data_NbTc4Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.18
_cell_length_b   5.18
_cell_length_c   5.18
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbTc4Se
_chemical_formula_sum   'Nb1 Tc4 Se1'
_cell_volume   98.32
_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
  Nb  Nb0  1  0.5  0.5  0.5  1.0
  Tc  Tc2  1  0.58  0.58  0.74  1.0
  Tc  Tc3  1  0.58  0.74  0.58  1.0
  Tc  Tc4  1  0.74  0.58  0.58  1.0
  Tc  Tc5  1  0.74  0.74  0.74  1.0
  Se  Se1  1  0.0  0.0  0.0  1.0

data_NbTc4Se
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.18
_cell_length_b   5.18
_cell_length_c   12.69
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   NbTc4Se
_chemical_formula_sum   'Nb3 Tc12 Se3'
_cell_volume   294.97
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Nb  Nb0  3  0.0  0.0  0.5  1.0
  Tc  Tc1  9  0.05  0.11  0.36  1.0
  Tc  Tc2  3  0.0  0.0  0.26  1.0
  Se  Se3  3  0.0  0.0  0.0  1.0

Nb Tc Tc Tc Tc Se
NbTc4Se crystallizes in the trigonal R3m space group. Nb(1) is bonded in a 6-coordinate geometry to three equivalent Tc(1) and three equivalent Tc(2) atoms. All Nb(1)-Tc(1) bond lengths are 1.86 Å. All Nb(1)-Tc(2) bond lengths are 3.17 Å. There are two inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 2-coordinate geometry to one Nb(1), one Tc(2), two equivalent Tc(1), and two equivalent Se(1) atoms. The Tc(1)-Tc(2) bond length is 1.46 Å. Both Tc(1)-Tc(1) bond lengths are 0.85 Å. Both Tc(1)-Se(1) bond lengths are 2.81 Å. In the second Tc site, Tc(2) is bonded in a 10-coordinate geometry to three equivalent Nb(1), three equivalent Tc(1), and four equivalent Se(1) atoms. There are three shorter (3.15 Å) and one longer (3.24 Å) Tc(2)-Se(1) bond length. Se(1) is bonded in a 7-coordinate geometry to four equivalent Tc(2) and six equivalent Tc(1) atoms.