The structure described by Sr5(SiN3)2 crystallizes in the monoclinic C2/c space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to two equivalent N(1), two equivalent N(2), and two equivalent N(3) atoms. In the second Sr site, Sr(2) is bonded in a 5-coordinate geometry to one N(2), two equivalent N(1), and two equivalent N(3) atoms. In the third Sr site, Sr(3) is bonded in a 5-coordinate geometry to one N(2), two equivalent N(1), and two equivalent N(3) atoms. Si(1) is bonded to one N(1), one N(3), and two equivalent N(2) atoms to form edge-sharing SiN4 tetrahedra. There are three inequivalent N sites. In the first N site, N(2) is bonded in a 2-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), and two equivalent Si(1) atoms. In the second N site, N(3) is bonded to one Sr(1), two equivalent Sr(2), two equivalent Sr(3), and one Si(1) atom to form a mixture of distorted corner, face, and edge-sharing NSr5Si octahedra. The corner-sharing octahedral tilt angles range from 22-76°. In the third N site, N(1) is bonded to one Sr(1), two equivalent Sr(2), two equivalent Sr(3), and one Si(1) atom to form a mixture of distorted corner and edge-sharing NSr5Si octahedra. The corner-sharing octahedral tilt angles range from 22-76°. is represented by the CIF file [CIF]
data_Sr5(SiN3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.022
_cell_length_b   6.022
_cell_length_c   13.389
_cell_angle_alpha   81.355
_cell_angle_beta   81.355
_cell_angle_gamma   65.171
_symmetry_Int_Tables_number   1
_cell_volume   433.537
_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
  Sr  Sr0  1  0.614  0.386  0.750  1.0
  Sr  Sr1  1  0.386  0.614  0.250  1.0
  Sr  Sr2  1  0.205  0.676  0.995  1.0
  Sr  Sr3  1  0.324  0.795  0.505  1.0
  Sr  Sr4  1  0.795  0.324  0.005  1.0
  Sr  Sr5  1  0.676  0.205  0.495  1.0
  Sr  Sr6  1  0.921  0.768  0.714  1.0
  Sr  Sr7  1  0.232  0.079  0.786  1.0
  Sr  Sr8  1  0.079  0.232  0.286  1.0
  Sr  Sr9  1  0.768  0.921  0.214  1.0
  Si  Si10  1  0.089  0.360  0.574  1.0
  Si  Si11  1  0.640  0.911  0.926  1.0
  Si  Si12  1  0.911  0.640  0.426  1.0
  Si  Si13  1  0.360  0.089  0.074  1.0
  N  N14  1  0.292  0.403  0.644  1.0
  N  N15  1  0.597  0.708  0.856  1.0
  N  N16  1  0.708  0.597  0.356  1.0
  N  N17  1  0.403  0.292  0.144  1.0
  N  N18  1  0.806  0.638  0.558  1.0
  N  N19  1  0.362  0.194  0.942  1.0
  N  N20  1  0.194  0.362  0.442  1.0
  N  N21  1  0.638  0.806  0.058  1.0
  N  N22  1  0.014  0.117  0.625  1.0
  N  N23  1  0.883  0.986  0.875  1.0
  N  N24  1  0.986  0.883  0.375  1.0
  N  N25  1  0.117  0.014  0.125  1.0
[/CIF]
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The structure described by Sr5(SiN3)2 crystallizes in the monoclinic C2/c space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 6-coordinate geometry to two equivalent N(1), two equivalent N(2), and two equivalent N(3) atoms. In the second Sr site, Sr(2) is bonded in a 5-coordinate geometry to one N(2), two equivalent N(1), and two equivalent N(3) atoms. In the third Sr site, Sr(3) is bonded in a 5-coordinate geometry to one N(2), two equivalent N(1), and two equivalent N(3) atoms. Si(1) is bonded to one N(1), one N(3), and two equivalent N(2) atoms to form edge-sharing SiN4 tetrahedra. There are three inequivalent N sites. In the first N site, N(2) is bonded in a 2-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), and two equivalent Si(1) atoms. In the second N site, N(3) is bonded to one Sr(1), two equivalent Sr(2), two equivalent Sr(3), and one Si(1) atom to form a mixture of distorted corner, face, and edge-sharing NSr5Si octahedra. The corner-sharing octahedral tilt angles range from 22-76°. In the third N site, N(1) is bonded to one Sr(1), two equivalent Sr(2), two equivalent Sr(3), and one Si(1) atom to form a mixture of distorted corner and edge-sharing NSr5Si octahedra. The corner-sharing octahedral tilt angles range from 22-76°. is represented by the CIF file [CIF]
data_Sr5(SiN3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.022
_cell_length_b   6.022
_cell_length_c   13.389
_cell_angle_alpha   81.355
_cell_angle_beta   81.355
_cell_angle_gamma   65.171
_symmetry_Int_Tables_number   1
_cell_volume   433.537
_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
  Sr  Sr0  1  0.614  0.386  0.750  1.0
  Sr  Sr1  1  0.386  0.614  0.250  1.0
  Sr  Sr2  1  0.205  0.676  0.995  1.0
  Sr  Sr3  1  0.324  0.795  0.505  1.0
  Sr  Sr4  1  0.795  0.324  0.005  1.0
  Sr  Sr5  1  0.676  0.205  0.495  1.0
  Sr  Sr6  1  0.921  0.768  0.714  1.0
  Sr  Sr7  1  0.232  0.079  0.786  1.0
  Sr  Sr8  1  0.079  0.232  0.286  1.0
  Sr  Sr9  1  0.768  0.921  0.214  1.0
  Si  Si10  1  0.089  0.360  0.574  1.0
  Si  Si11  1  0.640  0.911  0.926  1.0
  Si  Si12  1  0.911  0.640  0.426  1.0
  Si  Si13  1  0.360  0.089  0.074  1.0
  N  N14  1  0.292  0.403  0.644  1.0
  N  N15  1  0.597  0.708  0.856  1.0
  N  N16  1  0.708  0.597  0.356  1.0
  N  N17  1  0.403  0.292  0.144  1.0
  N  N18  1  0.806  0.638  0.558  1.0
  N  N19  1  0.362  0.194  0.942  1.0
  N  N20  1  0.194  0.362  0.442  1.0
  N  N21  1  0.638  0.806  0.058  1.0
  N  N22  1  0.014  0.117  0.625  1.0
  N  N23  1  0.883  0.986  0.875  1.0
  N  N24  1  0.986  0.883  0.375  1.0
  N  N25  1  0.117  0.014  0.125  1.0
[/CIF]
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