The compound described by Tb4N2Se3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to one N(1), two equivalent Se(2), and three equivalent Se(1) atoms. In the second Tb site, Tb(2) is bonded in a 6-coordinate geometry to three equivalent N(1), one Se(2), and two equivalent Se(1) atoms. N(1) is bonded to one Tb(1) and three equivalent Tb(2) atoms to form NTb4 tetrahedra that share  a cornercorner with one Se(2)Tb6 octahedra, corners with seven equivalent Se(1)Tb5 square pyramids, corners with two equivalent N(1)Tb4 tetrahedra, edges with two equivalent Se(2)Tb6 octahedra,  an edgeedge with one Se(1)Tb5 square pyramid, and edges with two equivalent N(1)Tb4 tetrahedra. The corner-sharing octahedral tilt angles are 27°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Tb(2) and three equivalent Tb(1) atoms to form SeTb5 square pyramids that share corners with two equivalent Se(2)Tb6 octahedra, corners with seven equivalent N(1)Tb4 tetrahedra, edges with three equivalent Se(2)Tb6 octahedra, edges with four equivalent Se(1)Tb5 square pyramids, and  an edgeedge with one N(1)Tb4 tetrahedra. The corner-sharing octahedral tilt angles are 12°. In the second Se site, Se(2) is bonded to two equivalent Tb(2) and four equivalent Tb(1) atoms to form SeTb6 octahedra that share corners with four equivalent Se(1)Tb5 square pyramids, corners with two equivalent N(1)Tb4 tetrahedra, edges with two equivalent Se(2)Tb6 octahedra, edges with six equivalent Se(1)Tb5 square pyramids, and edges with four equivalent N(1)Tb4 tetrahedra. is represented by the CIF card [CIF]
data_Tb4Se3N2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.937
_cell_length_b   6.952
_cell_length_c   8.168
_cell_angle_alpha   85.573
_cell_angle_beta   76.053
_cell_angle_gamma   73.549
_symmetry_Int_Tables_number   1
_cell_volume   208.080
_cell_formula_units_Z   1
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
  Tb  Tb0  1  0.442  0.267  0.849  1.0
  Tb  Tb1  1  0.558  0.733  0.151  1.0
  Tb  Tb2  1  0.756  0.127  0.361  1.0
  Tb  Tb3  1  0.244  0.873  0.639  1.0
  Se  Se4  1  0.835  0.559  0.771  1.0
  Se  Se5  1  0.000  0.000  0.000  1.0
  Se  Se6  1  0.165  0.441  0.229  1.0
  N  N7  1  0.352  0.934  0.362  1.0
  N  N8  1  0.648  0.066  0.638  1.0
[/CIF]
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The compound described by Tb4N2Se3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to one N(1), two equivalent Se(2), and three equivalent Se(1) atoms. In the second Tb site, Tb(2) is bonded in a 6-coordinate geometry to three equivalent N(1), one Se(2), and two equivalent Se(1) atoms. N(1) is bonded to one Tb(1) and three equivalent Tb(2) atoms to form NTb4 tetrahedra that share  a cornercorner with one Se(2)Tb6 octahedra, corners with seven equivalent Se(1)Tb5 square pyramids, corners with two equivalent N(1)Tb4 tetrahedra, edges with two equivalent Se(2)Tb6 octahedra,  an edgeedge with one Se(1)Tb5 square pyramid, and edges with two equivalent N(1)Tb4 tetrahedra. The corner-sharing octahedral tilt angles are 27°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Tb(2) and three equivalent Tb(1) atoms to form SeTb5 square pyramids that share corners with two equivalent Se(2)Tb6 octahedra, corners with seven equivalent N(1)Tb4 tetrahedra, edges with three equivalent Se(2)Tb6 octahedra, edges with four equivalent Se(1)Tb5 square pyramids, and  an edgeedge with one N(1)Tb4 tetrahedra. The corner-sharing octahedral tilt angles are 12°. In the second Se site, Se(2) is bonded to two equivalent Tb(2) and four equivalent Tb(1) atoms to form SeTb6 octahedra that share corners with four equivalent Se(1)Tb5 square pyramids, corners with two equivalent N(1)Tb4 tetrahedra, edges with two equivalent Se(2)Tb6 octahedra, edges with six equivalent Se(1)Tb5 square pyramids, and edges with four equivalent N(1)Tb4 tetrahedra. is represented by the CIF card [CIF]
data_Tb4Se3N2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.937
_cell_length_b   6.952
_cell_length_c   8.168
_cell_angle_alpha   85.573
_cell_angle_beta   76.053
_cell_angle_gamma   73.549
_symmetry_Int_Tables_number   1
_cell_volume   208.080
_cell_formula_units_Z   1
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
  Tb  Tb0  1  0.442  0.267  0.849  1.0
  Tb  Tb1  1  0.558  0.733  0.151  1.0
  Tb  Tb2  1  0.756  0.127  0.361  1.0
  Tb  Tb3  1  0.244  0.873  0.639  1.0
  Se  Se4  1  0.835  0.559  0.771  1.0
  Se  Se5  1  0.000  0.000  0.000  1.0
  Se  Se6  1  0.165  0.441  0.229  1.0
  N  N7  1  0.352  0.934  0.362  1.0
  N  N8  1  0.648  0.066  0.638  1.0
[/CIF]
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