data_TaAs3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.24
_cell_length_b   5.24
_cell_length_c   5.24
_cell_angle_alpha   140.78
_cell_angle_beta   128.72
_cell_angle_gamma   66.41
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TaAs3
_chemical_formula_sum   'Ta1 As3'
_cell_volume   69.78
_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  0.38  1.0
  As  As0  1  0.76  0.0  0.01  1.0
  As  As1  1  0.0  0.0  0.0  1.0
  As  As2  1  0.0  0.27  0.37  1.0

data_TaAs3
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.51
_cell_length_b   4.53
_cell_length_c   5.24
_cell_angle_alpha   115.64
_cell_angle_beta   109.61
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TaAs3
_chemical_formula_sum   'Ta1 As3'
_cell_volume   69.78
_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  0.62  0.62  0.62  1.0
  As  As1  1  0.0  0.0  0.0  1.0
  As  As2  1  0.63  0.9  0.9  1.0
  As  As3  1  0.74  0.99  0.74  1.0

Ta As As As
Ta As As As 0 3 o o o 0 1 - o o 1 3 + o o 1 2 + o o 2 3 o o o 
TaAs3 crystallizes in the triclinic P1 space group. Ta(1) is bonded in a 2-coordinate geometry to one As(3), two equivalent As(1), and two equivalent As(2) atoms. The Ta(1)-As(3) bond length is 1.45 Å. There is one shorter (1.51 Å) and one longer (3.20 Å) Ta(1)-As(1) bond length. There is one shorter (2.00 Å) and one longer (3.24 Å) Ta(1)-As(2) bond length. There are three inequivalent As sites. In the first As site, As(1) is bonded in a 4-coordinate geometry to two equivalent Ta(1), one As(2), and one As(3) atom. The As(1)-As(2) bond length is 1.31 Å. The As(1)-As(3) bond length is 1.21 Å. In the second As site, As(2) is bonded in a 5-coordinate geometry to two equivalent Ta(1), one As(1), and two equivalent As(3) atoms. There is one shorter (1.22 Å) and one longer (2.45 Å) As(2)-As(3) bond length. In the third As site, As(3) is bonded in a 1-coordinate geometry to one Ta(1), one As(1), and two equivalent As(2) atoms.