The material described by CsCu3TiSe4 crystallizes in the monoclinic P2_1/m space group. Cs(1) is bonded in a 9-coordinate geometry to one Se(2), four equivalent Se(1), and four equivalent Se(3) atoms. Ti(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form distorted TiSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra, 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(1) and two equivalent Se(2) atoms to form distorted CuSe4 tetrahedra that share corners with two equivalent Ti(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra,  an edgeedge with one Ti(1)Se4 tetrahedra,  an edgeedge with one Cu(2)Se4 tetrahedra, and edges with two equivalent Cu(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra, edges with two equivalent Ti(1)Se4 tetrahedra, and edges with two equivalent Cu(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent Cs(1), one Ti(1), one Cu(2), and two equivalent Cu(1) atoms. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to one Cs(1), one Ti(1), one Cu(2), and four equivalent Cu(1) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to four equivalent Cs(1), one Ti(1), and one Cu(2) atom. is represented by the CIF file [CIF]
data_CsTiCu3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.855
_cell_length_b   5.825
_cell_length_c   10.395
_cell_angle_alpha   73.699
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   456.542
_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  0.250  0.178  0.622  1.0
  Cs  Cs1  1  0.750  0.822  0.378  1.0
  Ti  Ti2  1  0.750  0.352  0.795  1.0
  Ti  Ti3  1  0.250  0.648  0.205  1.0
  Cu  Cu4  1  0.506  0.722  0.998  1.0
  Cu  Cu5  1  0.750  0.850  0.800  1.0
  Cu  Cu6  1  0.250  0.150  0.200  1.0
  Cu  Cu7  1  0.494  0.278  0.002  1.0
  Cu  Cu8  1  0.006  0.278  0.002  1.0
  Cu  Cu9  1  0.994  0.722  0.998  1.0
  Se  Se10  1  0.497  0.598  0.789  1.0
  Se  Se11  1  0.997  0.402  0.211  1.0
  Se  Se12  1  0.003  0.598  0.789  1.0
  Se  Se13  1  0.503  0.402  0.211  1.0
  Se  Se14  1  0.250  0.982  0.997  1.0
  Se  Se15  1  0.750  0.018  0.003  1.0
  Se  Se16  1  0.250  0.798  0.394  1.0
  Se  Se17  1  0.750  0.202  0.606  1.0
[/CIF]
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The material described by CsCu3TiSe4 crystallizes in the monoclinic P2_1/m space group. Cs(1) is bonded in a 9-coordinate geometry to one Se(2), four equivalent Se(1), and four equivalent Se(3) atoms. Ti(1) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form distorted TiSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra, 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(1) and two equivalent Se(2) atoms to form distorted CuSe4 tetrahedra that share corners with two equivalent Ti(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra,  an edgeedge with one Ti(1)Se4 tetrahedra,  an edgeedge with one Cu(2)Se4 tetrahedra, and edges with two equivalent Cu(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(2), one Se(3), and two equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra, edges with two equivalent Ti(1)Se4 tetrahedra, and edges with two equivalent Cu(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to two equivalent Cs(1), one Ti(1), one Cu(2), and two equivalent Cu(1) atoms. In the second Se site, Se(2) is bonded in a 7-coordinate geometry to one Cs(1), one Ti(1), one Cu(2), and four equivalent Cu(1) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to four equivalent Cs(1), one Ti(1), and one Cu(2) atom. is represented by the CIF file [CIF]
data_CsTiCu3Se4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.855
_cell_length_b   5.825
_cell_length_c   10.395
_cell_angle_alpha   73.699
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   456.542
_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  0.250  0.178  0.622  1.0
  Cs  Cs1  1  0.750  0.822  0.378  1.0
  Ti  Ti2  1  0.750  0.352  0.795  1.0
  Ti  Ti3  1  0.250  0.648  0.205  1.0
  Cu  Cu4  1  0.506  0.722  0.998  1.0
  Cu  Cu5  1  0.750  0.850  0.800  1.0
  Cu  Cu6  1  0.250  0.150  0.200  1.0
  Cu  Cu7  1  0.494  0.278  0.002  1.0
  Cu  Cu8  1  0.006  0.278  0.002  1.0
  Cu  Cu9  1  0.994  0.722  0.998  1.0
  Se  Se10  1  0.497  0.598  0.789  1.0
  Se  Se11  1  0.997  0.402  0.211  1.0
  Se  Se12  1  0.003  0.598  0.789  1.0
  Se  Se13  1  0.503  0.402  0.211  1.0
  Se  Se14  1  0.250  0.982  0.997  1.0
  Se  Se15  1  0.750  0.018  0.003  1.0
  Se  Se16  1  0.250  0.798  0.394  1.0
  Se  Se17  1  0.750  0.202  0.606  1.0
[/CIF]
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