The structure described by Si crystallizes in the orthorhombic Cmce space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 11-coordinate geometry to five equivalent Si(1) and six equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to four equivalent Si(2) and six equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.078
_cell_length_b   5.078
_cell_length_c   5.183
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   118.997
_symmetry_Int_Tables_number   1
_cell_volume   116.893
_cell_formula_units_Z   8
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  0.344  0.344  0.826  1.0
  Si  Si1  1  0.656  0.656  0.174  1.0
  Si  Si2  1  0.156  0.156  0.326  1.0
  Si  Si3  1  0.844  0.844  0.674  1.0
  Si  Si4  1  0.706  0.294  0.500  1.0
  Si  Si5  1  0.206  0.794  0.000  1.0
  Si  Si6  1  0.294  0.706  0.500  1.0
  Si  Si7  1  0.794  0.206  0.000  1.0
[/CIF]
.
The structure described by Si crystallizes in the orthorhombic Cmce space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 11-coordinate geometry to five equivalent Si(1) and six equivalent Si(2) atoms. In the second Si site, Si(2) is bonded in a 10-coordinate geometry to four equivalent Si(2) and six equivalent Si(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.078
_cell_length_b   5.078
_cell_length_c   5.183
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   118.997
_symmetry_Int_Tables_number   1
_cell_volume   116.893
_cell_formula_units_Z   8
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  0.344  0.344  0.826  1.0
  Si  Si1  1  0.656  0.656  0.174  1.0
  Si  Si2  1  0.156  0.156  0.326  1.0
  Si  Si3  1  0.844  0.844  0.674  1.0
  Si  Si4  1  0.706  0.294  0.500  1.0
  Si  Si5  1  0.206  0.794  0.000  1.0
  Si  Si6  1  0.294  0.706  0.500  1.0
  Si  Si7  1  0.794  0.206  0.000  1.0
[/CIF]
.