data_SiW4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.15
_cell_length_b   5.15
_cell_length_c   5.15
_cell_angle_alpha   95.59
_cell_angle_beta   95.59
_cell_angle_gamma   143.61
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiW4
_chemical_formula_sum   'Si1 W4'
_cell_volume   77.2
_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
  W  W1  1  0.75  0.39  0.0  1.0
  W  W2  1  0.39  0.17  0.0  1.0
  W  W3  1  0.71  0.08  0.61  1.0
  W  W4  1  0.08  0.29  0.61  1.0

data_SiW4
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.22
_cell_length_b   5.15
_cell_length_c   5.15
_cell_angle_alpha   84.41
_cell_angle_beta   71.81
_cell_angle_gamma   71.81
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SiW4
_chemical_formula_sum   'Si1 W4'
_cell_volume   77.2
_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
  W  W1  1  0.17  0.0  0.21  1.0
  W  W2  1  0.39  0.0  0.37  1.0
  W  W3  1  0.47  0.61  0.63  1.0
  W  W4  1  0.68  0.61  0.79  1.0

Si W W W W
Si W W W W 0 2 o o o 1 2 o o o 3 4 + o o 
(W)2W2Si crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one W cluster and one W2Si cluster. In the W cluster, there are two inequivalent W sites. In the first W site, W(3) is bonded in a distorted single-bond geometry to one W(4) atom. The W(3)-W(4) bond length is 1.20 Å. In the second W site, W(4) is bonded in a 1-coordinate geometry to one W(3) atom. In the W2Si cluster, there are two inequivalent W sites. In the first W site, W(1) is bonded in a 1-coordinate geometry to one W(2) atom. The W(1)-W(2) bond length is 1.20 Å. In the second W site, W(2) is bonded in a 2-coordinate geometry to one W(1) and one Si(1) atom. The W(2)-Si(1) bond length is 1.38 Å. Si(1) is bonded in a distorted single-bond geometry to one W(2) atom.