The material described by Ge3Sb2Te6 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one Te(2), one Te(3), one Te(4), and three equivalent Te(1) atoms to form GeTe6 octahedra that share corners with four equivalent Ge(1)Te6 octahedra, edges with two equivalent Ge(1)Te6 octahedra, edges with three equivalent Ge(2)Te6 octahedra, and edges with five equivalent Sb(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the second Ge site, Ge(2) is bonded to two equivalent Te(1), two equivalent Te(2), and two equivalent Te(3) atoms to form GeTe6 octahedra that share corners with two equivalent Ge(2)Te6 octahedra, corners with four equivalent Sb(1)Te6 octahedra, edges with four equivalent Sb(1)Te6 octahedra, and edges with six equivalent Ge(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. Sb(1) is bonded to one Te(1), one Te(2), one Te(4), and three equivalent Te(3) atoms to form SbTe6 octahedra that share corners with two equivalent Ge(2)Te6 octahedra, corners with four equivalent Sb(1)Te6 octahedra, edges with two equivalent Ge(2)Te6 octahedra, edges with two equivalent Sb(1)Te6 octahedra, and edges with five equivalent Ge(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. There are four inequivalent Te sites. In the first Te site, Te(1) is bonded to one Ge(2), three equivalent Ge(1), and one Sb(1) atom to form TeGe4Sb square pyramids that share corners with two equivalent Te(3)Ge2Sb3 square pyramids, corners with three equivalent Te(1)Ge4Sb square pyramids, edges with three equivalent Te(2)Ge4Sb2 octahedra, edges with two equivalent Te(1)Ge4Sb square pyramids, and edges with three equivalent Te(3)Ge2Sb3 square pyramids. In the second Te site, Te(2) is bonded to two equivalent Ge(1), two equivalent Ge(2), and two equivalent Sb(1) atoms to form TeGe4Sb2 octahedra that share corners with two equivalent Te(2)Ge4Sb2 octahedra, corners with four equivalent Te(3)Ge2Sb3 square pyramids, edges with four equivalent Te(3)Ge2Sb3 square pyramids, and edges with six equivalent Te(1)Ge4Sb square pyramids. The corner-sharing octahedra are not tilted. In the third Te site, Te(3) is bonded to one Ge(1), one Ge(2), and three equivalent Sb(1) atoms to form TeGe2Sb3 square pyramids that share corners with two equivalent Te(2)Ge4Sb2 octahedra, corners with two equivalent Te(1)Ge4Sb square pyramids, corners with three equivalent Te(3)Ge2Sb3 square pyramids, edges with two equivalent Te(2)Ge4Sb2 octahedra, edges with two equivalent Te(3)Ge2Sb3 square pyramids, and edges with three equivalent Te(1)Ge4Sb square pyramids. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth Te site, Te(4) is bonded in a square co-planar geometry to two equivalent Ge(1) and two equivalent Sb(1) atoms. is represented by the CIF file [CIF]
data_Ge3(SbTe3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.434
_cell_length_b   7.434
_cell_length_c   8.572
_cell_angle_alpha   73.672
_cell_angle_beta   73.672
_cell_angle_gamma   48.413
_symmetry_Int_Tables_number   1
_cell_volume   337.059
_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
  Ge  Ge0  1  0.329  0.329  0.332  1.0
  Ge  Ge1  1  0.000  0.000  0.500  1.0
  Ge  Ge2  1  0.671  0.671  0.668  1.0
  Sb  Sb3  1  0.667  0.667  0.163  1.0
  Sb  Sb4  1  0.333  0.333  0.837  1.0
  Te  Te5  1  0.832  0.832  0.344  1.0
  Te  Te6  1  0.500  0.500  0.500  1.0
  Te  Te7  1  0.835  0.835  0.824  1.0
  Te  Te8  1  0.500  0.500  0.000  1.0
  Te  Te9  1  0.168  0.168  0.656  1.0
  Te  Te10  1  0.165  0.165  0.176  1.0
[/CIF]
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The material described by Ge3Sb2Te6 crystallizes in the monoclinic C2/m space group. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one Te(2), one Te(3), one Te(4), and three equivalent Te(1) atoms to form GeTe6 octahedra that share corners with four equivalent Ge(1)Te6 octahedra, edges with two equivalent Ge(1)Te6 octahedra, edges with three equivalent Ge(2)Te6 octahedra, and edges with five equivalent Sb(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the second Ge site, Ge(2) is bonded to two equivalent Te(1), two equivalent Te(2), and two equivalent Te(3) atoms to form GeTe6 octahedra that share corners with two equivalent Ge(2)Te6 octahedra, corners with four equivalent Sb(1)Te6 octahedra, edges with four equivalent Sb(1)Te6 octahedra, and edges with six equivalent Ge(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. Sb(1) is bonded to one Te(1), one Te(2), one Te(4), and three equivalent Te(3) atoms to form SbTe6 octahedra that share corners with two equivalent Ge(2)Te6 octahedra, corners with four equivalent Sb(1)Te6 octahedra, edges with two equivalent Ge(2)Te6 octahedra, edges with two equivalent Sb(1)Te6 octahedra, and edges with five equivalent Ge(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. There are four inequivalent Te sites. In the first Te site, Te(1) is bonded to one Ge(2), three equivalent Ge(1), and one Sb(1) atom to form TeGe4Sb square pyramids that share corners with two equivalent Te(3)Ge2Sb3 square pyramids, corners with three equivalent Te(1)Ge4Sb square pyramids, edges with three equivalent Te(2)Ge4Sb2 octahedra, edges with two equivalent Te(1)Ge4Sb square pyramids, and edges with three equivalent Te(3)Ge2Sb3 square pyramids. In the second Te site, Te(2) is bonded to two equivalent Ge(1), two equivalent Ge(2), and two equivalent Sb(1) atoms to form TeGe4Sb2 octahedra that share corners with two equivalent Te(2)Ge4Sb2 octahedra, corners with four equivalent Te(3)Ge2Sb3 square pyramids, edges with four equivalent Te(3)Ge2Sb3 square pyramids, and edges with six equivalent Te(1)Ge4Sb square pyramids. The corner-sharing octahedra are not tilted. In the third Te site, Te(3) is bonded to one Ge(1), one Ge(2), and three equivalent Sb(1) atoms to form TeGe2Sb3 square pyramids that share corners with two equivalent Te(2)Ge4Sb2 octahedra, corners with two equivalent Te(1)Ge4Sb square pyramids, corners with three equivalent Te(3)Ge2Sb3 square pyramids, edges with two equivalent Te(2)Ge4Sb2 octahedra, edges with two equivalent Te(3)Ge2Sb3 square pyramids, and edges with three equivalent Te(1)Ge4Sb square pyramids. The corner-sharing octahedral tilt angles range from 0-1°. In the fourth Te site, Te(4) is bonded in a square co-planar geometry to two equivalent Ge(1) and two equivalent Sb(1) atoms. is represented by the CIF file [CIF]
data_Ge3(SbTe3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.434
_cell_length_b   7.434
_cell_length_c   8.572
_cell_angle_alpha   73.672
_cell_angle_beta   73.672
_cell_angle_gamma   48.413
_symmetry_Int_Tables_number   1
_cell_volume   337.059
_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
  Ge  Ge0  1  0.329  0.329  0.332  1.0
  Ge  Ge1  1  0.000  0.000  0.500  1.0
  Ge  Ge2  1  0.671  0.671  0.668  1.0
  Sb  Sb3  1  0.667  0.667  0.163  1.0
  Sb  Sb4  1  0.333  0.333  0.837  1.0
  Te  Te5  1  0.832  0.832  0.344  1.0
  Te  Te6  1  0.500  0.500  0.500  1.0
  Te  Te7  1  0.835  0.835  0.824  1.0
  Te  Te8  1  0.500  0.500  0.000  1.0
  Te  Te9  1  0.168  0.168  0.656  1.0
  Te  Te10  1  0.165  0.165  0.176  1.0
[/CIF]
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