data_SrSi4Tc
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.25
_cell_length_b   5.25
_cell_length_c   5.25
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SrSi4Tc
_chemical_formula_sum   'Sr1 Si4 Tc1'
_cell_volume   102.43
_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
  Sr  Sr4  1  0.0  0.0  0.0  1.0
  Si  Si0  1  0.81  0.81  0.62  1.0
  Si  Si1  1  0.81  0.62  0.81  1.0
  Si  Si2  1  0.62  0.81  0.81  1.0
  Si  Si3  1  0.62  0.62  0.62  1.0
  Tc  Tc5  1  0.86  0.86  0.86  1.0

data_SrSi4Tc
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.25
_cell_length_b   5.25
_cell_length_c   12.86
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   SrSi4Tc
_chemical_formula_sum   'Sr3 Si12 Tc3'
_cell_volume   307.28
_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
  Sr  Sr0  3  0.0  0.0  0.0  1.0
  Si  Si1  9  0.13  0.06  0.25  1.0
  Tc  Tc2  3  0.0  0.0  0.14  1.0
  Si  Si3  3  0.0  0.0  0.38  1.0

Sr Si Si Si Si Tc
SrTcSi4 crystallizes in the trigonal R3m space group. Sr(1) is bonded to one Tc(1), three equivalent Si(1), and three equivalent Si(2) atoms to form distorted corner-sharing SrSi6Tc tetrahedra. The Sr(1)-Tc(1) bond length is 1.84 Å. All Sr(1)-Si(1) bond lengths are 2.66 Å. All Sr(1)-Si(2) bond lengths are 3.09 Å. Tc(1) is bonded in a single-bond geometry to one Sr(1) and three equivalent Si(1) atoms. All Tc(1)-Si(1) bond lengths are 1.55 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 5-coordinate geometry to one Sr(1), one Tc(1), one Si(2), and two equivalent Si(1) atoms. The Si(1)-Si(2) bond length is 1.72 Å. Both Si(1)-Si(1) bond lengths are 0.99 Å. In the second Si site, Si(2) is bonded in a 6-coordinate geometry to three equivalent Sr(1) and three equivalent Si(1) atoms.