The structure described by Si3N4 crystallizes in the cubic I-43d space group. Si(1) is bonded to four equivalent N(1) atoms to form corner-sharing SiN4 tetrahedra. N(1) is bonded in a trigonal planar geometry to three equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Si3N4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.619
_cell_length_b   5.619
_cell_length_c   5.619
_cell_angle_alpha   109.471
_cell_angle_beta   109.471
_cell_angle_gamma   109.471
_symmetry_Int_Tables_number   1
_cell_volume   136.572
_cell_formula_units_Z   2
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  0.375  0.250  0.625  1.0
  Si  Si1  1  0.625  0.375  0.250  1.0
  Si  Si2  1  0.875  0.125  0.750  1.0
  Si  Si3  1  0.250  0.625  0.375  1.0
  Si  Si4  1  0.750  0.875  0.125  1.0
  Si  Si5  1  0.125  0.750  0.875  1.0
  N  N6  1  0.500  0.000  0.063  1.0
  N  N7  1  0.563  0.500  0.000  1.0
  N  N8  1  0.937  0.937  0.937  1.0
  N  N9  1  0.000  0.563  0.500  1.0
  N  N10  1  0.437  0.437  0.437  1.0
  N  N11  1  0.000  0.063  0.500  1.0
  N  N12  1  0.500  0.000  0.563  1.0
  N  N13  1  0.063  0.500  0.000  1.0
[/CIF]
.
The structure described by Si3N4 crystallizes in the cubic I-43d space group. Si(1) is bonded to four equivalent N(1) atoms to form corner-sharing SiN4 tetrahedra. N(1) is bonded in a trigonal planar geometry to three equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Si3N4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.619
_cell_length_b   5.619
_cell_length_c   5.619
_cell_angle_alpha   109.471
_cell_angle_beta   109.471
_cell_angle_gamma   109.471
_symmetry_Int_Tables_number   1
_cell_volume   136.572
_cell_formula_units_Z   2
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  0.375  0.250  0.625  1.0
  Si  Si1  1  0.625  0.375  0.250  1.0
  Si  Si2  1  0.875  0.125  0.750  1.0
  Si  Si3  1  0.250  0.625  0.375  1.0
  Si  Si4  1  0.750  0.875  0.125  1.0
  Si  Si5  1  0.125  0.750  0.875  1.0
  N  N6  1  0.500  0.000  0.063  1.0
  N  N7  1  0.563  0.500  0.000  1.0
  N  N8  1  0.937  0.937  0.937  1.0
  N  N9  1  0.000  0.563  0.500  1.0
  N  N10  1  0.437  0.437  0.437  1.0
  N  N11  1  0.000  0.063  0.500  1.0
  N  N12  1  0.500  0.000  0.563  1.0
  N  N13  1  0.063  0.500  0.000  1.0
[/CIF]
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