The material structure described by Eu2GeSe4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 6-coordinate geometry to one Se(3), three equivalent Se(2), and four equivalent Se(1) atoms. In the second Eu site, Eu(2) is bonded in a 8-coordinate geometry to one Se(2), three equivalent Se(3), and four equivalent Se(1) atoms. Ge(1) is bonded in a tetrahedral geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Eu(1), two equivalent Eu(2), and one Ge(1) atom to form a mixture of corner, edge, and face-sharing SeEu4Ge square pyramids. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Eu(2), three equivalent Eu(1), and one Ge(1) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to one Eu(1), three equivalent Eu(2), and one Ge(1) atom. is represented by the CIF file [CIF]
data_Eu2GeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.024
_cell_length_b   7.009
_cell_length_c   8.432
_cell_angle_alpha   72.192
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   395.218
_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
  Eu  Eu0  1  0.750  0.272  0.056  1.0
  Eu  Eu1  1  0.250  0.728  0.944  1.0
  Eu  Eu2  1  0.250  0.752  0.437  1.0
  Eu  Eu3  1  0.750  0.248  0.563  1.0
  Ge  Ge4  1  0.750  0.731  0.197  1.0
  Ge  Ge5  1  0.250  0.269  0.803  1.0
  Se  Se6  1  0.491  0.498  0.258  1.0
  Se  Se7  1  0.750  0.914  0.907  1.0
  Se  Se8  1  0.250  0.086  0.093  1.0
  Se  Se9  1  0.009  0.498  0.258  1.0
  Se  Se10  1  0.250  0.075  0.615  1.0
  Se  Se11  1  0.991  0.502  0.742  1.0
  Se  Se12  1  0.509  0.502  0.742  1.0
  Se  Se13  1  0.750  0.925  0.385  1.0
[/CIF]
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The material structure described by Eu2GeSe4 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 6-coordinate geometry to one Se(3), three equivalent Se(2), and four equivalent Se(1) atoms. In the second Eu site, Eu(2) is bonded in a 8-coordinate geometry to one Se(2), three equivalent Se(3), and four equivalent Se(1) atoms. Ge(1) is bonded in a tetrahedral geometry to one Se(2), one Se(3), and two equivalent Se(1) atoms. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Eu(1), two equivalent Eu(2), and one Ge(1) atom to form a mixture of corner, edge, and face-sharing SeEu4Ge square pyramids. In the second Se site, Se(2) is bonded in a 5-coordinate geometry to one Eu(2), three equivalent Eu(1), and one Ge(1) atom. In the third Se site, Se(3) is bonded in a 5-coordinate geometry to one Eu(1), three equivalent Eu(2), and one Ge(1) atom. is represented by the CIF file [CIF]
data_Eu2GeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.024
_cell_length_b   7.009
_cell_length_c   8.432
_cell_angle_alpha   72.192
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   395.218
_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
  Eu  Eu0  1  0.750  0.272  0.056  1.0
  Eu  Eu1  1  0.250  0.728  0.944  1.0
  Eu  Eu2  1  0.250  0.752  0.437  1.0
  Eu  Eu3  1  0.750  0.248  0.563  1.0
  Ge  Ge4  1  0.750  0.731  0.197  1.0
  Ge  Ge5  1  0.250  0.269  0.803  1.0
  Se  Se6  1  0.491  0.498  0.258  1.0
  Se  Se7  1  0.750  0.914  0.907  1.0
  Se  Se8  1  0.250  0.086  0.093  1.0
  Se  Se9  1  0.009  0.498  0.258  1.0
  Se  Se10  1  0.250  0.075  0.615  1.0
  Se  Se11  1  0.991  0.502  0.742  1.0
  Se  Se12  1  0.509  0.502  0.742  1.0
  Se  Se13  1  0.750  0.925  0.385  1.0
[/CIF]
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