data_TaAlSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.39
_cell_length_b   3.4
_cell_length_c   5.35
_cell_angle_alpha   90.0
_cell_angle_beta   91.17
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TaAlSi2
_chemical_formula_sum   'Ta1 Al1 Si2'
_cell_volume   61.66
_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  0.95  0.0  0.68  1.0
  Al  Al0  1  0.0  0.0  0.0  1.0
  Si  Si1  1  0.66  0.7  0.35  1.0
  Si  Si2  1  0.62  0.7  1.0  1.0

data_TaAlSi2
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.39
_cell_length_b   3.4
_cell_length_c   5.35
_cell_angle_alpha   90.0
_cell_angle_beta   91.17
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TaAlSi2
_chemical_formula_sum   'Ta1 Al1 Si2'
_cell_volume   61.66
_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  Ta0  1  0.95  0.0  0.68  1.0
  Al  Al1  1  0.0  0.0  0.0  1.0
  Si  Si2  1  0.62  0.7  1.0  1.0
  Si  Si3  1  0.66  0.7  0.35  1.0

Ta Al Si Si
Ta Al Si Si 0 1 + o + 0 2 o - o 1 3 - - - 2 3 o o - 
TaAlSi2 crystallizes in the triclinic P1 space group. Ta(1) is bonded in a 2-coordinate geometry to one Al(1) and three equivalent Si(1) atoms. The Ta(1)-Al(1) bond length is 1.74 Å. There are a spread of Ta(1)-Si(1) bond distances ranging from 2.21-3.16 Å. Al(1) is bonded in a 5-coordinate geometry to one Ta(1), one Si(1), and three equivalent Si(2) atoms. The Al(1)-Si(1) bond length is 2.46 Å. There are a spread of Al(1)-Si(2) bond distances ranging from 1.64-2.70 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 5-coordinate geometry to three equivalent Ta(1), one Al(1), and one Si(2) atom. The Si(1)-Si(2) bond length is 1.91 Å. In the second Si site, Si(2) is bonded in a 1-coordinate geometry to three equivalent Al(1) and one Si(1) atom.