cu4 cuboctahedra. In the second Be site, Be(2) is bonded to one Be(5), one Be(6), one Be(7), four equivalent Be(4), one Cu(2), two equivalent Cu(1), and two equivalent Cu(3) atoms to form BeBe7Cu5 cuboctahedra that share corners with two equivalent Be(6)Be6Cu6 cuboctahedra, corners with two equivalent Be(1)Be8Cu4 cuboctahedra, corners with two equivalent Be(5)Be9Cu3 cuboctahedra, corners with four equivalent Be(2)Be7Cu5 cuboctahedra, corners with eight equivalent Be(3)Be8Cu4 cuboctahedra, edges with two equivalent Be(2)Be7Cu5 cuboctahedra, edges with four equivalent Be(1)Be8Cu4 cuboctahedra, faces with three equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(5)Be9Cu3 cuboctahedra, faces with four equivalent Be(3)Be8Cu4 cuboctahedra, and faces with eight equivalent Be(4)Be7Cu5 cuboctahedra. In the third Be site, Be(3) is bonded to one Be(5), one Be(6), two equivalent Be(1), two equivalent Be(3), two equivalent Be(7), one Cu(1), one Cu(3), and two equivalent Cu(2) atoms to form distorted BeBe8Cu4 cuboctahedra that share corners with two equivalent Be(6)Be6Cu6 cuboctahedra, corners with two equivalent Be(5)Be9Cu3 cuboctahedra, corners with four equivalent Be(2)Be7Cu5 cuboctahedra, corners with four equivalent Be(3)Be8Cu4 cuboctahedra, corners with six equivalent Be(4)Be7Cu5 cuboctahedra, edges with two equivalent Be(3)Be8Cu4 cuboctahedra, edges with four equivalent Be(4)Be7Cu5 cuboctahedra, faces with two equivalent Be(2)Be7Cu5 cuboctahedra, faces with two equivalent Be(4)Be7Cu5 cuboctahedra, faces with three equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(5)Be9Cu3 cuboctahedra, faces with four equivalent Be(1)Be8Cu4 cuboctahedra, and faces with four equivalent Be(3)Be8Cu4 cuboctahedra. In the fourth Be site, Be(4) is bonded to one Be(5), one Be(6), one Be(7), two equivalent Be(2), two equivalent Be(4), one Cu(2), two equivalent Cu(1), and two equivalent Cu(3) atoms to form BeBe7Cu5 cuboctahedra that share corners with two equivalent Be(6)Be6Cu6 cuboctahedra, corners with two equivalent Be(5)Be9Cu3 cuboctahedra, corners with four equivalent Be(4)Be7Cu5 cuboctahedra, corners with four equivalent Be(1)Be8Cu4 cuboctahedra, corners with six equivalent Be(3)Be8Cu4 cuboctahedra, edges with two equivalent Be(4)Be7Cu5 cuboctahedra, edges with four equivalent Be(3)Be8Cu4 cuboctahedra, faces with two equivalent Be(1)Be8Cu4 cuboctahedra, faces with two equivalent Be(3)Be8Cu4 cuboctahedra, faces with three equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(5)Be9Cu3 cuboctahedra, faces with four equivalent Be(2)Be7Cu5 cuboctahedra, and faces with four equivalent Be(4)Be7Cu5 cuboctahedra. In the fifth Be site, Be(5) is bonded to one Be(1), one Be(2), two equivalent Be(3), two equivalent Be(4), three equivalent Be(7), and three equivalent Cu(3) atoms to form BeBe9Cu3 cuboctahedra that share corners with two equivalent Be(2)Be7Cu5 cuboctahedra, corners with two equivalent Be(1)Be8Cu4 cuboctahedra, corners with four equivalent Be(4)Be7Cu5 cuboctahedra, corners with four equivalent Be(3)Be8Cu4 cuboctahedra, corners with six equivalent Be(6)Be6Cu6 cuboctahedra, edges with six equivalent Be(5)Be9Cu3 cuboctahedra, faces with three equivalent Be(2)Be7Cu5 cuboctahedra, faces with three equivalent Be(1)Be8Cu4 cuboctahedra, faces with six equivalent Be(4)Be7Cu5 cuboctahedra, and faces with six equivalent Be(3)Be8Cu4 cuboctahedra. In the sixth Be site, Be(6) is bonded to one Be(1), one Be(2), two equivalent Be(3), two equivalent Be(4), three equivalent Cu(1), and three equivalent Cu(2) atoms to form BeBe6Cu6 cuboctahedra that share corners with two equivalent Be(2)Be7Cu5 cuboctahedra, corners with two equivalent Be(1)Be8Cu4 cuboctahedra, corners with four equivalent Be(4)Be7Cu5 cuboctahedra, corners with four equivalent Be(3)Be8Cu4 cuboctahedra, corners with six equivalent Be(5)Be9Cu3 cuboctahedra, edges with six equivalent Be(6)Be6Cu6 cuboctahedra, faces with three equivalent Be(2)Be7Cu5 cuboctahedra, faces with three equivalent Be(1)Be8Cu4 cuboctahedra, faces with six equivalent Be(4)Be7Cu5 cuboctahedra, and faces with six equivalent Be(3)Be8Cu4 cuboctahedra. In the seventh Be site, Be(7) is bonded in a 16-coordinate geometry to one Be(2), two equivalent Be(1), two equivalent Be(4), three equivalent Be(5), four equivalent Be(3), one Cu(2), and three equivalent Cu(3) atoms. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 16-coordinate geometry to one Be(1), two equivalent Be(2), two equivalent Be(3), three equivalent Be(6), four equivalent Be(4), one Cu(3), and three equivalent Cu(2) atoms. In the second Cu site, Cu(2) is bonded in a 16-coordinate geometry to one Be(2), one Be(7), two equivalent Be(1), two equivalent Be(4), three equivalent Be(6), four equivalent Be(3), and three equivalent Cu(1) atoms. In the third Cu site, Cu(3) is bonded in a 16-coordinate geometry to one Be(1), two equivalent Be(2), two equivalent Be(3), three equivalent Be(5), three equivalent Be(7), four equivalent Be(4), and one Cu(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Be3Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.187
_cell_length_b   4.187
_cell_length_c   7.251
_cell_angle_alpha   73.228
_cell_angle_beta   89.994
_cell_angle_gamma   120.006
_symmetry_Int_Tables_number   1
_cell_volume   103.798
_cell_formula_units_Z   3
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  0.437  0.375  0.188  1.0
  Be  Be1  1  0.939  0.376  0.686  1.0
  Be  Be2  1  0.436  0.875  0.189  1.0
  Be  Be3  1  0.939  0.876  0.685  1.0
  Be  Be4  1  0.188  0.375  0.437  1.0
  Be  Be5  1  0.688  0.375  0.938  1.0
  Be  Be6  1  0.936  0.375  0.189  1.0
  Be  Be7  1  0.439  0.376  0.685  1.0
  Be  Be8  1  0.875  0.749  0.376  1.0
  Cu  Cu9  1  0.375  0.750  0.874  1.0
  Cu  Cu10  1  0.997  0.994  0.009  1.0
  Cu  Cu11  1  0.502  0.004  0.494  1.0
[/CIF]
.