data_KBe2Br
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.4
_cell_length_b   3.4
_cell_length_c   7.46
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   KBe2Br
_chemical_formula_sum   'K1 Be2 Br1'
_cell_volume   86.21
_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
  K  K3  1  0.0  0.0  0.53  1.0
  Be  Be0  1  0.7  0.7  0.16  1.0
  Be  Be1  1  0.0  0.0  0.05  1.0
  Br  Br2  1  0.7  0.7  0.46  1.0

data_KBe2Br
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.81
_cell_length_b   4.81
_cell_length_c   7.46
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   KBe2Br
_chemical_formula_sum   'K2 Be4 Br2'
_cell_volume   172.41
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  K  K0  2  0.0  0.0  0.53  1.0
  Be  Be1  2  0.0  0.0  0.05  1.0
  Be  Be2  2  0.2  0.5  0.16  1.0
  Br  Br3  2  0.2  0.5  0.46  1.0

K Be Be Br
KBe2Br crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two KBe2Br clusters. K(1) is bonded in a distorted single-bond geometry to one Br(1) atom. The K(1)-Br(1) bond length is 1.52 Å. There are two inequivalent Be sites. In the first Be site, Be(1) is bonded in a distorted bent 120 degrees geometry to one Be(2) and one Br(1) atom. The Be(1)-Be(2) bond length is 1.66 Å. The Be(1)-Br(1) bond length is 2.28 Å. In the second Be site, Be(2) is bonded in a single-bond geometry to one Be(1) atom. Br(1) is bonded in a 1-coordinate geometry to one K(1) and one Be(1) atom.