The compound described by Sr2NbN3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one N(1), one N(2), two equivalent N(3), and two equivalent N(4) atoms to form distorted SrN6 pentagonal pyramids that share corners with two equivalent Sr(1)N6 pentagonal pyramids, corners with two equivalent Nb(1)N4 tetrahedra, edges with two equivalent Sr(1)N6 pentagonal pyramids, and edges with three equivalent Nb(1)N4 tetrahedra. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one N(1), one N(2), two equivalent N(3), and two equivalent N(4) atoms. Nb(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form NbN4 tetrahedra that share corners with two equivalent Sr(1)N6 pentagonal pyramids, corners with two equivalent Nb(1)N4 tetrahedra, and edges with three equivalent Sr(1)N6 pentagonal pyramids. There are four inequivalent N sites. In the first N site, N(4) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Nb(1) atom. In the second N site, N(1) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Nb(1) atoms. In the third N site, N(2) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Nb(1) atoms. In the fourth N site, N(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Nb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2NbN3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.393
_cell_length_b   6.393
_cell_length_c   12.611
_cell_angle_alpha   88.732
_cell_angle_beta   88.732
_cell_angle_gamma   123.466
_symmetry_Int_Tables_number   1
_cell_volume   429.528
_cell_formula_units_Z   4
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  0.613  0.844  0.577  1.0
  Sr  Sr1  1  0.058  0.462  0.358  1.0
  Sr  Sr2  1  0.462  0.058  0.858  1.0
  Sr  Sr3  1  0.942  0.538  0.642  1.0
  Sr  Sr4  1  0.387  0.156  0.423  1.0
  Sr  Sr5  1  0.844  0.613  0.077  1.0
  Sr  Sr6  1  0.156  0.387  0.923  1.0
  Sr  Sr7  1  0.538  0.942  0.142  1.0
  Nb  Nb8  1  0.231  0.234  0.163  1.0
  Nb  Nb9  1  0.766  0.769  0.337  1.0
  Nb  Nb10  1  0.769  0.766  0.837  1.0
  Nb  Nb11  1  0.234  0.231  0.663  1.0
  N  N12  1  0.495  0.505  0.250  1.0
  N  N13  1  0.505  0.495  0.750  1.0
  N  N14  1  0.090  0.910  0.250  1.0
  N  N15  1  0.910  0.090  0.750  1.0
  N  N16  1  0.675  1.000  0.376  1.0
  N  N17  1  0.000  0.325  0.124  1.0
  N  N18  1  0.325  0.000  0.624  1.0
  N  N19  1  1.000  0.675  0.876  1.0
  N  N20  1  0.386  0.199  0.040  1.0
  N  N21  1  0.199  0.386  0.540  1.0
  N  N22  1  0.614  0.801  0.960  1.0
  N  N23  1  0.801  0.614  0.460  1.0
[/CIF]
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The compound described by Sr2NbN3 crystallizes in the monoclinic C2/c space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one N(1), one N(2), two equivalent N(3), and two equivalent N(4) atoms to form distorted SrN6 pentagonal pyramids that share corners with two equivalent Sr(1)N6 pentagonal pyramids, corners with two equivalent Nb(1)N4 tetrahedra, edges with two equivalent Sr(1)N6 pentagonal pyramids, and edges with three equivalent Nb(1)N4 tetrahedra. In the second Sr site, Sr(2) is bonded in a 6-coordinate geometry to one N(1), one N(2), two equivalent N(3), and two equivalent N(4) atoms. Nb(1) is bonded to one N(1), one N(2), one N(3), and one N(4) atom to form NbN4 tetrahedra that share corners with two equivalent Sr(1)N6 pentagonal pyramids, corners with two equivalent Nb(1)N4 tetrahedra, and edges with three equivalent Sr(1)N6 pentagonal pyramids. There are four inequivalent N sites. In the first N site, N(4) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Nb(1) atom. In the second N site, N(1) is bonded in a distorted linear geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Nb(1) atoms. In the third N site, N(2) is bonded in a 6-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and two equivalent Nb(1) atoms. In the fourth N site, N(3) is bonded in a 5-coordinate geometry to two equivalent Sr(1), two equivalent Sr(2), and one Nb(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2NbN3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.393
_cell_length_b   6.393
_cell_length_c   12.611
_cell_angle_alpha   88.732
_cell_angle_beta   88.732
_cell_angle_gamma   123.466
_symmetry_Int_Tables_number   1
_cell_volume   429.528
_cell_formula_units_Z   4
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  0.613  0.844  0.577  1.0
  Sr  Sr1  1  0.058  0.462  0.358  1.0
  Sr  Sr2  1  0.462  0.058  0.858  1.0
  Sr  Sr3  1  0.942  0.538  0.642  1.0
  Sr  Sr4  1  0.387  0.156  0.423  1.0
  Sr  Sr5  1  0.844  0.613  0.077  1.0
  Sr  Sr6  1  0.156  0.387  0.923  1.0
  Sr  Sr7  1  0.538  0.942  0.142  1.0
  Nb  Nb8  1  0.231  0.234  0.163  1.0
  Nb  Nb9  1  0.766  0.769  0.337  1.0
  Nb  Nb10  1  0.769  0.766  0.837  1.0
  Nb  Nb11  1  0.234  0.231  0.663  1.0
  N  N12  1  0.495  0.505  0.250  1.0
  N  N13  1  0.505  0.495  0.750  1.0
  N  N14  1  0.090  0.910  0.250  1.0
  N  N15  1  0.910  0.090  0.750  1.0
  N  N16  1  0.675  1.000  0.376  1.0
  N  N17  1  0.000  0.325  0.124  1.0
  N  N18  1  0.325  0.000  0.624  1.0
  N  N19  1  1.000  0.675  0.876  1.0
  N  N20  1  0.386  0.199  0.040  1.0
  N  N21  1  0.199  0.386  0.540  1.0
  N  N22  1  0.614  0.801  0.960  1.0
  N  N23  1  0.801  0.614  0.460  1.0
[/CIF]
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