data_LaSi2Br
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.15
_cell_length_b   5.15
_cell_length_c   5.15
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   LaSi2Br
_chemical_formula_sum   'La1 Si2 Br1'
_cell_volume   96.79
_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
  La  La1  1  0.64  0.64  0.64  1.0
  Si  Si2  1  0.82  0.82  0.82  1.0
  Si  Si3  1  0.47  0.47  0.47  1.0
  Br  Br0  1  0.0  0.0  0.0  1.0

data_LaSi2Br
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.15
_cell_length_b   5.15
_cell_length_c   12.62
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   LaSi2Br
_chemical_formula_sum   'La3 Si6 Br3'
_cell_volume   290.37
_cell_formula_units_Z   3
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+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+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
  La  La0  3  0.0  0.0  0.36  1.0
  Si  Si1  3  0.0  0.0  0.18  1.0
  Si  Si2  3  0.0  0.0  0.53  1.0
  Br  Br3  3  0.0  0.0  0.0  1.0

La Si Si Br
LaSi2Br crystallizes in the trigonal R3m space group. La(1) is bonded to one Si(1), one Si(2), and three equivalent Br(1) atoms to form distorted LaSi2Br3 trigonal bipyramids that share corners with six equivalent La(1)Si2Br3 trigonal bipyramids and  a cornercorner with one Br(1)La3Si trigonal pyramid. The La(1)-Si(1) bond length is 2.25 Å. The La(1)-Si(2) bond length is 2.25 Å. All La(1)-Br(1) bond lengths are 2.99 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a linear geometry to one La(1) and one Br(1) atom. The Si(1)-Br(1) bond length is 2.25 Å. In the second Si site, Si(2) is bonded in a single-bond geometry to one La(1) atom. Br(1) is bonded to three equivalent La(1) and one Si(1) atom to form BrLa3Si trigonal pyramids that share  a cornercorner with one La(1)Si2Br3 trigonal bipyramid and corners with six equivalent Br(1)La3Si trigonal pyramids.