The structure described by Be4CrAl crystallizes in the trigonal P-3m1 space group. There are three inequivalent Be sites. In the first Be site, Be(1) is bonded to six equivalent Be(3) and six equivalent Al(1) atoms to form BeBe6Al6 cuboctahedra that share corners with twelve equivalent Be(3)Be6Al3Cr3 cuboctahedra, edges with six equivalent Be(1)Be6Al6 cuboctahedra, faces with two equivalent Be(2)Be6Cr6 cuboctahedra, and faces with eighteen equivalent Be(3)Be6Al3Cr3 cuboctahedra. In the second Be site, Be(2) is bonded to six equivalent Be(3) and six equivalent Cr(1) atoms to form BeBe6Cr6 cuboctahedra that share corners with twelve equivalent Be(3)Be6Al3Cr3 cuboctahedra, edges with six equivalent Be(2)Be6Cr6 cuboctahedra, faces with two equivalent Be(1)Be6Al6 cuboctahedra, and faces with eighteen equivalent Be(3)Be6Al3Cr3 cuboctahedra. In the third Be site, Be(3) is bonded to one Be(1), one Be(2), four equivalent Be(3), three equivalent Cr(1), and three equivalent Al(1) atoms to form BeBe6Al3Cr3 cuboctahedra that share corners with two equivalent Be(1)Be6Al6 cuboctahedra, corners with two equivalent Be(2)Be6Cr6 cuboctahedra, corners with fourteen equivalent Be(3)Be6Al3Cr3 cuboctahedra, edges with six equivalent Be(3)Be6Al3Cr3 cuboctahedra, faces with three equivalent Be(1)Be6Al6 cuboctahedra, faces with three equivalent Be(2)Be6Cr6 cuboctahedra, and faces with twelve equivalent Be(3)Be6Al3Cr3 cuboctahedra. Cr(1) is bonded in a 16-coordinate geometry to three equivalent Be(2), nine equivalent Be(3), three equivalent Cr(1), and one Al(1) atom. Al(1) is bonded in a 16-coordinate geometry to three equivalent Be(1), nine equivalent Be(3), one Cr(1), and three equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_Be4AlCr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.307
_cell_length_b   4.307
_cell_length_c   7.017
_cell_angle_alpha   90.000
_cell_angle_beta   90.001
_cell_angle_gamma   60.003
_symmetry_Int_Tables_number   1
_cell_volume   112.720
_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
  Be  Be0  1  0.000  1.000  0.500  1.0
  Be  Be1  1  0.000  1.000  0.000  1.0
  Be  Be2  1  0.831  0.337  0.759  1.0
  Be  Be3  1  0.337  0.831  0.759  1.0
  Be  Be4  1  0.831  0.831  0.759  1.0
  Be  Be5  1  0.169  0.663  0.241  1.0
  Be  Be6  1  0.663  0.169  0.241  1.0
  Be  Be7  1  0.169  0.169  0.241  1.0
  Al  Al8  1  0.333  0.333  0.578  1.0
  Al  Al9  1  0.667  0.667  0.422  1.0
  Cr  Cr10  1  0.667  0.667  0.052  1.0
  Cr  Cr11  1  0.333  0.333  0.948  1.0
[/CIF]
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The structure described by Be4CrAl crystallizes in the trigonal P-3m1 space group. There are three inequivalent Be sites. In the first Be site, Be(1) is bonded to six equivalent Be(3) and six equivalent Al(1) atoms to form BeBe6Al6 cuboctahedra that share corners with twelve equivalent Be(3)Be6Al3Cr3 cuboctahedra, edges with six equivalent Be(1)Be6Al6 cuboctahedra, faces with two equivalent Be(2)Be6Cr6 cuboctahedra, and faces with eighteen equivalent Be(3)Be6Al3Cr3 cuboctahedra. In the second Be site, Be(2) is bonded to six equivalent Be(3) and six equivalent Cr(1) atoms to form BeBe6Cr6 cuboctahedra that share corners with twelve equivalent Be(3)Be6Al3Cr3 cuboctahedra, edges with six equivalent Be(2)Be6Cr6 cuboctahedra, faces with two equivalent Be(1)Be6Al6 cuboctahedra, and faces with eighteen equivalent Be(3)Be6Al3Cr3 cuboctahedra. In the third Be site, Be(3) is bonded to one Be(1), one Be(2), four equivalent Be(3), three equivalent Cr(1), and three equivalent Al(1) atoms to form BeBe6Al3Cr3 cuboctahedra that share corners with two equivalent Be(1)Be6Al6 cuboctahedra, corners with two equivalent Be(2)Be6Cr6 cuboctahedra, corners with fourteen equivalent Be(3)Be6Al3Cr3 cuboctahedra, edges with six equivalent Be(3)Be6Al3Cr3 cuboctahedra, faces with three equivalent Be(1)Be6Al6 cuboctahedra, faces with three equivalent Be(2)Be6Cr6 cuboctahedra, and faces with twelve equivalent Be(3)Be6Al3Cr3 cuboctahedra. Cr(1) is bonded in a 16-coordinate geometry to three equivalent Be(2), nine equivalent Be(3), three equivalent Cr(1), and one Al(1) atom. Al(1) is bonded in a 16-coordinate geometry to three equivalent Be(1), nine equivalent Be(3), one Cr(1), and three equivalent Al(1) atoms. is represented by the CIF file [CIF]
data_Be4AlCr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.307
_cell_length_b   4.307
_cell_length_c   7.017
_cell_angle_alpha   90.000
_cell_angle_beta   90.001
_cell_angle_gamma   60.003
_symmetry_Int_Tables_number   1
_cell_volume   112.720
_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
  Be  Be0  1  0.000  1.000  0.500  1.0
  Be  Be1  1  0.000  1.000  0.000  1.0
  Be  Be2  1  0.831  0.337  0.759  1.0
  Be  Be3  1  0.337  0.831  0.759  1.0
  Be  Be4  1  0.831  0.831  0.759  1.0
  Be  Be5  1  0.169  0.663  0.241  1.0
  Be  Be6  1  0.663  0.169  0.241  1.0
  Be  Be7  1  0.169  0.169  0.241  1.0
  Al  Al8  1  0.333  0.333  0.578  1.0
  Al  Al9  1  0.667  0.667  0.422  1.0
  Cr  Cr10  1  0.667  0.667  0.052  1.0
  Cr  Cr11  1  0.333  0.333  0.948  1.0
[/CIF]
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