data_SiTc3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.93
_cell_length_b   2.93
_cell_length_c   6.45
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiTc3
_chemical_formula_sum   'Si1 Tc3'
_cell_volume   55.31
_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
  Si  Si0  1  0.0  0.0  0.0  1.0
  Tc  Tc1  1  0.46  0.46  0.48  1.0
  Tc  Tc2  1  0.0  0.0  0.22  1.0
  Tc  Tc3  1  0.46  0.46  0.96  1.0

data_SiTc3
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.14
_cell_length_b   4.14
_cell_length_c   6.45
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   SiTc3
_chemical_formula_sum   'Si2 Tc6'
_cell_volume   110.62
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Si  Si0  2  0.0  0.0  0.0  1.0
  Tc  Tc1  2  0.0  0.0  0.22  1.0
  Tc  Tc2  2  0.46  0.0  0.48  1.0
  Tc  Tc3  2  0.46  0.0  0.96  1.0

Si Tc Tc Tc
Tc3Si crystallizes in the monoclinic Cm space group. There are three inequivalent Tc sites. In the first Tc site, Tc(1) is bonded in a 9-coordinate geometry to one Tc(3), four equivalent Tc(1), and four equivalent Tc(2) atoms. The Tc(1)-Tc(3) bond length is 3.10 Å. All Tc(1)-Tc(1) bond lengths are 2.93 Å. There are a spread of Tc(1)-Tc(2) bond distances ranging from 2.55-2.78 Å. In the second Tc site, Tc(2) is bonded in a single-bond geometry to four equivalent Tc(1) and one Si(1) atom. The Tc(2)-Si(1) bond length is 1.45 Å. In the third Tc site, Tc(3) is bonded in a 4-coordinate geometry to one Tc(1) and four equivalent Si(1) atoms. There are a spread of Tc(3)-Si(1) bond distances ranging from 1.94-2.23 Å. Si(1) is bonded to one Tc(2) and four equivalent Tc(3) atoms to form a mixture of distorted edge and corner-sharing SiTc5 square pyramids.