The crystal structure described by Sr(Si3N4)2 crystallizes in the orthorhombic Imm2 space group. Sr(1) is bonded in a 10-coordinate geometry to two equivalent N(3), four equivalent N(1), and four equivalent N(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(3), and two equivalent N(2) atoms to form corner-sharing SiN4 tetrahedra. In the second Si site, Si(2) is bonded in a trigonal non-coplanar geometry to one N(3) and two equivalent N(2) atoms. There are three inequivalent N sites. In the first N site, N(1) is bonded in a 2-coordinate geometry to two equivalent Sr(1) and two equivalent Si(1) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Sr(1), one Si(2), and two equivalent Si(1) atoms. In the third N site, N(3) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Si(2), and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Sr(Si3N4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.812
_cell_length_b   6.547
_cell_length_c   6.547
_cell_angle_alpha   73.976
_cell_angle_beta   68.440
_cell_angle_gamma   68.440
_symmetry_Int_Tables_number   1
_cell_volume   176.038
_cell_formula_units_Z   1
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
  Sr  Sr0  1  0.343  0.500  0.500  1.0
  Si  Si1  1  0.012  0.043  0.636  1.0
  Si  Si2  1  0.691  0.364  0.957  1.0
  Si  Si3  1  0.012  0.636  0.043  1.0
  Si  Si4  1  0.691  0.957  0.364  1.0
  Si  Si5  1  0.486  0.873  0.873  1.0
  Si  Si6  1  0.232  0.127  0.127  1.0
  N  N7  1  0.786  0.291  0.709  1.0
  N  N8  1  0.404  0.984  0.620  1.0
  N  N9  1  0.888  0.817  0.817  1.0
  N  N10  1  0.008  0.016  0.380  1.0
  N  N11  1  0.786  0.709  0.291  1.0
  N  N12  1  0.404  0.620  0.984  1.0
  N  N13  1  0.008  0.380  0.016  1.0
  N  N14  1  0.522  0.183  0.183  1.0
[/CIF]
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The crystal structure described by Sr(Si3N4)2 crystallizes in the orthorhombic Imm2 space group. Sr(1) is bonded in a 10-coordinate geometry to two equivalent N(3), four equivalent N(1), and four equivalent N(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded to one N(1), one N(3), and two equivalent N(2) atoms to form corner-sharing SiN4 tetrahedra. In the second Si site, Si(2) is bonded in a trigonal non-coplanar geometry to one N(3) and two equivalent N(2) atoms. There are three inequivalent N sites. In the first N site, N(1) is bonded in a 2-coordinate geometry to two equivalent Sr(1) and two equivalent Si(1) atoms. In the second N site, N(2) is bonded in a trigonal planar geometry to one Sr(1), one Si(2), and two equivalent Si(1) atoms. In the third N site, N(3) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Si(2), and two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Sr(Si3N4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.812
_cell_length_b   6.547
_cell_length_c   6.547
_cell_angle_alpha   73.976
_cell_angle_beta   68.440
_cell_angle_gamma   68.440
_symmetry_Int_Tables_number   1
_cell_volume   176.038
_cell_formula_units_Z   1
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
  Sr  Sr0  1  0.343  0.500  0.500  1.0
  Si  Si1  1  0.012  0.043  0.636  1.0
  Si  Si2  1  0.691  0.364  0.957  1.0
  Si  Si3  1  0.012  0.636  0.043  1.0
  Si  Si4  1  0.691  0.957  0.364  1.0
  Si  Si5  1  0.486  0.873  0.873  1.0
  Si  Si6  1  0.232  0.127  0.127  1.0
  N  N7  1  0.786  0.291  0.709  1.0
  N  N8  1  0.404  0.984  0.620  1.0
  N  N9  1  0.888  0.817  0.817  1.0
  N  N10  1  0.008  0.016  0.380  1.0
  N  N11  1  0.786  0.709  0.291  1.0
  N  N12  1  0.404  0.620  0.984  1.0
  N  N13  1  0.008  0.380  0.016  1.0
  N  N14  1  0.522  0.183  0.183  1.0
[/CIF]
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