The crystal structure described by Ta2Se3 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one Se(3), two equivalent Se(2), and three equivalent Se(1) atoms to form distorted edge-sharing TaSe6 octahedra. In the second Ta site, Ta(2) is bonded in a 6-coordinate geometry to three equivalent Se(2) and three equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted T-shaped geometry to three equivalent Ta(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Ta(1) and three equivalent Ta(2) atoms. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to one Ta(1) and three equivalent Ta(2) atoms. is represented by the CIF card [CIF]
data_Ta2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.426
_cell_length_b   6.624
_cell_length_c   9.276
_cell_angle_alpha   104.453
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   203.815
_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  0.250  0.113  0.633  1.0
  Ta  Ta1  1  0.750  0.887  0.367  1.0
  Ta  Ta2  1  0.250  0.325  0.001  1.0
  Ta  Ta3  1  0.750  0.675  0.999  1.0
  Se  Se4  1  0.250  0.728  0.512  1.0
  Se  Se5  1  0.750  0.272  0.488  1.0
  Se  Se6  1  0.250  0.967  0.158  1.0
  Se  Se7  1  0.750  0.033  0.842  1.0
  Se  Se8  1  0.750  0.476  0.205  1.0
  Se  Se9  1  0.250  0.524  0.795  1.0
[/CIF]
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The crystal structure described by Ta2Se3 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one Se(3), two equivalent Se(2), and three equivalent Se(1) atoms to form distorted edge-sharing TaSe6 octahedra. In the second Ta site, Ta(2) is bonded in a 6-coordinate geometry to three equivalent Se(2) and three equivalent Se(3) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a distorted T-shaped geometry to three equivalent Ta(1) atoms. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to two equivalent Ta(1) and three equivalent Ta(2) atoms. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to one Ta(1) and three equivalent Ta(2) atoms. is represented by the CIF card [CIF]
data_Ta2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.426
_cell_length_b   6.624
_cell_length_c   9.276
_cell_angle_alpha   104.453
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   203.815
_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  0.250  0.113  0.633  1.0
  Ta  Ta1  1  0.750  0.887  0.367  1.0
  Ta  Ta2  1  0.250  0.325  0.001  1.0
  Ta  Ta3  1  0.750  0.675  0.999  1.0
  Se  Se4  1  0.250  0.728  0.512  1.0
  Se  Se5  1  0.750  0.272  0.488  1.0
  Se  Se6  1  0.250  0.967  0.158  1.0
  Se  Se7  1  0.750  0.033  0.842  1.0
  Se  Se8  1  0.750  0.476  0.205  1.0
  Se  Se9  1  0.250  0.524  0.795  1.0
[/CIF]
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