The structure described by Cu4Zn(SnSe4)2 crystallizes in the monoclinic C2 space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with three equivalent Zn(1)Se4 tetrahedra, and corners with four equivalent Sn(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(1), one Se(2), and two equivalent Se(4) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Zn(1)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent Sn(1)Se4 tetrahedra. Zn(1) is bonded to two equivalent Se(1) and two equivalent Se(3) atoms to form ZnSe4 tetrahedra that share corners with two equivalent Cu(2)Se4 tetrahedra, corners with four equivalent Sn(1)Se4 tetrahedra, and corners with six equivalent Cu(1)Se4 tetrahedra. Sn(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(4) atom to form SnSe4 tetrahedra that share corners with two equivalent Zn(1)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with four equivalent Cu(2)Se4 tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cu(1), one Cu(2), one Zn(1), and one Sn(1) atom to form corner-sharing SeZnCu2Sn tetrahedra. In the second Se site, Se(2) is bonded in a trigonal non-coplanar geometry to one Cu(1), one Cu(2), and one Sn(1) atom. In the third Se site, Se(3) is bonded to two equivalent Cu(1), one Zn(1), and one Sn(1) atom to form corner-sharing SeZnCu2Sn tetrahedra. In the fourth Se site, Se(4) is bonded in a trigonal non-coplanar geometry to two equivalent Cu(2) and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_ZnCu4(SnSe4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.965
_cell_length_b   6.965
_cell_length_c   11.403
_cell_angle_alpha   65.921
_cell_angle_beta   65.921
_cell_angle_gamma   48.378
_symmetry_Int_Tables_number   1
_cell_volume   369.854
_cell_formula_units_Z   1
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
  Zn  Zn0  1  0.001  0.999  0.500  1.0
  Cu  Cu1  1  0.764  0.742  0.370  1.0
  Cu  Cu2  1  0.738  0.754  0.881  1.0
  Cu  Cu3  1  0.246  0.262  0.119  1.0
  Cu  Cu4  1  0.258  0.236  0.630  1.0
  Sn  Sn5  1  0.503  0.497  0.242  1.0
  Sn  Sn6  1  0.503  0.497  0.758  1.0
  Se  Se7  1  0.379  0.891  0.311  1.0
  Se  Se8  1  0.366  0.898  0.817  1.0
  Se  Se9  1  0.627  0.103  0.445  1.0
  Se  Se10  1  0.637  0.102  0.949  1.0
  Se  Se11  1  0.102  0.634  0.183  1.0
  Se  Se12  1  0.109  0.621  0.689  1.0
  Se  Se13  1  0.898  0.363  0.051  1.0
  Se  Se14  1  0.897  0.373  0.555  1.0
[/CIF]
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The structure described by Cu4Zn(SnSe4)2 crystallizes in the monoclinic C2 space group. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form CuSe4 tetrahedra that share corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, corners with three equivalent Zn(1)Se4 tetrahedra, and corners with four equivalent Sn(1)Se4 tetrahedra. In the second Cu site, Cu(2) is bonded to one Se(1), one Se(2), and two equivalent Se(4) atoms to form CuSe4 tetrahedra that share  a cornercorner with one Zn(1)Se4 tetrahedra, corners with two equivalent Cu(1)Se4 tetrahedra, corners with two equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent Sn(1)Se4 tetrahedra. Zn(1) is bonded to two equivalent Se(1) and two equivalent Se(3) atoms to form ZnSe4 tetrahedra that share corners with two equivalent Cu(2)Se4 tetrahedra, corners with four equivalent Sn(1)Se4 tetrahedra, and corners with six equivalent Cu(1)Se4 tetrahedra. Sn(1) is bonded to one Se(1), one Se(2), one Se(3), and one Se(4) atom to form SnSe4 tetrahedra that share corners with two equivalent Zn(1)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with four equivalent Cu(2)Se4 tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded to one Cu(1), one Cu(2), one Zn(1), and one Sn(1) atom to form corner-sharing SeZnCu2Sn tetrahedra. In the second Se site, Se(2) is bonded in a trigonal non-coplanar geometry to one Cu(1), one Cu(2), and one Sn(1) atom. In the third Se site, Se(3) is bonded to two equivalent Cu(1), one Zn(1), and one Sn(1) atom to form corner-sharing SeZnCu2Sn tetrahedra. In the fourth Se site, Se(4) is bonded in a trigonal non-coplanar geometry to two equivalent Cu(2) and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_ZnCu4(SnSe4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.965
_cell_length_b   6.965
_cell_length_c   11.403
_cell_angle_alpha   65.921
_cell_angle_beta   65.921
_cell_angle_gamma   48.378
_symmetry_Int_Tables_number   1
_cell_volume   369.854
_cell_formula_units_Z   1
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
  Zn  Zn0  1  0.001  0.999  0.500  1.0
  Cu  Cu1  1  0.764  0.742  0.370  1.0
  Cu  Cu2  1  0.738  0.754  0.881  1.0
  Cu  Cu3  1  0.246  0.262  0.119  1.0
  Cu  Cu4  1  0.258  0.236  0.630  1.0
  Sn  Sn5  1  0.503  0.497  0.242  1.0
  Sn  Sn6  1  0.503  0.497  0.758  1.0
  Se  Se7  1  0.379  0.891  0.311  1.0
  Se  Se8  1  0.366  0.898  0.817  1.0
  Se  Se9  1  0.627  0.103  0.445  1.0
  Se  Se10  1  0.637  0.102  0.949  1.0
  Se  Se11  1  0.102  0.634  0.183  1.0
  Se  Se12  1  0.109  0.621  0.689  1.0
  Se  Se13  1  0.898  0.363  0.051  1.0
  Se  Se14  1  0.897  0.373  0.555  1.0
[/CIF]
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