The structure described by TaIn(CuSe2)2 is beta beryllia-derived structured and crystallizes in the tetragonal P-42c space group. Ta(1) is bonded to four equivalent Se(1) atoms to form TaSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent In(1)Se4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Ta(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent In(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to four equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with four equivalent Ta(1)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with four equivalent In(1)Se4 tetrahedra. In(1) is bonded to four equivalent Se(1) atoms to form InSe4 tetrahedra that share corners with four equivalent Ta(1)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with four equivalent Cu(2)Se4 tetrahedra. Se(1) is bonded to one Ta(1), one Cu(1), one Cu(2), and one In(1) atom to form corner-sharing SeTaInCu2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TaIn(CuSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.819
_cell_length_b   5.819
_cell_length_c   12.217
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   413.674
_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  0.000  0.000  0.000  1.0
  Ta  Ta1  1  0.000  0.000  0.500  1.0
  In  In2  1  0.500  0.000  0.250  1.0
  In  In3  1  0.000  0.500  0.750  1.0
  Cu  Cu4  1  0.000  0.500  0.250  1.0
  Cu  Cu5  1  0.500  0.000  0.750  1.0
  Cu  Cu6  1  0.500  0.500  0.000  1.0
  Cu  Cu7  1  0.500  0.500  0.500  1.0
  Se  Se8  1  0.212  0.281  0.111  1.0
  Se  Se9  1  0.788  0.719  0.111  1.0
  Se  Se10  1  0.281  0.788  0.889  1.0
  Se  Se11  1  0.788  0.281  0.389  1.0
  Se  Se12  1  0.719  0.212  0.889  1.0
  Se  Se13  1  0.212  0.719  0.389  1.0
  Se  Se14  1  0.719  0.788  0.611  1.0
  Se  Se15  1  0.281  0.212  0.611  1.0
[/CIF]
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The structure described by TaIn(CuSe2)2 is beta beryllia-derived structured and crystallizes in the tetragonal P-42c space group. Ta(1) is bonded to four equivalent Se(1) atoms to form TaSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent In(1)Se4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to four equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Ta(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent In(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to four equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with four equivalent Ta(1)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with four equivalent In(1)Se4 tetrahedra. In(1) is bonded to four equivalent Se(1) atoms to form InSe4 tetrahedra that share corners with four equivalent Ta(1)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with four equivalent Cu(2)Se4 tetrahedra. Se(1) is bonded to one Ta(1), one Cu(1), one Cu(2), and one In(1) atom to form corner-sharing SeTaInCu2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TaIn(CuSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.819
_cell_length_b   5.819
_cell_length_c   12.217
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   413.674
_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  0.000  0.000  0.000  1.0
  Ta  Ta1  1  0.000  0.000  0.500  1.0
  In  In2  1  0.500  0.000  0.250  1.0
  In  In3  1  0.000  0.500  0.750  1.0
  Cu  Cu4  1  0.000  0.500  0.250  1.0
  Cu  Cu5  1  0.500  0.000  0.750  1.0
  Cu  Cu6  1  0.500  0.500  0.000  1.0
  Cu  Cu7  1  0.500  0.500  0.500  1.0
  Se  Se8  1  0.212  0.281  0.111  1.0
  Se  Se9  1  0.788  0.719  0.111  1.0
  Se  Se10  1  0.281  0.788  0.889  1.0
  Se  Se11  1  0.788  0.281  0.389  1.0
  Se  Se12  1  0.719  0.212  0.889  1.0
  Se  Se13  1  0.212  0.719  0.389  1.0
  Se  Se14  1  0.719  0.788  0.611  1.0
  Se  Se15  1  0.281  0.212  0.611  1.0
[/CIF]
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