The material structure described by Cu2FeGeSe4 is Stannite structured and crystallizes in the tetragonal I-42m space group. Fe(1) is bonded to four equivalent Se(1) atoms to form FeSe4 tetrahedra that share corners with four equivalent Ge(1)Se4 tetrahedra and corners with eight equivalent Cu(1)Se4 tetrahedra. Cu(1) is bonded to four equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with four equivalent Fe(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 Fe(1)Se4 tetrahedra and corners with eight equivalent Cu(1)Se4 tetrahedra. Se(1) is bonded to one Fe(1), two equivalent Cu(1), and one Ge(1) atom to form corner-sharing SeFeCu2Ge tetrahedra. is represented by the CIF file [CIF]
data_FeCu2GeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.858
_cell_length_b   6.858
_cell_length_c   6.858
_cell_angle_alpha   131.402
_cell_angle_beta   131.402
_cell_angle_gamma   71.175
_symmetry_Int_Tables_number   1
_cell_volume   177.681
_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
  Fe  Fe0  1  0.000  0.000  0.000  1.0
  Cu  Cu1  1  0.750  0.250  0.500  1.0
  Cu  Cu2  1  0.250  0.750  0.500  1.0
  Ge  Ge3  1  0.500  0.500  0.000  1.0
  Se  Se4  1  0.374  0.883  0.000  1.0
  Se  Se5  1  0.883  0.374  0.000  1.0
  Se  Se6  1  0.626  0.626  0.509  1.0
  Se  Se7  1  0.117  0.117  0.491  1.0
[/CIF]
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The material structure described by Cu2FeGeSe4 is Stannite structured and crystallizes in the tetragonal I-42m space group. Fe(1) is bonded to four equivalent Se(1) atoms to form FeSe4 tetrahedra that share corners with four equivalent Ge(1)Se4 tetrahedra and corners with eight equivalent Cu(1)Se4 tetrahedra. Cu(1) is bonded to four equivalent Se(1) atoms to form CuSe4 tetrahedra that share corners with four equivalent Fe(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 Fe(1)Se4 tetrahedra and corners with eight equivalent Cu(1)Se4 tetrahedra. Se(1) is bonded to one Fe(1), two equivalent Cu(1), and one Ge(1) atom to form corner-sharing SeFeCu2Ge tetrahedra. is represented by the CIF file [CIF]
data_FeCu2GeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.858
_cell_length_b   6.858
_cell_length_c   6.858
_cell_angle_alpha   131.402
_cell_angle_beta   131.402
_cell_angle_gamma   71.175
_symmetry_Int_Tables_number   1
_cell_volume   177.681
_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
  Fe  Fe0  1  0.000  0.000  0.000  1.0
  Cu  Cu1  1  0.750  0.250  0.500  1.0
  Cu  Cu2  1  0.250  0.750  0.500  1.0
  Ge  Ge3  1  0.500  0.500  0.000  1.0
  Se  Se4  1  0.374  0.883  0.000  1.0
  Se  Se5  1  0.883  0.374  0.000  1.0
  Se  Se6  1  0.626  0.626  0.509  1.0
  Se  Se7  1  0.117  0.117  0.491  1.0
[/CIF]
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