The structure described by PbSn2Se3 is Caswellsilverite-like structured and crystallizes in the trigonal P-3m1 space group. Pb(1) is bonded to six equivalent Se(1) atoms to form PbSe6 octahedra that share corners with six equivalent Sn(1)Se6 octahedra, edges with six equivalent Pb(1)Se6 octahedra, and edges with six equivalent Sn(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 2°. Sn(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form SnSe6 octahedra that share corners with three equivalent Pb(1)Se6 octahedra, corners with three equivalent Sn(1)Se6 octahedra, edges with three equivalent Pb(1)Se6 octahedra, and edges with nine equivalent Sn(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Pb(1) and three equivalent Sn(1) atoms to form SeSn3Pb3 octahedra that share corners with three equivalent Se(1)Sn3Pb3 octahedra, corners with three equivalent Se(2)Sn6 octahedra, edges with three equivalent Se(2)Sn6 octahedra, and edges with nine equivalent Se(1)Sn3Pb3 octahedra. The corner-sharing octahedra are not tilted. In the second Se site, Se(2) is bonded to six equivalent Sn(1) atoms to form SeSn6 octahedra that share corners with six equivalent Se(1)Sn3Pb3 octahedra, edges with six equivalent Se(1)Sn3Pb3 octahedra, and edges with six equivalent Se(2)Sn6 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_Sn2PbSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.296
_cell_length_b   4.296
_cell_length_c   10.527
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   168.292
_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
  Sn  Sn0  1  0.333  0.667  0.664  1.0
  Sn  Sn1  1  0.667  0.333  0.336  1.0
  Pb  Pb2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.333  0.667  0.173  1.0
  Se  Se4  1  0.667  0.333  0.827  1.0
  Se  Se5  1  0.000  0.000  0.500  1.0
[/CIF]
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The structure described by PbSn2Se3 is Caswellsilverite-like structured and crystallizes in the trigonal P-3m1 space group. Pb(1) is bonded to six equivalent Se(1) atoms to form PbSe6 octahedra that share corners with six equivalent Sn(1)Se6 octahedra, edges with six equivalent Pb(1)Se6 octahedra, and edges with six equivalent Sn(1)Se6 octahedra. The corner-sharing octahedral tilt angles are 2°. Sn(1) is bonded to three equivalent Se(1) and three equivalent Se(2) atoms to form SnSe6 octahedra that share corners with three equivalent Pb(1)Se6 octahedra, corners with three equivalent Sn(1)Se6 octahedra, edges with three equivalent Pb(1)Se6 octahedra, and edges with nine equivalent Sn(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Pb(1) and three equivalent Sn(1) atoms to form SeSn3Pb3 octahedra that share corners with three equivalent Se(1)Sn3Pb3 octahedra, corners with three equivalent Se(2)Sn6 octahedra, edges with three equivalent Se(2)Sn6 octahedra, and edges with nine equivalent Se(1)Sn3Pb3 octahedra. The corner-sharing octahedra are not tilted. In the second Se site, Se(2) is bonded to six equivalent Sn(1) atoms to form SeSn6 octahedra that share corners with six equivalent Se(1)Sn3Pb3 octahedra, edges with six equivalent Se(1)Sn3Pb3 octahedra, and edges with six equivalent Se(2)Sn6 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_Sn2PbSe3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.296
_cell_length_b   4.296
_cell_length_c   10.527
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   168.292
_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
  Sn  Sn0  1  0.333  0.667  0.664  1.0
  Sn  Sn1  1  0.667  0.333  0.336  1.0
  Pb  Pb2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.333  0.667  0.173  1.0
  Se  Se4  1  0.667  0.333  0.827  1.0
  Se  Se5  1  0.000  0.000  0.500  1.0
[/CIF]
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