data_CaThSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.09
_cell_length_b   5.09
_cell_length_c   5.09
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaThSi2
_chemical_formula_sum   'Ca1 Th1 Si2'
_cell_volume   93.34
_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
  Ca  Ca0  1  0.0  0.0  0.0  1.0
  Th  Th3  1  0.6  0.6  0.6  1.0
  Si  Si1  1  0.4  0.4  0.4  1.0
  Si  Si2  1  0.8  0.8  0.8  1.0

data_CaThSi2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.09
_cell_length_b   5.09
_cell_length_c   12.47
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   CaThSi2
_chemical_formula_sum   'Ca3 Th3 Si6'
_cell_volume   280.03
_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
  Ca  Ca0  3  0.0  0.0  0.0  1.0
  Th  Th1  3  0.0  0.0  0.4  1.0
  Si  Si2  3  0.0  0.0  0.2  1.0
  Si  Si3  3  0.0  0.0  0.6  1.0

Ca Th Si Si
Ca Th Si Si 0 3 - - - 0 3 - - o 0 3 o - - 0 3 - o - 0 1 - - o 0 1 - o - 0 1 o - - 0 2 - o o 0 2 o - o 0 2 o o - 1 2 o o o 1 2 o + o 1 2 + o o 1 2 o o + 1 3 o o o 2 3 - o o 2 3 o - o 2 3 o o - 
CaThSi2 crystallizes in the trigonal R3m space group. Ca(1) is bonded in a 10-coordinate geometry to three equivalent Th(1), three equivalent Si(1), and four equivalent Si(2) atoms. All Ca(1)-Th(1) bond lengths are 3.05 Å. All Ca(1)-Si(1) bond lengths are 3.06 Å. There is one shorter (2.49 Å) and three longer (3.38 Å) Ca(1)-Si(2) bond lengths. Th(1) is bonded in a distorted linear geometry to three equivalent Ca(1), one Si(1), and one Si(2) atom. The Th(1)-Si(1) bond length is 2.49 Å. The Th(1)-Si(2) bond length is 2.49 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 4-coordinate geometry to three equivalent Ca(1) and one Th(1) atom. In the second Si site, Si(2) is bonded in a linear geometry to four equivalent Ca(1) and one Th(1) atom.