The material structure described by RbTa(CuSe2)2 crystallizes in the orthorhombic Ama2 space group. Rb(1) is bonded in a 9-coordinate geometry to one Se(2), four equivalent Se(1), and four equivalent Se(3) atoms. Ta(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form distorted TaSe4 tetrahedra that share edges with two equivalent Cu(1)Se4 tetrahedra and edges with two equivalent Cu(2)Se4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent Se(2) and two equivalent Se(3) atoms to form distorted CuSe4 tetrahedra that share corners with two equivalent Cu(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and edges with two equivalent Ta(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra and edges with two equivalent Ta(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to four equivalent Rb(1), one Ta(1), and one Cu(2) atom. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Rb(1), one Ta(1), one Cu(2), and two equivalent Cu(1) atoms. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent Rb(1), one Ta(1), one Cu(1), and one Cu(2) atom. is represented by the CIF card [CIF]
data_RbTa(CuSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.253
_cell_length_b   10.253
_cell_length_c   7.863
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   147.429
_symmetry_Int_Tables_number   1
_cell_volume   444.975
_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
  Rb  Rb0  1  0.486  0.118  0.750  1.0
  Rb  Rb1  1  0.118  0.486  0.250  1.0
  Ta  Ta2  1  0.439  0.651  0.750  1.0
  Ta  Ta3  1  0.651  0.439  0.250  1.0
  Cu  Cu4  1  0.559  0.559  0.500  1.0
  Cu  Cu5  1  0.559  0.559  0.000  1.0
  Cu  Cu6  1  0.148  0.940  0.250  1.0
  Cu  Cu7  1  0.940  0.148  0.750  1.0
  Se  Se8  1  0.090  0.501  0.750  1.0
  Se  Se9  1  0.302  0.296  0.250  1.0
  Se  Se10  1  0.896  0.686  0.997  1.0
  Se  Se11  1  0.686  0.896  0.003  1.0
  Se  Se12  1  0.896  0.686  0.503  1.0
  Se  Se13  1  0.686  0.896  0.497  1.0
  Se  Se14  1  0.296  0.302  0.750  1.0
  Se  Se15  1  0.501  0.090  0.250  1.0
[/CIF]
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The material structure described by RbTa(CuSe2)2 crystallizes in the orthorhombic Ama2 space group. Rb(1) is bonded in a 9-coordinate geometry to one Se(2), four equivalent Se(1), and four equivalent Se(3) atoms. Ta(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form distorted TaSe4 tetrahedra that share edges with two equivalent Cu(1)Se4 tetrahedra and edges with two equivalent Cu(2)Se4 tetrahedra. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent Se(2) and two equivalent Se(3) atoms to form distorted CuSe4 tetrahedra that share corners with two equivalent Cu(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and edges with two equivalent Ta(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra and edges with two equivalent Ta(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to four equivalent Rb(1), one Ta(1), and one Cu(2) atom. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Rb(1), one Ta(1), one Cu(2), and two equivalent Cu(1) atoms. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to two equivalent Rb(1), one Ta(1), one Cu(1), and one Cu(2) atom. is represented by the CIF card [CIF]
data_RbTa(CuSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.253
_cell_length_b   10.253
_cell_length_c   7.863
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   147.429
_symmetry_Int_Tables_number   1
_cell_volume   444.975
_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
  Rb  Rb0  1  0.486  0.118  0.750  1.0
  Rb  Rb1  1  0.118  0.486  0.250  1.0
  Ta  Ta2  1  0.439  0.651  0.750  1.0
  Ta  Ta3  1  0.651  0.439  0.250  1.0
  Cu  Cu4  1  0.559  0.559  0.500  1.0
  Cu  Cu5  1  0.559  0.559  0.000  1.0
  Cu  Cu6  1  0.148  0.940  0.250  1.0
  Cu  Cu7  1  0.940  0.148  0.750  1.0
  Se  Se8  1  0.090  0.501  0.750  1.0
  Se  Se9  1  0.302  0.296  0.250  1.0
  Se  Se10  1  0.896  0.686  0.997  1.0
  Se  Se11  1  0.686  0.896  0.003  1.0
  Se  Se12  1  0.896  0.686  0.503  1.0
  Se  Se13  1  0.686  0.896  0.497  1.0
  Se  Se14  1  0.296  0.302  0.750  1.0
  Se  Se15  1  0.501  0.090  0.250  1.0
[/CIF]
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