data_Tl2CoSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.47
_cell_length_b   5.47
_cell_length_c   5.47
_cell_angle_alpha   130.94
_cell_angle_beta   130.94
_cell_angle_gamma   71.91
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Tl2CoSe
_chemical_formula_sum   'Tl2 Co1 Se1'
_cell_volume   91.56
_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
  Tl  Tl2  1  0.0  0.0  0.43  1.0
  Tl  Tl3  1  0.0  0.27  0.22  1.0
  Co  Co0  1  0.0  0.0  0.0  1.0
  Se  Se1  1  0.27  0.0  0.22  1.0

data_Tl2CoSe
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.55
_cell_length_b   4.55
_cell_length_c   5.47
_cell_angle_alpha   114.53
_cell_angle_beta   114.53
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Tl2CoSe
_chemical_formula_sum   'Tl2 Co1 Se1'
_cell_volume   91.56
_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
  Tl  Tl0  1  0.06  0.27  0.06  1.0
  Tl  Tl1  1  0.57  0.0  0.57  1.0
  Co  Co2  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.78  0.0  0.06  1.0

Tl Tl Co Se
CoTl2Se crystallizes in the triclinic P1 space group. Co(1) is bonded in a water-like geometry to one Tl(2), two equivalent Tl(1), and one Se(1) atom. The Co(1)-Tl(2) bond length is 1.15 Å. There is one shorter (2.36 Å) and one longer (3.11 Å) Co(1)-Tl(1) bond length. The Co(1)-Se(1) bond length is 1.15 Å. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 6-coordinate geometry to two equivalent Co(1), two equivalent Tl(2), and two equivalent Se(1) atoms. There is one shorter (2.44 Å) and one longer (3.33 Å) Tl(1)-Tl(2) bond length. There is one shorter (2.44 Å) and one longer (3.33 Å) Tl(1)-Se(1) bond length. In the second Tl site, Tl(2) is bonded in a single-bond geometry to one Co(1) and two equivalent Tl(1) atoms. Se(1) is bonded in a single-bond geometry to one Co(1) and two equivalent Tl(1) atoms.