The material described by Cs2GeSe3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to two equivalent Se(2), two equivalent Se(3), and three equivalent Se(1) atoms to form distorted CsSe7 pentagonal bipyramids that share corners with two equivalent Cs(1)Se7 pentagonal bipyramids, corners with three equivalent Ge(1)Se4 tetrahedra, edges with four equivalent Cs(1)Se7 pentagonal bipyramids, and edges with three equivalent Ge(1)Se4 tetrahedra. In the second Cs site, Cs(2) is bonded in a 7-coordinate geometry to two equivalent Se(1), two equivalent Se(3), and three equivalent Se(2) atoms. Ge(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form GeSe4 tetrahedra that share corners with three equivalent Cs(1)Se7 pentagonal bipyramids, edges with three equivalent Cs(1)Se7 pentagonal bipyramids, and  an edgeedge with one Ge(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Cs(2), three equivalent Cs(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing SeCs5Ge octahedra. The corner-sharing octahedral tilt angles range from 3-76°. 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 range from 3-76°. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent Cs(1), two equivalent Cs(2), and two equivalent Ge(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs2GeSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.136
_cell_length_b   8.136
_cell_length_c   10.473
_cell_angle_alpha   59.757
_cell_angle_beta   59.757
_cell_angle_gamma   54.937
_symmetry_Int_Tables_number   1
_cell_volume   467.191
_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  0.583  0.583  0.138  1.0
  Cs  Cs1  1  0.417  0.417  0.862  1.0
  Cs  Cs2  1  0.804  0.804  0.320  1.0
  Cs  Cs3  1  0.196  0.196  0.680  1.0
  Ge  Ge4  1  0.116  0.116  0.319  1.0
  Ge  Ge5  1  0.884  0.884  0.681  1.0
  Se  Se6  1  0.110  0.110  0.104  1.0
  Se  Se7  1  0.890  0.890  0.896  1.0
  Se  Se8  1  0.292  0.292  0.275  1.0
  Se  Se9  1  0.708  0.708  0.725  1.0
  Se  Se10  1  0.238  0.762  0.500  1.0
  Se  Se11  1  0.762  0.238  0.500  1.0
[/CIF]
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The material described by Cs2GeSe3 crystallizes in the monoclinic C2/m space group. There are two inequivalent Cs sites. In the first Cs site, Cs(1) is bonded to two equivalent Se(2), two equivalent Se(3), and three equivalent Se(1) atoms to form distorted CsSe7 pentagonal bipyramids that share corners with two equivalent Cs(1)Se7 pentagonal bipyramids, corners with three equivalent Ge(1)Se4 tetrahedra, edges with four equivalent Cs(1)Se7 pentagonal bipyramids, and edges with three equivalent Ge(1)Se4 tetrahedra. In the second Cs site, Cs(2) is bonded in a 7-coordinate geometry to two equivalent Se(1), two equivalent Se(3), and three equivalent Se(2) atoms. Ge(1) is bonded to one Se(1), one Se(2), and two equivalent Se(3) atoms to form GeSe4 tetrahedra that share corners with three equivalent Cs(1)Se7 pentagonal bipyramids, edges with three equivalent Cs(1)Se7 pentagonal bipyramids, and  an edgeedge with one Ge(1)Se4 tetrahedra. There are three inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Cs(2), three equivalent Cs(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing SeCs5Ge octahedra. The corner-sharing octahedral tilt angles range from 3-76°. 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 range from 3-76°. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to two equivalent Cs(1), two equivalent Cs(2), and two equivalent Ge(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Cs2GeSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.136
_cell_length_b   8.136
_cell_length_c   10.473
_cell_angle_alpha   59.757
_cell_angle_beta   59.757
_cell_angle_gamma   54.937
_symmetry_Int_Tables_number   1
_cell_volume   467.191
_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  0.583  0.583  0.138  1.0
  Cs  Cs1  1  0.417  0.417  0.862  1.0
  Cs  Cs2  1  0.804  0.804  0.320  1.0
  Cs  Cs3  1  0.196  0.196  0.680  1.0
  Ge  Ge4  1  0.116  0.116  0.319  1.0
  Ge  Ge5  1  0.884  0.884  0.681  1.0
  Se  Se6  1  0.110  0.110  0.104  1.0
  Se  Se7  1  0.890  0.890  0.896  1.0
  Se  Se8  1  0.292  0.292  0.275  1.0
  Se  Se9  1  0.708  0.708  0.725  1.0
  Se  Se10  1  0.238  0.762  0.500  1.0
  Se  Se11  1  0.762  0.238  0.500  1.0
[/CIF]
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