The material described by Ta3Si6N11 crystallizes in the tetragonal P4bm space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 6-coordinate geometry to one N(3), one N(4), two equivalent N(1), and two equivalent N(2) atoms. In the second Ta site, Ta(2) is bonded in a 8-coordinate geometry to 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(2), one N(3), and two equivalent N(1) atoms to form corner-sharing SiN4 tetrahedra. In the second Si site, Si(2) is bonded in a rectangular see-saw-like geometry to one N(3), one N(4), and two equivalent N(2) atoms. There are four inequivalent N sites. In the first N site, N(3) is bonded to one Ta(1), one Si(2), and two equivalent Si(1) atoms to form a mixture of distorted corner and edge-sharing NTaSi3 trigonal pyramids. In the second N site, N(4) is bonded in a rectangular see-saw-like geometry to two equivalent Ta(1) and two equivalent Si(2) atoms. In the third N site, N(1) is bonded to one Ta(1), one Ta(2), and two equivalent Si(1) atoms to form distorted NTa2Si2 trigonal pyramids that share  a cornercorner with one N(3)TaSi3 trigonal pyramid, corners with two equivalent N(1)Ta2Si2 trigonal pyramids,  an edgeedge with one N(3)TaSi3 trigonal pyramid, and edges with two equivalent N(1)Ta2Si2 trigonal pyramids. In the fourth N site, N(2) is bonded in a 4-coordinate geometry to one Ta(1), one Ta(2), one Si(1), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ta3Si6N11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.699
_cell_length_b   9.699
_cell_length_c   4.816
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   453.068
_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
  Ta  Ta0  1  0.326  0.826  0.946  1.0
  Ta  Ta1  1  0.674  0.174  0.946  1.0
  Ta  Ta2  1  0.174  0.326  0.946  1.0
  Ta  Ta3  1  0.826  0.674  0.946  1.0
  Ta  Ta4  1  0.500  0.500  0.004  1.0
  Ta  Ta5  1  0.000  0.000  0.004  1.0
  Si  Si6  1  0.404  0.314  0.528  1.0
  Si  Si7  1  0.596  0.686  0.528  1.0
  Si  Si8  1  0.096  0.814  0.528  1.0
  Si  Si9  1  0.904  0.186  0.528  1.0
  Si  Si10  1  0.314  0.596  0.528  1.0
  Si  Si11  1  0.686  0.404  0.528  1.0
  Si  Si12  1  0.814  0.904  0.528  1.0
  Si  Si13  1  0.186  0.096  0.528  1.0
  Si  Si14  1  0.872  0.372  0.028  1.0
  Si  Si15  1  0.128  0.628  0.028  1.0
  Si  Si16  1  0.628  0.872  0.028  1.0
  Si  Si17  1  0.372  0.128  0.028  1.0
  N  N18  1  0.313  0.441  0.700  1.0
  N  N19  1  0.687  0.559  0.700  1.0
  N  N20  1  0.187  0.941  0.700  1.0
  N  N21  1  0.813  0.059  0.700  1.0
  N  N22  1  0.441  0.687  0.700  1.0
  N  N23  1  0.559  0.313  0.700  1.0
  N  N24  1  0.941  0.813  0.700  1.0
  N  N25  1  0.059  0.187  0.700  1.0
  N  N26  1  0.392  0.300  0.173  1.0
  N  N27  1  0.608  0.700  0.173  1.0
  N  N28  1  0.108  0.800  0.173  1.0
  N  N29  1  0.892  0.200  0.173  1.0
  N  N30  1  0.300  0.608  0.173  1.0
  N  N31  1  0.700  0.392  0.173  1.0
  N  N32  1  0.800  0.892  0.173  1.0
  N  N33  1  0.200  0.108  0.173  1.0
  N  N34  1  0.823  0.323  0.694  1.0
  N  N35  1  0.177  0.677  0.694  1.0
  N  N36  1  0.677  0.823  0.694  1.0
  N  N37  1  0.323  0.177  0.694  1.0
  N  N38  1  0.500  0.000  0.026  1.0
  N  N39  1  0.000  0.500  0.026  1.0
[/CIF]
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The material described by Ta3Si6N11 crystallizes in the tetragonal P4bm space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 6-coordinate geometry to one N(3), one N(4), two equivalent N(1), and two equivalent N(2) atoms. In the second Ta site, Ta(2) is bonded in a 8-coordinate geometry to 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(2), one N(3), and two equivalent N(1) atoms to form corner-sharing SiN4 tetrahedra. In the second Si site, Si(2) is bonded in a rectangular see-saw-like geometry to one N(3), one N(4), and two equivalent N(2) atoms. There are four inequivalent N sites. In the first N site, N(3) is bonded to one Ta(1), one Si(2), and two equivalent Si(1) atoms to form a mixture of distorted corner and edge-sharing NTaSi3 trigonal pyramids. In the second N site, N(4) is bonded in a rectangular see-saw-like geometry to two equivalent Ta(1) and two equivalent Si(2) atoms. In the third N site, N(1) is bonded to one Ta(1), one Ta(2), and two equivalent Si(1) atoms to form distorted NTa2Si2 trigonal pyramids that share  a cornercorner with one N(3)TaSi3 trigonal pyramid, corners with two equivalent N(1)Ta2Si2 trigonal pyramids,  an edgeedge with one N(3)TaSi3 trigonal pyramid, and edges with two equivalent N(1)Ta2Si2 trigonal pyramids. In the fourth N site, N(2) is bonded in a 4-coordinate geometry to one Ta(1), one Ta(2), one Si(1), and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ta3Si6N11
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.699
_cell_length_b   9.699
_cell_length_c   4.816
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   453.068
_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
  Ta  Ta0  1  0.326  0.826  0.946  1.0
  Ta  Ta1  1  0.674  0.174  0.946  1.0
  Ta  Ta2  1  0.174  0.326  0.946  1.0
  Ta  Ta3  1  0.826  0.674  0.946  1.0
  Ta  Ta4  1  0.500  0.500  0.004  1.0
  Ta  Ta5  1  0.000  0.000  0.004  1.0
  Si  Si6  1  0.404  0.314  0.528  1.0
  Si  Si7  1  0.596  0.686  0.528  1.0
  Si  Si8  1  0.096  0.814  0.528  1.0
  Si  Si9  1  0.904  0.186  0.528  1.0
  Si  Si10  1  0.314  0.596  0.528  1.0
  Si  Si11  1  0.686  0.404  0.528  1.0
  Si  Si12  1  0.814  0.904  0.528  1.0
  Si  Si13  1  0.186  0.096  0.528  1.0
  Si  Si14  1  0.872  0.372  0.028  1.0
  Si  Si15  1  0.128  0.628  0.028  1.0
  Si  Si16  1  0.628  0.872  0.028  1.0
  Si  Si17  1  0.372  0.128  0.028  1.0
  N  N18  1  0.313  0.441  0.700  1.0
  N  N19  1  0.687  0.559  0.700  1.0
  N  N20  1  0.187  0.941  0.700  1.0
  N  N21  1  0.813  0.059  0.700  1.0
  N  N22  1  0.441  0.687  0.700  1.0
  N  N23  1  0.559  0.313  0.700  1.0
  N  N24  1  0.941  0.813  0.700  1.0
  N  N25  1  0.059  0.187  0.700  1.0
  N  N26  1  0.392  0.300  0.173  1.0
  N  N27  1  0.608  0.700  0.173  1.0
  N  N28  1  0.108  0.800  0.173  1.0
  N  N29  1  0.892  0.200  0.173  1.0
  N  N30  1  0.300  0.608  0.173  1.0
  N  N31  1  0.700  0.392  0.173  1.0
  N  N32  1  0.800  0.892  0.173  1.0
  N  N33  1  0.200  0.108  0.173  1.0
  N  N34  1  0.823  0.323  0.694  1.0
  N  N35  1  0.177  0.677  0.694  1.0
  N  N36  1  0.677  0.823  0.694  1.0
  N  N37  1  0.323  0.177  0.694  1.0
  N  N38  1  0.500  0.000  0.026  1.0
  N  N39  1  0.000  0.500  0.026  1.0
[/CIF]
.