data_CaAlSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.21
_cell_length_b   4.21
_cell_length_c   21.69
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaAlSi
_chemical_formula_sum   'Ca5 Al5 Si5'
_cell_volume   332.78
_cell_formula_units_Z   5
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  Ca5  1  1.0  0.43  0.17  1.0
  Ca  Ca6  1  1.0  0.43  0.55  1.0
  Ca  Ca7  1  1.0  0.43  0.14  1.0
  Ca  Ca8  1  1.0  0.43  0.52  1.0
  Ca  Ca9  1  1.0  0.43  0.84  1.0
  Al  Al0  1  0.0  0.0  0.53  1.0
  Al  Al1  1  0.0  0.0  0.0  1.0
  Al  Al2  1  0.0  0.0  0.16  1.0
  Al  Al3  1  0.1  0.22  0.92  1.0
  Al  Al4  1  0.1  0.22  0.77  1.0
  Si  Si10  1  0.1  0.22  0.2  1.0
  Si  Si11  1  0.1  0.22  0.0  1.0
  Si  Si12  1  0.1  0.22  0.49  1.0
  Si  Si13  1  0.0  0.0  0.55  1.0
  Si  Si14  1  0.0  0.0  0.14  1.0

data_CaAlSi
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.21
_cell_length_b   4.21
_cell_length_c   21.69
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaAlSi
_chemical_formula_sum   'Ca5 Al5 Si5'
_cell_volume   332.78
_cell_formula_units_Z   5
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  1.0  0.43  0.14  1.0
  Ca  Ca1  1  1.0  0.43  0.17  1.0
  Ca  Ca2  1  1.0  0.43  0.52  1.0
  Ca  Ca3  1  1.0  0.43  0.55  1.0
  Ca  Ca4  1  1.0  0.43  0.84  1.0
  Al  Al5  1  0.0  0.0  0.0  1.0
  Al  Al6  1  0.0  0.0  0.16  1.0
  Al  Al7  1  0.0  0.0  0.53  1.0
  Al  Al8  1  0.1  0.22  0.77  1.0
  Al  Al9  1  0.1  0.22  0.92  1.0
  Si  Si10  1  0.0  0.0  0.14  1.0
  Si  Si11  1  0.0  0.0  0.55  1.0
  Si  Si12  1  0.1  0.22  0.0  1.0
  Si  Si13  1  0.1  0.22  0.2  1.0
  Si  Si14  1  0.1  0.22  0.49  1.0

Ca Ca Ca Ca Ca Al Al Al Al Al Si Si Si Si Si
Ca Ca Ca Ca Ca Al Al Al Al Al Si Si Si Si Si 0 2 o o o 0 10 + o o 1 3 o o o 3 12 + o o 4 9 + o o 4 8 + o o 5 13 o o o 5 12 o o o 6 11 o o o 6 8 o o - 7 14 o o o 7 10 o o o 8 11 o o + 
CaAlSi crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two Ca2AlSi2 clusters and one CaAl3Si cluster. In each Ca2AlSi2 cluster, there are two inequivalent Ca sites. In the first Ca site, Ca(1,4) is bonded in a distorted bent 120 degrees geometry to one Ca(3) and one Si(1) atom. The Ca(1,4)-Ca(3) bond length is 0.52 Å. The Ca(1,4)-Si(1) bond length is 1.41 Å. In the second Ca site, Ca(3) is bonded in a 1-coordinate geometry to one Ca(1,4) atom. Al(1,3) is bonded in a distorted single-bond geometry to one Si(3) and one Si(4) atom. The Al(1,3)-Si(3) bond length is 1.24 Å. The Al(1,3)-Si(4) bond length is 0.38 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in an L-shaped geometry to one Ca(1,4) and one Al(1,3) atom. The Si(1)-Al(1,3) bond length is 1.24 Å. In the second Si site, Si(5) is bonded in a single-bond geometry to one Al(1,3) atom. The Si(5)-Al(1,3) bond length is 0.38 Å. In the CaAl3Si cluster, Ca(5) is bonded in a water-like geometry to one Al(4) and one Al(5) atom. The Ca(5)-Al(4) bond length is 2.01 Å. The Ca(5)-Al(5) bond length is 2.01 Å. There are three inequivalent Al sites. In the first Al site, Al(2) is bonded in a single-bond geometry to one Si(2) atom. The Al(2)-Si(2) bond length is 0.78 Å. In the second Al site, Al(4) is bonded in a distorted bent 150 degrees geometry to one Ca(5) and one Si(2) atom. The Al(4)-Si(2) bond length is 1.75 Å. In the third Al site, Al(5) is bonded in a single-bond geometry to one Ca(5) atom. Si(2) is bonded in a distorted single-bond geometry to one Al(2) and one Al(4) atom.