The compound described by Cs2Cu2Sb2Se5 crystallizes in the triclinic P-1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 10-coordinate geometry to one Cu(1), one Sb(1), one Se(1), one Se(2), one Se(5), two equivalent Se(3), and three equivalent Se(4) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(5) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Cs(1), one Se(1), one Se(3), and two equivalent Se(5) atoms to form distorted CuCsSe4 tetrahedra that share corners with three equivalent Se(4)Cs4Sb2 octahedra and  an edgeedge with one Cu(1)CsSe4 tetrahedra. The corner-sharing octahedral tilt angles range from 25-93°. In the second Cu site, Cu(2) is bonded in a 4-coordinate geometry to one Se(2), one Se(5), and two equivalent Se(1) atoms. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a distorted trigonal non-coplanar geometry to one Cs(1), one Se(2), one Se(3), and one Se(4) atom. In the second Sb site, Sb(2) is bonded in a 3-coordinate geometry to one Se(1), one Se(3), one Se(4), and one Se(5) atom. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to one Cs(1), two equivalent Cs(2), one Cu(1), two equivalent Cu(2), and one Sb(2) atom. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Cs(1), two equivalent Cs(2), one Cu(2), and one Sb(1) atom. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Cs(2), two equivalent Cs(1), one Cu(1), one Sb(1), and one Sb(2) atom. In the fourth Se site, Se(4) is bonded to one Cs(2), three equivalent Cs(1), one Sb(1), and one Sb(2) atom to form distorted SeCs4Sb2 octahedra that share corners with two equivalent Se(4)Cs4Sb2 octahedra, corners with three equivalent Cu(1)CsSe4 tetrahedra, and edges with two equivalent Se(4)Cs4Sb2 octahedra. The corner-sharing octahedral tilt angles are 3°. In the fifth Se site, Se(5) is bonded in a 7-coordinate geometry to one Cs(1), two equivalent Cs(2), one Cu(2), two equivalent Cu(1), and one Sb(2) atom. is represented by the CIF card [CIF]
data_Cs2Cu2Sb2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.753
_cell_length_b   8.924
_cell_length_c   10.438
_cell_angle_alpha   91.773
_cell_angle_beta   91.790
_cell_angle_gamma   102.921
_symmetry_Int_Tables_number   1
_cell_volume   703.024
_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
  Cs  Cs0  1  0.736  0.804  0.906  1.0
  Cs  Cs1  1  0.264  0.196  0.094  1.0
  Cs  Cs2  1  0.265  0.057  0.613  1.0
  Cs  Cs3  1  0.735  0.943  0.387  1.0
  Cu  Cu4  1  0.597  0.492  0.612  1.0
  Cu  Cu5  1  0.403  0.508  0.388  1.0
  Cu  Cu6  1  0.872  0.363  0.569  1.0
  Cu  Cu7  1  0.128  0.637  0.431  1.0
  Sb  Sb8  1  0.801  0.360  0.882  1.0
  Sb  Sb9  1  0.199  0.640  0.118  1.0
  Sb  Sb10  1  0.816  0.422  0.261  1.0
  Sb  Sb11  1  0.184  0.578  0.739  1.0
  Se  Se12  1  0.918  0.655  0.612  1.0
  Se  Se13  1  0.082  0.345  0.388  1.0
  Se  Se14  1  0.857  0.158  0.719  1.0
  Se  Se15  1  0.143  0.842  0.281  1.0
  Se  Se16  1  0.487  0.384  0.814  1.0
  Se  Se17  1  0.513  0.616  0.186  1.0
  Se  Se18  1  0.745  0.184  0.088  1.0
  Se  Se19  1  0.255  0.816  0.912  1.0
  Se  Se20  1  0.573  0.304  0.424  1.0
  Se  Se21  1  0.427  0.696  0.576  1.0
[/CIF]
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The compound described by Cs2Cu2Sb2Se5 crystallizes in the triclinic P-1 space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 10-coordinate geometry to one Cu(1), one Sb(1), one Se(1), one Se(2), one Se(5), two equivalent Se(3), and three equivalent Se(4) atoms. In the second Cs site, Cs(2) is bonded in a 8-coordinate geometry to one Se(3), one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent Se(5) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Cs(1), one Se(1), one Se(3), and two equivalent Se(5) atoms to form distorted CuCsSe4 tetrahedra that share corners with three equivalent Se(4)Cs4Sb2 octahedra and  an edgeedge with one Cu(1)CsSe4 tetrahedra. The corner-sharing octahedral tilt angles range from 25-93°. In the second Cu site, Cu(2) is bonded in a 4-coordinate geometry to one Se(2), one Se(5), and two equivalent Se(1) atoms. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded in a distorted trigonal non-coplanar geometry to one Cs(1), one Se(2), one Se(3), and one Se(4) atom. In the second Sb site, Sb(2) is bonded in a 3-coordinate geometry to one Se(1), one Se(3), one Se(4), and one Se(5) atom. There are five inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to one Cs(1), two equivalent Cs(2), one Cu(1), two equivalent Cu(2), and one Sb(2) atom. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Cs(1), two equivalent Cs(2), one Cu(2), and one Sb(1) atom. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Cs(2), two equivalent Cs(1), one Cu(1), one Sb(1), and one Sb(2) atom. In the fourth Se site, Se(4) is bonded to one Cs(2), three equivalent Cs(1), one Sb(1), and one Sb(2) atom to form distorted SeCs4Sb2 octahedra that share corners with two equivalent Se(4)Cs4Sb2 octahedra, corners with three equivalent Cu(1)CsSe4 tetrahedra, and edges with two equivalent Se(4)Cs4Sb2 octahedra. The corner-sharing octahedral tilt angles are 3°. In the fifth Se site, Se(5) is bonded in a 7-coordinate geometry to one Cs(1), two equivalent Cs(2), one Cu(2), two equivalent Cu(1), and one Sb(2) atom. is represented by the CIF card [CIF]
data_Cs2Cu2Sb2Se5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.753
_cell_length_b   8.924
_cell_length_c   10.438
_cell_angle_alpha   91.773
_cell_angle_beta   91.790
_cell_angle_gamma   102.921
_symmetry_Int_Tables_number   1
_cell_volume   703.024
_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
  Cs  Cs0  1  0.736  0.804  0.906  1.0
  Cs  Cs1  1  0.264  0.196  0.094  1.0
  Cs  Cs2  1  0.265  0.057  0.613  1.0
  Cs  Cs3  1  0.735  0.943  0.387  1.0
  Cu  Cu4  1  0.597  0.492  0.612  1.0
  Cu  Cu5  1  0.403  0.508  0.388  1.0
  Cu  Cu6  1  0.872  0.363  0.569  1.0
  Cu  Cu7  1  0.128  0.637  0.431  1.0
  Sb  Sb8  1  0.801  0.360  0.882  1.0
  Sb  Sb9  1  0.199  0.640  0.118  1.0
  Sb  Sb10  1  0.816  0.422  0.261  1.0
  Sb  Sb11  1  0.184  0.578  0.739  1.0
  Se  Se12  1  0.918  0.655  0.612  1.0
  Se  Se13  1  0.082  0.345  0.388  1.0
  Se  Se14  1  0.857  0.158  0.719  1.0
  Se  Se15  1  0.143  0.842  0.281  1.0
  Se  Se16  1  0.487  0.384  0.814  1.0
  Se  Se17  1  0.513  0.616  0.186  1.0
  Se  Se18  1  0.745  0.184  0.088  1.0
  Se  Se19  1  0.255  0.816  0.912  1.0
  Se  Se20  1  0.573  0.304  0.424  1.0
  Se  Se21  1  0.427  0.696  0.576  1.0
[/CIF]
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