The crystal structure described by In5(SiN3)2 crystallizes in the monoclinic C2/c space group. There are three inequivalent In sites. In the first In site, In(1) is bonded in a 4-coordinate geometry to two equivalent N(1) and two equivalent N(2) atoms. In the second In site, In(2) is bonded in a distorted single-bond geometry to one N(3) atom. In the third In site, In(3) is bonded to one N(2), two equivalent N(1), and two equivalent N(3) atoms to form distorted InN5 trigonal bipyramids that share corners with two equivalent Si(1)N4 tetrahedra, corners with two equivalent In(3)N5 trigonal bipyramids, edges with two equivalent Si(1)N4 tetrahedra, and  an edgeedge with one In(3)N5 trigonal bipyramid. Si(1) is bonded to one N(1), one N(3), and two equivalent N(2) atoms to form SiN4 tetrahedra that share corners with two equivalent In(3)N5 trigonal bipyramids,  an edgeedge with one Si(1)N4 tetrahedra, and edges with two equivalent In(3)N5 trigonal bipyramids. There are three inequivalent N sites. In the first N site, N(2) is bonded in a 4-coordinate geometry to one In(1), one In(3), and two equivalent Si(1) atoms. In the second N site, N(3) is bonded in a 4-coordinate geometry to one In(2), two equivalent In(3), and one Si(1) atom. In the third N site, N(1) is bonded in a distorted see-saw-like geometry to one In(1), two equivalent In(3), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_In5(SiN3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.889
_cell_length_b   7.373
_cell_length_c   11.622
_cell_angle_alpha   90.000
_cell_angle_beta   95.868
_cell_angle_gamma   128.756
_symmetry_Int_Tables_number   1
_cell_volume   390.077
_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
  In  In0  1  0.000  0.459  0.750  1.0
  In  In1  1  0.000  0.541  0.250  1.0
  In  In2  1  0.175  0.845  0.011  1.0
  In  In3  1  0.825  0.670  0.489  1.0
  In  In4  1  0.825  0.155  0.989  1.0
  In  In5  1  0.175  0.330  0.511  1.0
  In  In6  1  0.309  0.093  0.707  1.0
  In  In7  1  0.691  0.784  0.793  1.0
  In  In8  1  0.691  0.907  0.293  1.0
  In  In9  1  0.309  0.216  0.207  1.0
  Si  Si10  1  0.553  0.916  0.582  1.0
  Si  Si11  1  0.447  0.363  0.918  1.0
  Si  Si12  1  0.447  0.084  0.418  1.0
  Si  Si13  1  0.553  0.637  0.082  1.0
  N  N14  1  0.342  0.805  0.697  1.0
  N  N15  1  0.658  0.464  0.803  1.0
  N  N16  1  0.658  0.195  0.303  1.0
  N  N17  1  0.342  0.536  0.197  1.0
  N  N18  1  0.599  0.178  0.566  1.0
  N  N19  1  0.401  0.580  0.934  1.0
  N  N20  1  0.401  0.822  0.434  1.0
  N  N21  1  0.599  0.420  0.066  1.0
  N  N22  1  0.852  0.921  0.621  1.0
  N  N23  1  0.148  0.069  0.879  1.0
  N  N24  1  0.148  0.079  0.379  1.0
  N  N25  1  0.852  0.931  0.121  1.0
[/CIF]
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The crystal structure described by In5(SiN3)2 crystallizes in the monoclinic C2/c space group. There are three inequivalent In sites. In the first In site, In(1) is bonded in a 4-coordinate geometry to two equivalent N(1) and two equivalent N(2) atoms. In the second In site, In(2) is bonded in a distorted single-bond geometry to one N(3) atom. In the third In site, In(3) is bonded to one N(2), two equivalent N(1), and two equivalent N(3) atoms to form distorted InN5 trigonal bipyramids that share corners with two equivalent Si(1)N4 tetrahedra, corners with two equivalent In(3)N5 trigonal bipyramids, edges with two equivalent Si(1)N4 tetrahedra, and  an edgeedge with one In(3)N5 trigonal bipyramid. Si(1) is bonded to one N(1), one N(3), and two equivalent N(2) atoms to form SiN4 tetrahedra that share corners with two equivalent In(3)N5 trigonal bipyramids,  an edgeedge with one Si(1)N4 tetrahedra, and edges with two equivalent In(3)N5 trigonal bipyramids. There are three inequivalent N sites. In the first N site, N(2) is bonded in a 4-coordinate geometry to one In(1), one In(3), and two equivalent Si(1) atoms. In the second N site, N(3) is bonded in a 4-coordinate geometry to one In(2), two equivalent In(3), and one Si(1) atom. In the third N site, N(1) is bonded in a distorted see-saw-like geometry to one In(1), two equivalent In(3), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_In5(SiN3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.889
_cell_length_b   7.373
_cell_length_c   11.622
_cell_angle_alpha   90.000
_cell_angle_beta   95.868
_cell_angle_gamma   128.756
_symmetry_Int_Tables_number   1
_cell_volume   390.077
_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
  In  In0  1  0.000  0.459  0.750  1.0
  In  In1  1  0.000  0.541  0.250  1.0
  In  In2  1  0.175  0.845  0.011  1.0
  In  In3  1  0.825  0.670  0.489  1.0
  In  In4  1  0.825  0.155  0.989  1.0
  In  In5  1  0.175  0.330  0.511  1.0
  In  In6  1  0.309  0.093  0.707  1.0
  In  In7  1  0.691  0.784  0.793  1.0
  In  In8  1  0.691  0.907  0.293  1.0
  In  In9  1  0.309  0.216  0.207  1.0
  Si  Si10  1  0.553  0.916  0.582  1.0
  Si  Si11  1  0.447  0.363  0.918  1.0
  Si  Si12  1  0.447  0.084  0.418  1.0
  Si  Si13  1  0.553  0.637  0.082  1.0
  N  N14  1  0.342  0.805  0.697  1.0
  N  N15  1  0.658  0.464  0.803  1.0
  N  N16  1  0.658  0.195  0.303  1.0
  N  N17  1  0.342  0.536  0.197  1.0
  N  N18  1  0.599  0.178  0.566  1.0
  N  N19  1  0.401  0.580  0.934  1.0
  N  N20  1  0.401  0.822  0.434  1.0
  N  N21  1  0.599  0.420  0.066  1.0
  N  N22  1  0.852  0.921  0.621  1.0
  N  N23  1  0.148  0.069  0.879  1.0
  N  N24  1  0.148  0.079  0.379  1.0
  N  N25  1  0.852  0.931  0.121  1.0
[/CIF]
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