The compound described by Sr3Ta3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 5-coordinate geometry to one N(3), one N(4), one N(5), and two equivalent N(2) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one N(2), one N(3), one N(4), two equivalent N(1), and two equivalent N(5) atoms. In the third Sr site, Sr(3) is bonded in a 5-coordinate geometry to one N(1), one N(2), one N(4), and two equivalent N(3) atoms. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one N(1), one N(5), and two equivalent N(3) atoms to form a mixture of corner and edge-sharing TaN4 tetrahedra. In the second Ta site, Ta(2) is bonded to one N(1), one N(2), and two equivalent N(4) atoms to form a mixture of distorted corner and edge-sharing TaN4 trigonal pyramids. In the third Ta site, Ta(3) is bonded to one N(1), one N(2), one N(4), and one N(5) atom to form a mixture of distorted corner and edge-sharing TaN4 tetrahedra. There are five inequivalent N sites. In the first N site, N(1) is bonded to one Sr(3), two equivalent Sr(2), one Ta(1), one Ta(2), and one Ta(3) atom to form distorted NSr3Ta3 octahedra that share corners with two equivalent N(2)Sr4Ta2 octahedra,  an edgeedge with one N(1)Sr3Ta3 octahedra, and  a faceface with one N(2)Sr4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 63-64°. In the second N site, N(2) is bonded to one Sr(2), one Sr(3), two equivalent Sr(1), one Ta(2), and one Ta(3) atom to form distorted NSr4Ta2 octahedra that share corners with two equivalent N(1)Sr3Ta3 octahedra,  an edgeedge with one N(2)Sr4Ta2 octahedra, and  a faceface with one N(1)Sr3Ta3 octahedra. The corner-sharing octahedral tilt angles range from 63-64°. In the third N site, N(3) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), two equivalent Sr(3), and two equivalent Ta(1) atoms. In the fourth N site, N(4) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Ta(3), and two equivalent Ta(2) atoms. In the fifth N site, N(5) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(3) atom. is represented by the CIF card [CIF]
data_Sr3Ta3N5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.236
_cell_length_b   8.249
_cell_length_c   8.355
_cell_angle_alpha   109.213
_cell_angle_beta   102.400
_cell_angle_gamma   102.839
_symmetry_Int_Tables_number   1
_cell_volume   375.858
_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  0.736  0.437  0.592  1.0
  Sr  Sr1  1  0.264  0.563  0.408  1.0
  Sr  Sr2  1  0.643  0.849  0.879  1.0
  Sr  Sr3  1  0.357  0.151  0.121  1.0
  Sr  Sr4  1  0.679  0.684  0.232  1.0
  Sr  Sr5  1  0.321  0.316  0.768  1.0
  Ta  Ta6  1  0.901  0.307  0.961  1.0
  Ta  Ta7  1  0.099  0.693  0.039  1.0
  Ta  Ta8  1  0.729  0.019  0.598  1.0
  Ta  Ta9  1  0.271  0.981  0.402  1.0
  Ta  Ta10  1  0.091  0.874  0.685  1.0
  Ta  Ta11  1  0.909  0.126  0.315  1.0
  N  N12  1  0.018  0.092  0.838  1.0
  N  N13  1  0.982  0.908  0.162  1.0
  N  N14  1  0.731  0.748  0.572  1.0
  N  N15  1  0.269  0.252  0.428  1.0
  N  N16  1  0.778  0.516  0.933  1.0
  N  N17  1  0.222  0.484  0.067  1.0
  N  N18  1  0.403  0.954  0.639  1.0
  N  N19  1  0.597  0.046  0.361  1.0
  N  N20  1  0.200  0.753  0.848  1.0
  N  N21  1  0.800  0.247  0.152  1.0
[/CIF]
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The compound described by Sr3Ta3N5 crystallizes in the triclinic P-1 space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 5-coordinate geometry to one N(3), one N(4), one N(5), and two equivalent N(2) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to one N(2), one N(3), one N(4), two equivalent N(1), and two equivalent N(5) atoms. In the third Sr site, Sr(3) is bonded in a 5-coordinate geometry to one N(1), one N(2), one N(4), and two equivalent N(3) atoms. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one N(1), one N(5), and two equivalent N(3) atoms to form a mixture of corner and edge-sharing TaN4 tetrahedra. In the second Ta site, Ta(2) is bonded to one N(1), one N(2), and two equivalent N(4) atoms to form a mixture of distorted corner and edge-sharing TaN4 trigonal pyramids. In the third Ta site, Ta(3) is bonded to one N(1), one N(2), one N(4), and one N(5) atom to form a mixture of distorted corner and edge-sharing TaN4 tetrahedra. There are five inequivalent N sites. In the first N site, N(1) is bonded to one Sr(3), two equivalent Sr(2), one Ta(1), one Ta(2), and one Ta(3) atom to form distorted NSr3Ta3 octahedra that share corners with two equivalent N(2)Sr4Ta2 octahedra,  an edgeedge with one N(1)Sr3Ta3 octahedra, and  a faceface with one N(2)Sr4Ta2 octahedra. The corner-sharing octahedral tilt angles range from 63-64°. In the second N site, N(2) is bonded to one Sr(2), one Sr(3), two equivalent Sr(1), one Ta(2), and one Ta(3) atom to form distorted NSr4Ta2 octahedra that share corners with two equivalent N(1)Sr3Ta3 octahedra,  an edgeedge with one N(2)Sr4Ta2 octahedra, and  a faceface with one N(1)Sr3Ta3 octahedra. The corner-sharing octahedral tilt angles range from 63-64°. In the third N site, N(3) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), two equivalent Sr(3), and two equivalent Ta(1) atoms. In the fourth N site, N(4) is bonded in a 6-coordinate geometry to one Sr(1), one Sr(2), one Sr(3), one Ta(3), and two equivalent Ta(2) atoms. In the fifth N site, N(5) is bonded in a 5-coordinate geometry to one Sr(1), two equivalent Sr(2), one Ta(1), and one Ta(3) atom. is represented by the CIF card [CIF]
data_Sr3Ta3N5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.236
_cell_length_b   8.249
_cell_length_c   8.355
_cell_angle_alpha   109.213
_cell_angle_beta   102.400
_cell_angle_gamma   102.839
_symmetry_Int_Tables_number   1
_cell_volume   375.858
_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  0.736  0.437  0.592  1.0
  Sr  Sr1  1  0.264  0.563  0.408  1.0
  Sr  Sr2  1  0.643  0.849  0.879  1.0
  Sr  Sr3  1  0.357  0.151  0.121  1.0
  Sr  Sr4  1  0.679  0.684  0.232  1.0
  Sr  Sr5  1  0.321  0.316  0.768  1.0
  Ta  Ta6  1  0.901  0.307  0.961  1.0
  Ta  Ta7  1  0.099  0.693  0.039  1.0
  Ta  Ta8  1  0.729  0.019  0.598  1.0
  Ta  Ta9  1  0.271  0.981  0.402  1.0
  Ta  Ta10  1  0.091  0.874  0.685  1.0
  Ta  Ta11  1  0.909  0.126  0.315  1.0
  N  N12  1  0.018  0.092  0.838  1.0
  N  N13  1  0.982  0.908  0.162  1.0
  N  N14  1  0.731  0.748  0.572  1.0
  N  N15  1  0.269  0.252  0.428  1.0
  N  N16  1  0.778  0.516  0.933  1.0
  N  N17  1  0.222  0.484  0.067  1.0
  N  N18  1  0.403  0.954  0.639  1.0
  N  N19  1  0.597  0.046  0.361  1.0
  N  N20  1  0.200  0.753  0.848  1.0
  N  N21  1  0.800  0.247  0.152  1.0
[/CIF]
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