data_Be4Cr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.3
_cell_length_b   6.3
_cell_length_c   6.3
_cell_angle_alpha   109.47
_cell_angle_beta   109.47
_cell_angle_gamma   109.47
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Be4Cr
_chemical_formula_sum   'Be16 Cr4'
_cell_volume   192.76
_cell_formula_units_Z   4
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  0.29  0.29  0.29  1.0
  Be  Be1  1  0.65  0.35  0.35  1.0
  Be  Be2  1  0.35  0.65  0.35  1.0
  Be  Be3  1  0.35  0.35  0.65  1.0
  Be  Be4  1  0.0  0.0  0.66  1.0
  Be  Be5  1  0.0  0.0  0.62  1.0
  Be  Be6  1  0.0  0.66  0.0  1.0
  Be  Be7  1  0.0  0.62  0.0  1.0
  Be  Be8  1  0.66  0.0  0.0  1.0
  Be  Be9  1  0.62  0.0  0.0  1.0
  Be  Be10  1  0.64  0.0  0.82  1.0
  Be  Be11  1  0.0  0.64  0.82  1.0
  Be  Be12  1  0.0  0.82  0.64  1.0
  Be  Be13  1  0.64  0.82  0.0  1.0
  Be  Be14  1  0.82  0.64  0.0  1.0
  Be  Be15  1  0.82  0.0  0.64  1.0
  Cr  Cr16  1  0.95  0.95  0.95  1.0
  Cr  Cr17  1  0.31  0.69  0.69  1.0
  Cr  Cr18  1  0.69  0.31  0.69  1.0
  Cr  Cr19  1  0.69  0.69  0.31  1.0

data_Be4Cr
_symmetry_space_group_name_H-M   R3m
_cell_length_a   10.29
_cell_length_b   10.29
_cell_length_c   6.3
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Be4Cr
_chemical_formula_sum   'Be48 Cr12'
_cell_volume   578.28
_cell_formula_units_Z   12
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+2/3, y+1/3, z+1/3'
  8  '-y+2/3, x-y+1/3, z+1/3'
  9  '-x+y+2/3, -x+1/3, z+1/3'
  10  '-y+2/3, -x+1/3, z+1/3'
  11  '-x+y+2/3, y+1/3, z+1/3'
  12  'x+2/3, x-y+1/3, z+1/3'
  13  'x+1/3, y+2/3, z+2/3'
  14  '-y+1/3, x-y+2/3, z+2/3'
  15  '-x+y+1/3, -x+2/3, z+2/3'
  16  '-y+1/3, -x+2/3, z+2/3'
  17  '-x+y+1/3, y+2/3, z+2/3'
  18  'x+1/3, x-y+2/3, z+2/3'
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  18  0.0  0.18  0.82  1.0
  Be  Be1  9  0.08  0.54  0.54  1.0
  Be  Be2  9  0.11  0.55  0.55  1.0
  Be  Be3  9  0.2  0.1  0.45  1.0
  Be  Be4  3  0.0  0.0  0.29  1.0
  Cr  Cr5  9  0.08  0.54  0.23  1.0
  Cr  Cr6  3  0.0  0.0  0.95  1.0

Be Be Be Be Be Be Be Be Be Be Be Be Be Be Be Be Cr Cr Cr Cr
Be Be Be Be Be Be Be Be Be Be Be Be Be Be Be Be Cr Cr Cr Cr 0 16 - - - 0 2 o o o 0 1 o o o 0 3 o o o 1 19 o o o 1 9 o o o 1 8 o o o 1 18 o o o 1 12 + o o 1 11 + o o 2 7 o o o 2 6 o o o 2 17 o o o 2 19 o o o 2 15 o + o 2 10 o + o 3 5 o o o 3 4 o o o 3 17 o o o 3 18 o o o 3 14 o o + 3 13 o o + 4 5 o o o 4 12 o - o 4 15 - o o 4 16 - - o 4 19 - - o 5 12 o - o 5 15 - o o 5 16 - - o 5 19 - - o 6 7 o o o 6 11 o o - 6 14 - o o 6 16 - o - 6 18 - o - 7 11 o o - 7 14 - o o 7 16 - o - 7 18 - o - 8 9 o o o 8 10 o o - 8 13 o - o 8 16 o - - 8 17 o - - 9 10 o o - 9 13 o - o 9 16 o - - 9 17 o - - 10 16 o - o 10 17 o - o 10 18 o o o 11 16 - o o 11 17 o o o 11 18 - o o 12 16 - o o 12 17 o o o 12 19 - o o 13 16 o o - 13 17 o o - 13 19 o o o 14 16 o o - 14 18 o o - 14 19 o o o 15 16 o - o 15 18 o o o 15 19 o - o 
Be4Cr crystallizes in the trigonal R3m space group. There are five inequivalent Be sites. In the first Be site, Be(1) is bonded in a distorted tetrahedral geometry to three equivalent Be(2) and one Cr(1) atom. All Be(1)-Be(2) bond lengths are 2.06 Å. The Be(1)-Cr(1) bond length is 2.17 Å. In the second Be site, Be(2) is bonded in a 4-coordinate geometry to one Be(1), one Be(4), and two equivalent Cr(2) atoms. The Be(2)-Be(4) bond length is 2.43 Å. Both Be(2)-Cr(2) bond lengths are 2.21 Å. In the third Be site, Be(3) is bonded in a single-bond geometry to one Be(4), two equivalent Be(5), and one Cr(1) atom. The Be(3)-Be(4) bond length is 0.24 Å. Both Be(3)-Be(5) bond lengths are 1.10 Å. The Be(3)-Cr(1) bond length is 2.07 Å. In the fourth Be site, Be(4) is bonded in a single-bond geometry to one Be(2), one Be(3), and one Cr(2) atom. The Be(4)-Cr(2) bond length is 1.95 Å. In the fifth Be site, Be(5) is bonded in a 1-coordinate geometry to one Be(3), one Cr(1), and two equivalent Cr(2) atoms. The Be(5)-Cr(1) bond length is 2.02 Å. There is one shorter (1.98 Å) and one longer (2.29 Å) Be(5)-Cr(2) bond length. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a 10-coordinate geometry to one Be(1), three equivalent Be(3), and six equivalent Be(5) atoms. In the second Cr site, Cr(2) is bonded in a 7-coordinate geometry to one Be(4), two equivalent Be(2), and four equivalent Be(5) atoms.