The material described by Si crystallizes in the orthorhombic Fmmm space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to three equivalent Si(1) and four equivalent Si(2) atoms to form a mixture of distorted corner and edge-sharing SiSi7 trigonal bipyramids. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to four equivalent Si(1) and four equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.598
_cell_length_b   3.598
_cell_length_c   5.237
_cell_angle_alpha   108.145
_cell_angle_beta   108.145
_cell_angle_gamma   95.354
_symmetry_Int_Tables_number   1
_cell_volume   59.833
_cell_formula_units_Z   4
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  0.727  0.273  0.000  1.0
  Si  Si1  1  0.273  0.727  0.000  1.0
  Si  Si2  1  0.780  0.780  0.560  1.0
  Si  Si3  1  0.220  0.220  0.440  1.0
[/CIF]
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The material described by Si crystallizes in the orthorhombic Fmmm space group. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to three equivalent Si(1) and four equivalent Si(2) atoms to form a mixture of distorted corner and edge-sharing SiSi7 trigonal bipyramids. In the second Si site, Si(2) is bonded in a 8-coordinate geometry to four equivalent Si(1) and four equivalent Si(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.598
_cell_length_b   3.598
_cell_length_c   5.237
_cell_angle_alpha   108.145
_cell_angle_beta   108.145
_cell_angle_gamma   95.354
_symmetry_Int_Tables_number   1
_cell_volume   59.833
_cell_formula_units_Z   4
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  0.727  0.273  0.000  1.0
  Si  Si1  1  0.273  0.727  0.000  1.0
  Si  Si2  1  0.780  0.780  0.560  1.0
  Si  Si3  1  0.220  0.220  0.440  1.0
[/CIF]
.