The crystal structure described by Cu2CoGeSe4 is Stannite-like structured and crystallizes in the tetragonal I-4 space group. Co(1) is bonded to four equivalent Se(1) atoms to form CoSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent Ge(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 CuSe4 tetrahedra that share corners with four equivalent Co(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent Ge(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 Co(1)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with four equivalent Ge(1)Se4 tetrahedra. Ge(1) is bonded to four equivalent Se(1) atoms to form GeSe4 tetrahedra that share corners with four equivalent Co(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 Co(1), one Cu(1), one Cu(2), and one Ge(1) atom to form corner-sharing SeCoCu2Ge tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CoCu2GeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.844
_cell_length_b   6.844
_cell_length_c   6.844
_cell_angle_alpha   131.702
_cell_angle_beta   131.702
_cell_angle_gamma   70.700
_symmetry_Int_Tables_number   1
_cell_volume   175.074
_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
  Co  Co0  1  0.500  0.500  0.000  1.0
  Cu  Cu1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.250  0.750  0.500  1.0
  Ge  Ge3  1  0.750  0.250  0.500  1.0
  Se  Se4  1  0.622  0.129  0.994  1.0
  Se  Se5  1  0.871  0.865  0.493  1.0
  Se  Se6  1  0.135  0.628  0.006  1.0
  Se  Se7  1  0.372  0.378  0.507  1.0
[/CIF]
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The crystal structure described by Cu2CoGeSe4 is Stannite-like structured and crystallizes in the tetragonal I-4 space group. Co(1) is bonded to four equivalent Se(1) atoms to form CoSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent Ge(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 CuSe4 tetrahedra that share corners with four equivalent Co(1)Se4 tetrahedra, corners with four equivalent Cu(2)Se4 tetrahedra, and corners with four equivalent Ge(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 Co(1)Se4 tetrahedra, corners with four equivalent Cu(1)Se4 tetrahedra, and corners with four equivalent Ge(1)Se4 tetrahedra. Ge(1) is bonded to four equivalent Se(1) atoms to form GeSe4 tetrahedra that share corners with four equivalent Co(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 Co(1), one Cu(1), one Cu(2), and one Ge(1) atom to form corner-sharing SeCoCu2Ge tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_CoCu2GeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.844
_cell_length_b   6.844
_cell_length_c   6.844
_cell_angle_alpha   131.702
_cell_angle_beta   131.702
_cell_angle_gamma   70.700
_symmetry_Int_Tables_number   1
_cell_volume   175.074
_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
  Co  Co0  1  0.500  0.500  0.000  1.0
  Cu  Cu1  1  0.000  0.000  0.000  1.0
  Cu  Cu2  1  0.250  0.750  0.500  1.0
  Ge  Ge3  1  0.750  0.250  0.500  1.0
  Se  Se4  1  0.622  0.129  0.994  1.0
  Se  Se5  1  0.871  0.865  0.493  1.0
  Se  Se6  1  0.135  0.628  0.006  1.0
  Se  Se7  1  0.372  0.378  0.507  1.0
[/CIF]
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