data_TaAu2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.81
_cell_length_b   9.81
_cell_length_c   9.81
_cell_angle_alpha   17.61
_cell_angle_beta   17.61
_cell_angle_gamma   17.61
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TaAu2Se
_chemical_formula_sum   'Ta1 Au2 Se1'
_cell_volume   75.5
_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
  Ta  Ta3  1  0.0  0.0  0.49  1.0
  Au  Au0  1  0.0  0.0  0.11  1.0
  Au  Au1  1  0.0  0.0  0.87  1.0
  Se  Se2  1  0.0  0.0  0.0  1.0

data_TaAu2Se
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.2
_cell_length_b   3.0
_cell_length_c   9.81
_cell_angle_alpha   90.0
_cell_angle_beta   100.18
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   TaAu2Se
_chemical_formula_sum   'Ta2 Au4 Se2'
_cell_volume   151.0
_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
  Ta  Ta0  2  0.0  0.0  0.51  1.0
  Au  Au1  2  0.0  0.0  0.89  1.0
  Au  Au2  2  0.0  0.0  0.13  1.0
  Se  Se3  2  0.0  0.0  0.0  1.0

Ta Au Au Se
Ta Au Au Se 0 0 o + - 0 0 + - o 0 0 + o - 1 3 o o o 2 3 o o + 
TaAu2Se crystallizes in the monoclinic Cm space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to six Ta(1,1); one Au(1); and one Au(2) atom to form a mixture of edge and corner-sharing TaTa6Au2 hexagonal bipyramids. All Ta(1)-Ta(1,1) bond lengths are 3.00 Å. The Ta(1)-Au(1) bond length is 3.72 Å. The Ta(1)-Au(2) bond length is 3.72 Å. In the second Ta site, Ta(1) is bonded to six Ta(1,1); one Au(1); and one Au(2) atom to form a mixture of edge and corner-sharing TaTa6Au2 hexagonal bipyramids. Both Ta(1)-Ta(1) bond lengths are 3.00 Å. The Ta(1)-Au(1) bond length is 3.72 Å. The Ta(1)-Au(2) bond length is 3.72 Å. There are two inequivalent Au sites. In the first Au site, Au(1) is bonded in a single-bond geometry to one Ta(1) and one Se(1) atom. The Au(1)-Se(1) bond length is 1.09 Å. In the second Au site, Au(2) is bonded in a single-bond geometry to one Ta(1) and one Se(1) atom. The Au(2)-Se(1) bond length is 1.29 Å. Se(1) is bonded in a linear geometry to one Au(1) and one Au(2) atom.