The material structure described by Pb5Te4Se is Caswellsilverite-like structured and crystallizes in the tetragonal I4/mmm space group. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Te(1) and five equivalent Te(2) atoms to form PbTe6 octahedra that share  a cornercorner with one Pb(3)Te2Se4 octahedra,  a cornercorner with one Pb(2)Te5Se octahedra, corners with four equivalent Pb(1)Te6 octahedra, edges with four equivalent Pb(2)Te5Se octahedra, and edges with eight equivalent Pb(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Pb site, Pb(2) is bonded to one Te(2), four equivalent Te(1), and one Se(1) atom to form PbTe5Se octahedra that share  a cornercorner with one Pb(1)Te6 octahedra, corners with five equivalent Pb(2)Te5Se octahedra, edges with four equivalent Pb(3)Te2Se4 octahedra, edges with four equivalent Pb(2)Te5Se octahedra, and edges with four equivalent Pb(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the third Pb site, Pb(3) is bonded to two equivalent Te(1) and four equivalent Se(1) atoms to form PbTe2Se4 octahedra that share corners with two equivalent Pb(1)Te6 octahedra, corners with four equivalent Pb(3)Te2Se4 octahedra, edges with four equivalent Pb(3)Te2Se4 octahedra, and edges with eight equivalent Pb(2)Te5Se octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Te sites. In the first Te site, Te(1) is bonded to one Pb(1), one Pb(3), and four equivalent Pb(2) atoms to form TePb6 octahedra that share  a cornercorner with one Te(2)Pb6 octahedra, corners with five equivalent Te(1)Pb6 octahedra, edges with four equivalent Te(1)Pb6 octahedra, edges with four equivalent Te(2)Pb6 octahedra, and edges with four equivalent Se(1)Pb6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Te site, Te(2) is bonded to one Pb(2) and five equivalent Pb(1) atoms to form TePb6 octahedra that share  a cornercorner with one Te(1)Pb6 octahedra,  a cornercorner with one Se(1)Pb6 octahedra, corners with four equivalent Te(2)Pb6 octahedra, edges with four equivalent Te(1)Pb6 octahedra, and edges with eight equivalent Te(2)Pb6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. Se(1) is bonded to two equivalent Pb(2) and four equivalent Pb(3) atoms to form SePb6 octahedra that share corners with two equivalent Te(2)Pb6 octahedra, corners with four equivalent Se(1)Pb6 octahedra, edges with four equivalent Se(1)Pb6 octahedra, and edges with eight equivalent Te(1)Pb6 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Te4Pb5Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.802
_cell_length_b   16.802
_cell_length_c   16.802
_cell_angle_alpha   164.309
_cell_angle_beta   164.309
_cell_angle_gamma   22.261
_symmetry_Int_Tables_number   1
_cell_volume   346.912
_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
  Te  Te0  1  0.900  0.900  0.000  1.0
  Te  Te1  1  0.301  0.301  0.000  1.0
  Te  Te2  1  0.699  0.699  0.000  1.0
  Te  Te3  1  0.100  0.100  0.000  1.0
  Pb  Pb4  1  0.200  0.200  0.000  1.0
  Pb  Pb5  1  0.402  0.402  0.000  1.0
  Pb  Pb6  1  0.800  0.800  0.000  1.0
  Pb  Pb7  1  0.598  0.598  0.000  1.0
  Pb  Pb8  1  0.000  0.000  0.000  1.0
  Se  Se9  1  0.500  0.500  0.000  1.0
[/CIF]
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The material structure described by Pb5Te4Se is Caswellsilverite-like structured and crystallizes in the tetragonal I4/mmm space group. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Te(1) and five equivalent Te(2) atoms to form PbTe6 octahedra that share  a cornercorner with one Pb(3)Te2Se4 octahedra,  a cornercorner with one Pb(2)Te5Se octahedra, corners with four equivalent Pb(1)Te6 octahedra, edges with four equivalent Pb(2)Te5Se octahedra, and edges with eight equivalent Pb(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Pb site, Pb(2) is bonded to one Te(2), four equivalent Te(1), and one Se(1) atom to form PbTe5Se octahedra that share  a cornercorner with one Pb(1)Te6 octahedra, corners with five equivalent Pb(2)Te5Se octahedra, edges with four equivalent Pb(3)Te2Se4 octahedra, edges with four equivalent Pb(2)Te5Se octahedra, and edges with four equivalent Pb(1)Te6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the third Pb site, Pb(3) is bonded to two equivalent Te(1) and four equivalent Se(1) atoms to form PbTe2Se4 octahedra that share corners with two equivalent Pb(1)Te6 octahedra, corners with four equivalent Pb(3)Te2Se4 octahedra, edges with four equivalent Pb(3)Te2Se4 octahedra, and edges with eight equivalent Pb(2)Te5Se octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Te sites. In the first Te site, Te(1) is bonded to one Pb(1), one Pb(3), and four equivalent Pb(2) atoms to form TePb6 octahedra that share  a cornercorner with one Te(2)Pb6 octahedra, corners with five equivalent Te(1)Pb6 octahedra, edges with four equivalent Te(1)Pb6 octahedra, edges with four equivalent Te(2)Pb6 octahedra, and edges with four equivalent Se(1)Pb6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Te site, Te(2) is bonded to one Pb(2) and five equivalent Pb(1) atoms to form TePb6 octahedra that share  a cornercorner with one Te(1)Pb6 octahedra,  a cornercorner with one Se(1)Pb6 octahedra, corners with four equivalent Te(2)Pb6 octahedra, edges with four equivalent Te(1)Pb6 octahedra, and edges with eight equivalent Te(2)Pb6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. Se(1) is bonded to two equivalent Pb(2) and four equivalent Pb(3) atoms to form SePb6 octahedra that share corners with two equivalent Te(2)Pb6 octahedra, corners with four equivalent Se(1)Pb6 octahedra, edges with four equivalent Se(1)Pb6 octahedra, and edges with eight equivalent Te(1)Pb6 octahedra. The corner-sharing octahedra are not tilted. is represented by the Crystallographic Information File (CIF) [CIF]
data_Te4Pb5Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   16.802
_cell_length_b   16.802
_cell_length_c   16.802
_cell_angle_alpha   164.309
_cell_angle_beta   164.309
_cell_angle_gamma   22.261
_symmetry_Int_Tables_number   1
_cell_volume   346.912
_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
  Te  Te0  1  0.900  0.900  0.000  1.0
  Te  Te1  1  0.301  0.301  0.000  1.0
  Te  Te2  1  0.699  0.699  0.000  1.0
  Te  Te3  1  0.100  0.100  0.000  1.0
  Pb  Pb4  1  0.200  0.200  0.000  1.0
  Pb  Pb5  1  0.402  0.402  0.000  1.0
  Pb  Pb6  1  0.800  0.800  0.000  1.0
  Pb  Pb7  1  0.598  0.598  0.000  1.0
  Pb  Pb8  1  0.000  0.000  0.000  1.0
  Se  Se9  1  0.500  0.500  0.000  1.0
[/CIF]
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