data_Y2TaBr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.21
_cell_length_b   5.21
_cell_length_c   5.21
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Y2TaBr
_chemical_formula_sum   'Y2 Ta1 Br1'
_cell_volume   100.18
_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
  Y  Y2  1  0.69  0.69  0.69  1.0
  Y  Y3  1  0.53  0.53  0.53  1.0
  Ta  Ta1  1  0.84  0.84  0.84  1.0
  Br  Br0  1  0.0  0.0  0.0  1.0

data_Y2TaBr
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.21
_cell_length_b   5.21
_cell_length_c   12.77
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Y2TaBr
_chemical_formula_sum   'Y6 Ta3 Br3'
_cell_volume   300.53
_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
  Y  Y0  3  0.0  0.0  0.31  1.0
  Y  Y1  3  0.0  0.0  0.47  1.0
  Ta  Ta2  3  0.0  0.0  0.16  1.0
  Br  Br3  3  0.0  0.0  0.0  1.0

Y Y Ta Br
Y Y Ta Br 0 1 o o o 0 2 o o o 2 3 + + + 
Y2TaBr crystallizes in the trigonal R3m space group. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one Y(2), one Ta(1), and three equivalent Br(1) atoms to form distorted YYTaBr3 trigonal bipyramids that share corners with six equivalent Y(1)YTaBr3 trigonal bipyramids,  a cornercorner with one Br(1)Y3Ta trigonal pyramid, and corners with three equivalent Y(2)YTa3 trigonal pyramids. The Y(1)-Y(2) bond length is 2.00 Å. The Y(1)-Ta(1) bond length is 2.00 Å. All Y(1)-Br(1) bond lengths are 3.02 Å. In the second Y site, Y(2) is bonded to one Y(1) and three equivalent Ta(1) atoms to form YYTa3 trigonal pyramids that share corners with three equivalent Y(1)YTaBr3 trigonal bipyramids, corners with six equivalent Y(2)YTa3 trigonal pyramids, and edges with three equivalent Br(1)Y3Ta trigonal pyramids. All Y(2)-Ta(1) bond lengths are 3.02 Å. Ta(1) is bonded in a distorted linear geometry to one Y(1), three equivalent Y(2), and one Br(1) atom. The Ta(1)-Br(1) bond length is 2.00 Å. Br(1) is bonded to three equivalent Y(1) and one Ta(1) atom to form distorted BrY3Ta trigonal pyramids that share  a cornercorner with one Y(1)YTaBr3 trigonal bipyramid, corners with six equivalent Br(1)Y3Ta trigonal pyramids, and edges with three equivalent Y(2)YTa3 trigonal pyramids.