data_ZnSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.43
_cell_length_b   6.43
_cell_length_c   6.43
_cell_angle_alpha   26.34
_cell_angle_beta   26.34
_cell_angle_gamma   26.34
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ZnSi2
_chemical_formula_sum   'Zn1 Si2'
_cell_volume   46.18
_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
  Zn  Zn2  1  0.0  0.0  0.0  1.0
  Si  Si0  1  0.0  0.0  0.54  1.0
  Si  Si1  1  0.0  0.0  0.07  1.0

data_ZnSi2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.08
_cell_length_b   2.93
_cell_length_c   6.43
_cell_angle_alpha   90.0
_cell_angle_beta   105.25
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   ZnSi2
_chemical_formula_sum   'Zn2 Si4'
_cell_volume   92.35
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Zn  Zn0  2  0.0  0.0  0.0  1.0
  Si  Si1  2  0.0  0.0  0.93  1.0
  Si  Si2  2  0.0  0.0  0.46  1.0

Zn Si Si
ZnSi2 crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two ZnSi2 clusters. Zn(1) is bonded in a single-bond geometry to one Si(1) and one Si(2) atom. The Zn(1)-Si(1) bond length is 2.94 Å. The Zn(1)-Si(2) bond length is 0.47 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a distorted single-bond geometry to one Zn(1) atom. In the second Si site, Si(2) is bonded in a single-bond geometry to one Zn(1) atom.