data_Sc3TaSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.93
_cell_length_b   4.93
_cell_length_c   4.93
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Sc3TaSi
_chemical_formula_sum   'Sc3 Ta1 Si1'
_cell_volume   119.69
_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
  Sc  Sc0  1  0.0  0.46  0.0  1.0
  Sc  Sc1  1  0.0  0.0  0.46  1.0
  Sc  Sc2  1  0.46  0.0  0.0  1.0
  Ta  Ta4  1  0.46  0.46  0.46  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

data_Sc3TaSi
_symmetry_space_group_name_H-M   R3m
_cell_length_a   6.97
_cell_length_b   6.97
_cell_length_c   8.54
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Sc3TaSi
_chemical_formula_sum   'Sc9 Ta3 Si3'
_cell_volume   359.07
_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
  Sc  Sc0  9  0.18  0.36  0.82  1.0
  Ta  Ta1  3  0.0  0.0  0.46  1.0
  Si  Si2  3  0.0  0.0  0.0  1.0

Sc Sc Sc Ta Si
Sc3TaSi is (Cubic) Perovskite structured and crystallizes in the trigonal R3m space group. Sc(1) is bonded in a distorted linear geometry to four equivalent Ta(1) and two equivalent Si(1) atoms. There are a spread of Sc(1)-Ta(1) bond distances ranging from 3.23-3.73 Å. There is one shorter (2.29 Å) and one longer (2.64 Å) Sc(1)-Si(1) bond length. Ta(1) is bonded to twelve equivalent Sc(1) atoms to form TaSc12 cuboctahedra that share corners with twelve equivalent Ta(1)Sc12 cuboctahedra, faces with six equivalent Ta(1)Sc12 cuboctahedra, and faces with eight equivalent Si(1)Sc6 octahedra. Si(1) is bonded to six equivalent Sc(1) atoms to form SiSc6 octahedra that share corners with six equivalent Si(1)Sc6 octahedra and faces with eight equivalent Ta(1)Sc12 cuboctahedra. The corner-sharing octahedra are not tilted.