The structure described by Cs2GeSe4 crystallizes in the monoclinic C2/m space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to two equivalent Se(2), three equivalent Se(3), and four equivalent Se(1) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to two equivalent Se(3), three equivalent Se(2), 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 in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one Ge(1) atom. In the second Se site, Se(2) is bonded to two equivalent Cs(1), three equivalent Cs(2), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing SeCs5Ge octahedra. The corner-sharing octahedral tilt angles are 14°. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent Cs(2), three equivalent Cs(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_Cs2GeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.648
_cell_length_b   8.648
_cell_length_c   10.258
_cell_angle_alpha   62.033
_cell_angle_beta   62.033
_cell_angle_gamma   53.153
_symmetry_Int_Tables_number   1
_cell_volume   522.737
_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  0.159  0.159  0.714  1.0
  Cs  Cs1  1  0.841  0.841  0.286  1.0
  Cs  Cs2  1  0.408  0.408  0.858  1.0
  Cs  Cs3  1  0.592  0.592  0.142  1.0
  Ge  Ge4  1  0.157  0.157  0.297  1.0
  Ge  Ge5  1  0.843  0.843  0.703  1.0
  Se  Se6  1  0.838  0.334  0.466  1.0
  Se  Se7  1  0.334  0.838  0.466  1.0
  Se  Se8  1  0.162  0.666  0.534  1.0
  Se  Se9  1  0.666  0.162  0.534  1.0
  Se  Se10  1  0.126  0.126  0.103  1.0
  Se  Se11  1  0.874  0.874  0.897  1.0
  Se  Se12  1  0.315  0.315  0.270  1.0
  Se  Se13  1  0.685  0.685  0.730  1.0
[/CIF]
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The structure described by Cs2GeSe4 crystallizes in the monoclinic C2/m space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded in a 9-coordinate geometry to two equivalent Se(2), three equivalent Se(3), and four equivalent Se(1) atoms. In the second Cs site, Cs(2) is bonded in a 9-coordinate geometry to two equivalent Se(3), three equivalent Se(2), 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 in a distorted single-bond geometry to two equivalent Cs(1), two equivalent Cs(2), and one Ge(1) atom. In the second Se site, Se(2) is bonded to two equivalent Cs(1), three equivalent Cs(2), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing SeCs5Ge octahedra. The corner-sharing octahedral tilt angles are 14°. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent Cs(2), three equivalent Cs(1), and one Ge(1) atom. is represented by the CIF file [CIF]
data_Cs2GeSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.648
_cell_length_b   8.648
_cell_length_c   10.258
_cell_angle_alpha   62.033
_cell_angle_beta   62.033
_cell_angle_gamma   53.153
_symmetry_Int_Tables_number   1
_cell_volume   522.737
_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  0.159  0.159  0.714  1.0
  Cs  Cs1  1  0.841  0.841  0.286  1.0
  Cs  Cs2  1  0.408  0.408  0.858  1.0
  Cs  Cs3  1  0.592  0.592  0.142  1.0
  Ge  Ge4  1  0.157  0.157  0.297  1.0
  Ge  Ge5  1  0.843  0.843  0.703  1.0
  Se  Se6  1  0.838  0.334  0.466  1.0
  Se  Se7  1  0.334  0.838  0.466  1.0
  Se  Se8  1  0.162  0.666  0.534  1.0
  Se  Se9  1  0.666  0.162  0.534  1.0
  Se  Se10  1  0.126  0.126  0.103  1.0
  Se  Se11  1  0.874  0.874  0.897  1.0
  Se  Se12  1  0.315  0.315  0.270  1.0
  Se  Se13  1  0.685  0.685  0.730  1.0
[/CIF]
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