The compound described by Si is Clathrate-like structured and crystallizes in the hexagonal P6/mmm space group. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded to one Si(3), one Si(4), and two equivalent Si(2) atoms to form corner-sharing SiSi4 tetrahedra. In the second Si site, Si(5) is bonded to two equivalent Si(2) and two equivalent Si(5) atoms to form corner-sharing SiSi4 tetrahedra. In the third Si site, Si(2) is bonded to one Si(2), one Si(5), and two equivalent Si(1) atoms to form corner-sharing SiSi4 tetrahedra. In the fourth Si site, Si(3) is bonded to two equivalent Si(1) and two equivalent Si(3) atoms to form corner-sharing SiSi4 tetrahedra. In the fifth Si site, Si(4) is bonded to one Si(4) and three equivalent Si(1) atoms to form corner-sharing SiSi4 tetrahedra. is represented by the CIF card [CIF]
data_Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.171
_cell_length_b   10.171
_cell_length_c   10.346
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.996
_symmetry_Int_Tables_number   1
_cell_volume   926.993
_cell_formula_units_Z   40
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  0.291  0.081  0.688  1.0
  Si  Si1  1  0.709  0.919  0.688  1.0
  Si  Si2  1  0.919  0.709  0.312  1.0
  Si  Si3  1  0.081  0.291  0.312  1.0
  Si  Si4  1  0.709  0.919  0.312  1.0
  Si  Si5  1  0.291  0.081  0.312  1.0
  Si  Si6  1  0.081  0.291  0.688  1.0
  Si  Si7  1  0.919  0.709  0.688  1.0
  Si  Si8  1  0.119  0.500  0.813  1.0
  Si  Si9  1  0.881  0.500  0.813  1.0
  Si  Si10  1  0.500  0.881  0.187  1.0
  Si  Si11  1  0.500  0.119  0.187  1.0
  Si  Si12  1  0.881  0.500  0.187  1.0
  Si  Si13  1  0.119  0.500  0.187  1.0
  Si  Si14  1  0.500  0.119  0.813  1.0
  Si  Si15  1  0.500  0.881  0.813  1.0
  Si  Si16  1  0.119  0.119  0.813  1.0
  Si  Si17  1  0.881  0.881  0.813  1.0
  Si  Si18  1  0.881  0.881  0.187  1.0
  Si  Si19  1  0.119  0.119  0.187  1.0
  Si  Si20  1  0.368  0.632  0.500  1.0
  Si  Si21  1  0.632  0.368  0.500  1.0
  Si  Si22  1  0.291  0.709  0.688  1.0
  Si  Si23  1  0.709  0.291  0.688  1.0
  Si  Si24  1  0.291  0.709  0.312  1.0
  Si  Si25  1  0.709  0.291  0.312  1.0
  Si  Si26  1  0.167  0.833  0.612  1.0
  Si  Si27  1  0.833  0.167  0.612  1.0
  Si  Si28  1  0.167  0.833  0.388  1.0
  Si  Si29  1  0.833  0.167  0.388  1.0
  Si  Si30  1  0.367  0.235  0.500  1.0
  Si  Si31  1  0.633  0.765  0.500  1.0
  Si  Si32  1  0.765  0.633  0.500  1.0
  Si  Si33  1  0.235  0.367  0.500  1.0
  Si  Si34  1  0.258  0.258  0.000  1.0
  Si  Si35  1  0.742  0.742  0.000  1.0
  Si  Si36  1  0.258  0.500  0.000  1.0
  Si  Si37  1  0.742  0.500  0.000  1.0
  Si  Si38  1  0.500  0.742  0.000  1.0
  Si  Si39  1  0.500  0.258  0.000  1.0
[/CIF]
.
The compound described by Si is Clathrate-like structured and crystallizes in the hexagonal P6/mmm space group. There are five inequivalent Si sites. In the first Si site, Si(1) is bonded to one Si(3), one Si(4), and two equivalent Si(2) atoms to form corner-sharing SiSi4 tetrahedra. In the second Si site, Si(5) is bonded to two equivalent Si(2) and two equivalent Si(5) atoms to form corner-sharing SiSi4 tetrahedra. In the third Si site, Si(2) is bonded to one Si(2), one Si(5), and two equivalent Si(1) atoms to form corner-sharing SiSi4 tetrahedra. In the fourth Si site, Si(3) is bonded to two equivalent Si(1) and two equivalent Si(3) atoms to form corner-sharing SiSi4 tetrahedra. In the fifth Si site, Si(4) is bonded to one Si(4) and three equivalent Si(1) atoms to form corner-sharing SiSi4 tetrahedra. is represented by the CIF card [CIF]
data_Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.171
_cell_length_b   10.171
_cell_length_c   10.346
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   119.996
_symmetry_Int_Tables_number   1
_cell_volume   926.993
_cell_formula_units_Z   40
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  0.291  0.081  0.688  1.0
  Si  Si1  1  0.709  0.919  0.688  1.0
  Si  Si2  1  0.919  0.709  0.312  1.0
  Si  Si3  1  0.081  0.291  0.312  1.0
  Si  Si4  1  0.709  0.919  0.312  1.0
  Si  Si5  1  0.291  0.081  0.312  1.0
  Si  Si6  1  0.081  0.291  0.688  1.0
  Si  Si7  1  0.919  0.709  0.688  1.0
  Si  Si8  1  0.119  0.500  0.813  1.0
  Si  Si9  1  0.881  0.500  0.813  1.0
  Si  Si10  1  0.500  0.881  0.187  1.0
  Si  Si11  1  0.500  0.119  0.187  1.0
  Si  Si12  1  0.881  0.500  0.187  1.0
  Si  Si13  1  0.119  0.500  0.187  1.0
  Si  Si14  1  0.500  0.119  0.813  1.0
  Si  Si15  1  0.500  0.881  0.813  1.0
  Si  Si16  1  0.119  0.119  0.813  1.0
  Si  Si17  1  0.881  0.881  0.813  1.0
  Si  Si18  1  0.881  0.881  0.187  1.0
  Si  Si19  1  0.119  0.119  0.187  1.0
  Si  Si20  1  0.368  0.632  0.500  1.0
  Si  Si21  1  0.632  0.368  0.500  1.0
  Si  Si22  1  0.291  0.709  0.688  1.0
  Si  Si23  1  0.709  0.291  0.688  1.0
  Si  Si24  1  0.291  0.709  0.312  1.0
  Si  Si25  1  0.709  0.291  0.312  1.0
  Si  Si26  1  0.167  0.833  0.612  1.0
  Si  Si27  1  0.833  0.167  0.612  1.0
  Si  Si28  1  0.167  0.833  0.388  1.0
  Si  Si29  1  0.833  0.167  0.388  1.0
  Si  Si30  1  0.367  0.235  0.500  1.0
  Si  Si31  1  0.633  0.765  0.500  1.0
  Si  Si32  1  0.765  0.633  0.500  1.0
  Si  Si33  1  0.235  0.367  0.500  1.0
  Si  Si34  1  0.258  0.258  0.000  1.0
  Si  Si35  1  0.742  0.742  0.000  1.0
  Si  Si36  1  0.258  0.500  0.000  1.0
  Si  Si37  1  0.742  0.500  0.000  1.0
  Si  Si38  1  0.500  0.742  0.000  1.0
  Si  Si39  1  0.500  0.258  0.000  1.0
[/CIF]
.