data_B2Br
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.46
_cell_length_b   5.46
_cell_length_c   5.46
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   B2Br
_chemical_formula_sum   'B8 Br4'
_cell_volume   163.05
_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
  B  B0  1  0.46  0.2  1.0  1.0
  B  B1  1  1.0  0.27  0.46  1.0
  B  B2  1  0.2  1.0  0.46  1.0
  B  B3  1  0.27  0.46  1.0  1.0
  B  B4  1  1.0  0.46  0.2  1.0
  B  B5  1  0.46  1.0  0.27  1.0
  B  B6  1  0.27  0.27  0.27  1.0
  B  B7  1  0.2  0.2  0.2  1.0
  Br  Br8  1  0.73  0.0  0.73  1.0
  Br  Br9  1  0.0  0.73  0.73  1.0
  Br  Br10  1  0.0  0.0  0.0  1.0
  Br  Br11  1  0.73  0.73  0.0  1.0

data_B2Br
_symmetry_space_group_name_H-M   R3
_cell_length_a   7.73
_cell_length_b   7.73
_cell_length_c   9.46
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   146
_chemical_formula_structural   B2Br
_chemical_formula_sum   'B24 Br12'
_cell_volume   489.16
_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  'x+1/3, y+2/3, z+2/3'
  5  '-y+1/3, x-y+2/3, z+2/3'
  6  '-x+y+1/3, -x+2/3, z+2/3'
  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'
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
  B  B0  9  0.02  0.24  0.24  1.0
  B  B1  9  0.11  0.69  0.89  1.0
  B  B2  3  0.0  0.0  0.2  1.0
  B  B3  3  0.0  0.0  0.27  1.0
  Br  Br4  9  0.18  0.09  0.82  1.0
  Br  Br5  3  0.0  0.0  0.0  1.0

B B B B B B B B Br Br Br Br
B B B B B B B B Br Br Br Br 0 7 o o + 0 6 o o + 0 3 o o o 0 5 o - + 0 8 o o o 1 7 + o o 1 2 + - o 1 6 + o o 1 4 o o o 2 7 o + o 2 6 o + o 2 5 o o o 2 9 o o o 3 7 o o + 3 4 - o + 3 6 o o + 4 7 + o o 4 6 + o o 4 11 o o o 5 7 o + o 5 6 o + o 6 7 o o o 7 10 o o o 8 9 + - o 8 11 o - + 8 10 + o + 9 11 - o + 9 10 o + + 10 11 - - o 
BrB2 crystallizes in the trigonal R3 space group. There are four inequivalent B sites. In the first B site, B(1) is bonded in a 1-coordinate geometry to two equivalent B(2) and one Br(1) atom. Both B(1)-B(2) bond lengths are 1.82 Å. The B(1)-Br(1) bond length is 2.32 Å. In the second B site, B(2) is bonded in a 5-coordinate geometry to one B(3), one B(4), two equivalent B(1), and one Br(1) atom. The B(2)-B(3) bond length is 1.82 Å. The B(2)-B(4) bond length is 1.86 Å. The B(2)-Br(1) bond length is 2.52 Å. In the third B site, B(3) is bonded in a single-bond geometry to one B(4) and three equivalent B(2) atoms. The B(3)-B(4) bond length is 0.67 Å. In the fourth B site, B(4) is bonded in a distorted linear geometry to one B(3), three equivalent B(2), and one Br(2) atom. The B(4)-Br(2) bond length is 1.86 Å. There are two inequivalent Br sites. In the first Br site, Br(1) is bonded in a 5-coordinate geometry to one B(1), one B(2), one Br(2), and two equivalent Br(1) atoms. The Br(1)-Br(2) bond length is 2.07 Å. Both Br(1)-Br(1) bond lengths are 2.07 Å. In the second Br site, Br(2) is bonded in a single-bond geometry to one B(4) and three equivalent Br(1) atoms.