The material described by Sr11(SiN5)2 crystallizes in the tetragonal P4_2/mnm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent N(4) and four equivalent N(1) atoms to form SrN6 octahedra that share edges with two equivalent Sr(1)N6 octahedra and edges with eight equivalent Sr(2)N5 trigonal bipyramids. In the second Sr site, Sr(2) is bonded to one N(1), two equivalent N(2), and two equivalent N(4) atoms to form distorted SrN5 trigonal bipyramids that share corners with three equivalent Sr(2)N5 trigonal bipyramids, edges with two equivalent Sr(1)N6 octahedra, and edges with three equivalent Sr(2)N5 trigonal bipyramids. In the third Sr site, Sr(3) is bonded in a distorted square co-planar geometry to two equivalent N(1) and two equivalent N(3) atoms. In the fourth Sr site, Sr(4) is bonded in a 4-coordinate geometry to one N(3) and three equivalent N(2) atoms. Si(1) is bonded in a linear geometry to one N(3) and one N(4) atom. There are four inequivalent N sites. In the first N site, N(3) is bonded to two equivalent Sr(3), two equivalent Sr(4), and one Si(1) atom to form distorted NSr4Si trigonal bipyramids that share  a cornercorner with one N(4)Sr5Si octahedra, corners with two equivalent N(1)Sr6 octahedra, corners with two equivalent N(3)Sr4Si trigonal bipyramids, and  an edgeedge with one N(1)Sr6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second N site, N(4) is bonded to one Sr(1), four equivalent Sr(2), and one Si(1) atom to form distorted NSr5Si octahedra that share  a cornercorner with one N(4)Sr5Si octahedra,  a cornercorner with one N(3)Sr4Si trigonal bipyramid, edges with two equivalent N(4)Sr5Si octahedra, and edges with four equivalent N(1)Sr6 octahedra. The corner-sharing octahedra are not tilted. In the third N site, N(1) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Sr(3) atoms to form NSr6 octahedra that share corners with two equivalent N(1)Sr6 octahedra, corners with two equivalent N(3)Sr4Si trigonal bipyramids, edges with three equivalent N(1)Sr6 octahedra, edges with four equivalent N(4)Sr5Si octahedra, and  an edgeedge with one N(3)Sr4Si trigonal bipyramid. The corner-sharing octahedra are not tilted. In the fourth N site, N(2) is bonded in a 5-coordinate geometry to two equivalent Sr(2) and three equivalent Sr(4) atoms. is represented by the CIF file [CIF]
data_Sr11(SiN5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.031
_cell_length_b   16.031
_cell_length_c   3.877
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   996.429
_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  0.500  0.500  0.500  1.0
  Sr  Sr1  1  0.000  0.000  0.000  1.0
  Sr  Sr2  1  0.980  0.797  0.500  1.0
  Sr  Sr3  1  0.020  0.203  0.500  1.0
  Sr  Sr4  1  0.520  0.297  0.000  1.0
  Sr  Sr5  1  0.480  0.703  0.000  1.0
  Sr  Sr6  1  0.797  0.980  0.500  1.0
  Sr  Sr7  1  0.203  0.020  0.500  1.0
  Sr  Sr8  1  0.297  0.520  0.000  1.0
  Sr  Sr9  1  0.703  0.480  0.000  1.0
  Sr  Sr10  1  0.665  0.665  0.500  1.0
  Sr  Sr11  1  0.335  0.335  0.500  1.0
  Sr  Sr12  1  0.835  0.165  0.000  1.0
  Sr  Sr13  1  0.165  0.835  0.000  1.0
  Sr  Sr14  1  0.378  0.897  0.500  1.0
  Sr  Sr15  1  0.622  0.103  0.500  1.0
  Sr  Sr16  1  0.122  0.397  0.000  1.0
  Sr  Sr17  1  0.878  0.603  0.000  1.0
  Sr  Sr18  1  0.897  0.378  0.500  1.0
  Sr  Sr19  1  0.103  0.622  0.500  1.0
  Sr  Sr20  1  0.397  0.122  0.000  1.0
  Sr  Sr21  1  0.603  0.878  0.000  1.0
  Si  Si22  1  0.311  0.689  0.500  1.0
  Si  Si23  1  0.689  0.311  0.500  1.0
  Si  Si24  1  0.189  0.189  0.000  1.0
  Si  Si25  1  0.811  0.811  0.000  1.0
  N  N26  1  0.088  0.912  0.500  1.0
  N  N27  1  0.912  0.088  0.500  1.0
  N  N28  1  0.412  0.412  0.000  1.0
  N  N29  1  0.588  0.588  0.000  1.0
  N  N30  1  0.480  0.188  0.500  1.0
  N  N31  1  0.520  0.812  0.500  1.0
  N  N32  1  0.020  0.688  0.000  1.0
  N  N33  1  0.980  0.312  0.000  1.0
  N  N34  1  0.188  0.480  0.500  1.0
  N  N35  1  0.812  0.520  0.500  1.0
  N  N36  1  0.688  0.020  0.000  1.0
  N  N37  1  0.312  0.980  0.000  1.0
  N  N38  1  0.240  0.760  0.500  1.0
  N  N39  1  0.760  0.240  0.500  1.0
  N  N40  1  0.260  0.260  0.000  1.0
  N  N41  1  0.740  0.740  0.000  1.0
  N  N42  1  0.383  0.617  0.500  1.0
  N  N43  1  0.617  0.383  0.500  1.0
  N  N44  1  0.117  0.117  0.000  1.0
  N  N45  1  0.883  0.883  0.000  1.0
[/CIF]
.
The material described by Sr11(SiN5)2 crystallizes in the tetragonal P4_2/mnm space group. There are four inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to two equivalent N(4) and four equivalent N(1) atoms to form SrN6 octahedra that share edges with two equivalent Sr(1)N6 octahedra and edges with eight equivalent Sr(2)N5 trigonal bipyramids. In the second Sr site, Sr(2) is bonded to one N(1), two equivalent N(2), and two equivalent N(4) atoms to form distorted SrN5 trigonal bipyramids that share corners with three equivalent Sr(2)N5 trigonal bipyramids, edges with two equivalent Sr(1)N6 octahedra, and edges with three equivalent Sr(2)N5 trigonal bipyramids. In the third Sr site, Sr(3) is bonded in a distorted square co-planar geometry to two equivalent N(1) and two equivalent N(3) atoms. In the fourth Sr site, Sr(4) is bonded in a 4-coordinate geometry to one N(3) and three equivalent N(2) atoms. Si(1) is bonded in a linear geometry to one N(3) and one N(4) atom. There are four inequivalent N sites. In the first N site, N(3) is bonded to two equivalent Sr(3), two equivalent Sr(4), and one Si(1) atom to form distorted NSr4Si trigonal bipyramids that share  a cornercorner with one N(4)Sr5Si octahedra, corners with two equivalent N(1)Sr6 octahedra, corners with two equivalent N(3)Sr4Si trigonal bipyramids, and  an edgeedge with one N(1)Sr6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second N site, N(4) is bonded to one Sr(1), four equivalent Sr(2), and one Si(1) atom to form distorted NSr5Si octahedra that share  a cornercorner with one N(4)Sr5Si octahedra,  a cornercorner with one N(3)Sr4Si trigonal bipyramid, edges with two equivalent N(4)Sr5Si octahedra, and edges with four equivalent N(1)Sr6 octahedra. The corner-sharing octahedra are not tilted. In the third N site, N(1) is bonded to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Sr(3) atoms to form NSr6 octahedra that share corners with two equivalent N(1)Sr6 octahedra, corners with two equivalent N(3)Sr4Si trigonal bipyramids, edges with three equivalent N(1)Sr6 octahedra, edges with four equivalent N(4)Sr5Si octahedra, and  an edgeedge with one N(3)Sr4Si trigonal bipyramid. The corner-sharing octahedra are not tilted. In the fourth N site, N(2) is bonded in a 5-coordinate geometry to two equivalent Sr(2) and three equivalent Sr(4) atoms. is represented by the CIF file [CIF]
data_Sr11(SiN5)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.031
_cell_length_b   16.031
_cell_length_c   3.877
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   996.429
_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  0.500  0.500  0.500  1.0
  Sr  Sr1  1  0.000  0.000  0.000  1.0
  Sr  Sr2  1  0.980  0.797  0.500  1.0
  Sr  Sr3  1  0.020  0.203  0.500  1.0
  Sr  Sr4  1  0.520  0.297  0.000  1.0
  Sr  Sr5  1  0.480  0.703  0.000  1.0
  Sr  Sr6  1  0.797  0.980  0.500  1.0
  Sr  Sr7  1  0.203  0.020  0.500  1.0
  Sr  Sr8  1  0.297  0.520  0.000  1.0
  Sr  Sr9  1  0.703  0.480  0.000  1.0
  Sr  Sr10  1  0.665  0.665  0.500  1.0
  Sr  Sr11  1  0.335  0.335  0.500  1.0
  Sr  Sr12  1  0.835  0.165  0.000  1.0
  Sr  Sr13  1  0.165  0.835  0.000  1.0
  Sr  Sr14  1  0.378  0.897  0.500  1.0
  Sr  Sr15  1  0.622  0.103  0.500  1.0
  Sr  Sr16  1  0.122  0.397  0.000  1.0
  Sr  Sr17  1  0.878  0.603  0.000  1.0
  Sr  Sr18  1  0.897  0.378  0.500  1.0
  Sr  Sr19  1  0.103  0.622  0.500  1.0
  Sr  Sr20  1  0.397  0.122  0.000  1.0
  Sr  Sr21  1  0.603  0.878  0.000  1.0
  Si  Si22  1  0.311  0.689  0.500  1.0
  Si  Si23  1  0.689  0.311  0.500  1.0
  Si  Si24  1  0.189  0.189  0.000  1.0
  Si  Si25  1  0.811  0.811  0.000  1.0
  N  N26  1  0.088  0.912  0.500  1.0
  N  N27  1  0.912  0.088  0.500  1.0
  N  N28  1  0.412  0.412  0.000  1.0
  N  N29  1  0.588  0.588  0.000  1.0
  N  N30  1  0.480  0.188  0.500  1.0
  N  N31  1  0.520  0.812  0.500  1.0
  N  N32  1  0.020  0.688  0.000  1.0
  N  N33  1  0.980  0.312  0.000  1.0
  N  N34  1  0.188  0.480  0.500  1.0
  N  N35  1  0.812  0.520  0.500  1.0
  N  N36  1  0.688  0.020  0.000  1.0
  N  N37  1  0.312  0.980  0.000  1.0
  N  N38  1  0.240  0.760  0.500  1.0
  N  N39  1  0.760  0.240  0.500  1.0
  N  N40  1  0.260  0.260  0.000  1.0
  N  N41  1  0.740  0.740  0.000  1.0
  N  N42  1  0.383  0.617  0.500  1.0
  N  N43  1  0.617  0.383  0.500  1.0
  N  N44  1  0.117  0.117  0.000  1.0
  N  N45  1  0.883  0.883  0.000  1.0
[/CIF]
.