The compound described by CsTaSe3 crystallizes in the orthorhombic Pnma space group. Cs(1) is bonded to four equivalent Se(2) and eight equivalent Se(1) atoms to form CsSe12 cuboctahedra that share corners with six equivalent Cs(1)Se12 cuboctahedra, corners with six equivalent Ta(1)Se6 octahedra, faces with eight equivalent Cs(1)Se12 cuboctahedra, and faces with six equivalent Ta(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 2-24°. Ta(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form distorted TaSe6 octahedra that share corners with six equivalent Cs(1)Se12 cuboctahedra, faces with six equivalent Cs(1)Se12 cuboctahedra, and faces with two equivalent Ta(1)Se6 octahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to four equivalent Cs(1) and two equivalent Ta(1) atoms. In the second Se site, Se(2) is bonded in a 2-coordinate geometry to four equivalent Cs(1) and two equivalent Ta(1) atoms. is represented by the CIF file [CIF]
data_CsTaSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.207
_cell_length_b   7.690
_cell_length_c   13.333
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   636.378
_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
  Cs  Cs0  1  0.752  0.250  0.910  1.0
  Cs  Cs1  1  0.248  0.750  0.090  1.0
  Cs  Cs2  1  0.748  0.750  0.410  1.0
  Cs  Cs3  1  0.252  0.250  0.590  1.0
  Ta  Ta4  1  0.466  0.750  0.772  1.0
  Ta  Ta5  1  0.034  0.250  0.272  1.0
  Ta  Ta6  1  0.534  0.250  0.228  1.0
  Ta  Ta7  1  0.966  0.750  0.728  1.0
  Se  Se8  1  0.245  0.985  0.834  1.0
  Se  Se9  1  0.231  0.250  0.100  1.0
  Se  Se10  1  0.255  0.485  0.334  1.0
  Se  Se11  1  0.755  0.485  0.166  1.0
  Se  Se12  1  0.245  0.515  0.834  1.0
  Se  Se13  1  0.269  0.750  0.600  1.0
  Se  Se14  1  0.769  0.750  0.900  1.0
  Se  Se15  1  0.745  0.985  0.666  1.0
  Se  Se16  1  0.255  0.015  0.334  1.0
  Se  Se17  1  0.755  0.015  0.166  1.0
  Se  Se18  1  0.731  0.250  0.400  1.0
  Se  Se19  1  0.745  0.515  0.666  1.0
[/CIF]
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The compound described by CsTaSe3 crystallizes in the orthorhombic Pnma space group. Cs(1) is bonded to four equivalent Se(2) and eight equivalent Se(1) atoms to form CsSe12 cuboctahedra that share corners with six equivalent Cs(1)Se12 cuboctahedra, corners with six equivalent Ta(1)Se6 octahedra, faces with eight equivalent Cs(1)Se12 cuboctahedra, and faces with six equivalent Ta(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 2-24°. Ta(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form distorted TaSe6 octahedra that share corners with six equivalent Cs(1)Se12 cuboctahedra, faces with six equivalent Cs(1)Se12 cuboctahedra, and faces with two equivalent Ta(1)Se6 octahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to four equivalent Cs(1) and two equivalent Ta(1) atoms. In the second Se site, Se(2) is bonded in a 2-coordinate geometry to four equivalent Cs(1) and two equivalent Ta(1) atoms. is represented by the CIF file [CIF]
data_CsTaSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.207
_cell_length_b   7.690
_cell_length_c   13.333
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   636.378
_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
  Cs  Cs0  1  0.752  0.250  0.910  1.0
  Cs  Cs1  1  0.248  0.750  0.090  1.0
  Cs  Cs2  1  0.748  0.750  0.410  1.0
  Cs  Cs3  1  0.252  0.250  0.590  1.0
  Ta  Ta4  1  0.466  0.750  0.772  1.0
  Ta  Ta5  1  0.034  0.250  0.272  1.0
  Ta  Ta6  1  0.534  0.250  0.228  1.0
  Ta  Ta7  1  0.966  0.750  0.728  1.0
  Se  Se8  1  0.245  0.985  0.834  1.0
  Se  Se9  1  0.231  0.250  0.100  1.0
  Se  Se10  1  0.255  0.485  0.334  1.0
  Se  Se11  1  0.755  0.485  0.166  1.0
  Se  Se12  1  0.245  0.515  0.834  1.0
  Se  Se13  1  0.269  0.750  0.600  1.0
  Se  Se14  1  0.769  0.750  0.900  1.0
  Se  Se15  1  0.745  0.985  0.666  1.0
  Se  Se16  1  0.255  0.015  0.334  1.0
  Se  Se17  1  0.755  0.015  0.166  1.0
  Se  Se18  1  0.731  0.250  0.400  1.0
  Se  Se19  1  0.745  0.515  0.666  1.0
[/CIF]
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