data_TaTcSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.98
_cell_length_b   4.98
_cell_length_c   4.98
_cell_angle_alpha   131.68
_cell_angle_beta   131.68
_cell_angle_gamma   70.74
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TaTcSe2
_chemical_formula_sum   'Ta1 Tc1 Se2'
_cell_volume   67.38
_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  Ta2  1  0.04  0.0  0.03  1.0
  Tc  Tc3  1  0.0  0.0  0.06  1.0
  Se  Se0  1  0.0  0.04  0.03  1.0
  Se  Se1  1  0.0  0.0  0.0  1.0

data_TaTcSe2
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.07
_cell_length_b   4.07
_cell_length_c   4.98
_cell_angle_alpha   114.16
_cell_angle_beta   114.16
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TaTcSe2
_chemical_formula_sum   'Ta1 Tc1 Se2'
_cell_volume   67.38
_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  0.97  0.0  0.01  1.0
  Tc  Tc1  1  0.94  0.0  0.94  1.0
  Se  Se2  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.01  0.04  0.01  1.0

Ta Tc Se Se
Ta Tc Se Se 0 3 o o o 0 1 o o o 1 2 o o o 1 3 o o o 2 3 o o o 
TaTcSe2 is alpha Niobium phosphide-derived structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one TaTcSe2 cluster. Ta(1) is bonded in a single-bond geometry to one Tc(1), one Se(1), and one Se(2) atom. The Ta(1)-Tc(1) bond length is 0.30 Å. The Ta(1)-Se(1) bond length is 0.21 Å. The Ta(1)-Se(2) bond length is 0.14 Å. Tc(1) is bonded in a 3-coordinate geometry to one Ta(1), one Se(1), and one Se(2) atom. The Tc(1)-Se(1) bond length is 0.30 Å. The Tc(1)-Se(2) bond length is 0.29 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to one Ta(1), one Tc(1), and one Se(2) atom. The Se(1)-Se(2) bond length is 0.14 Å. In the second Se site, Se(2) is bonded in a distorted single-bond geometry to one Ta(1), one Tc(1), and one Se(1) atom.