The crystal structure described by Si is BC8 structured and crystallizes in the cubic Ia-3 space group. Si(1) is bonded to four equivalent Si(1) atoms to form corner-sharing SiSi4 trigonal pyramids. is represented by the CIF card [CIF]
data_Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.764
_cell_length_b   5.764
_cell_length_c   5.764
_cell_angle_alpha   109.471
_cell_angle_beta   109.471
_cell_angle_gamma   109.471
_symmetry_Int_Tables_number   1
_cell_volume   147.415
_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  0.203  0.000  0.000  1.0
  Si  Si1  1  0.000  0.703  0.500  1.0
  Si  Si2  1  0.500  0.500  0.203  1.0
  Si  Si3  1  0.297  0.797  0.297  1.0
  Si  Si4  1  0.797  0.000  0.000  1.0
  Si  Si5  1  0.000  0.297  0.500  1.0
  Si  Si6  1  0.500  0.500  0.797  1.0
  Si  Si7  1  0.703  0.203  0.703  1.0
[/CIF]
.
The crystal structure described by Si is BC8 structured and crystallizes in the cubic Ia-3 space group. Si(1) is bonded to four equivalent Si(1) atoms to form corner-sharing SiSi4 trigonal pyramids. is represented by the CIF card [CIF]
data_Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.764
_cell_length_b   5.764
_cell_length_c   5.764
_cell_angle_alpha   109.471
_cell_angle_beta   109.471
_cell_angle_gamma   109.471
_symmetry_Int_Tables_number   1
_cell_volume   147.415
_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  0.203  0.000  0.000  1.0
  Si  Si1  1  0.000  0.703  0.500  1.0
  Si  Si2  1  0.500  0.500  0.203  1.0
  Si  Si3  1  0.297  0.797  0.297  1.0
  Si  Si4  1  0.797  0.000  0.000  1.0
  Si  Si5  1  0.000  0.297  0.500  1.0
  Si  Si6  1  0.500  0.500  0.797  1.0
  Si  Si7  1  0.703  0.203  0.703  1.0
[/CIF]
.