The compound described by Sm2AsSe is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. Sm(1) is bonded to three equivalent As(1) and three equivalent Se(1) atoms to form a mixture of corner and edge-sharing SmAs3Se3 octahedra. The corner-sharing octahedra are not tilted. As(1) is bonded to six equivalent Sm(1) atoms to form AsSm6 octahedra that share corners with six equivalent Se(1)Sm6 octahedra, edges with six equivalent As(1)Sm6 octahedra, and edges with six equivalent Se(1)Sm6 octahedra. The corner-sharing octahedral tilt angles are 2°. Se(1) is bonded to six equivalent Sm(1) atoms to form SeSm6 octahedra that share corners with six equivalent As(1)Sm6 octahedra, edges with six equivalent As(1)Sm6 octahedra, and edges with six equivalent Se(1)Sm6 octahedra. The corner-sharing octahedral tilt angles are 2°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm2AsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.270
_cell_length_b   7.270
_cell_length_c   7.270
_cell_angle_alpha   33.471
_cell_angle_beta   33.471
_cell_angle_gamma   33.471
_symmetry_Int_Tables_number   1
_cell_volume   104.083
_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
  Sm  Sm0  1  0.254  0.254  0.254  1.0
  Sm  Sm1  1  0.746  0.746  0.746  1.0
  As  As2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.500  0.500  0.500  1.0
[/CIF]
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The compound described by Sm2AsSe is Caswellsilverite structured and crystallizes in the trigonal R-3m space group. Sm(1) is bonded to three equivalent As(1) and three equivalent Se(1) atoms to form a mixture of corner and edge-sharing SmAs3Se3 octahedra. The corner-sharing octahedra are not tilted. As(1) is bonded to six equivalent Sm(1) atoms to form AsSm6 octahedra that share corners with six equivalent Se(1)Sm6 octahedra, edges with six equivalent As(1)Sm6 octahedra, and edges with six equivalent Se(1)Sm6 octahedra. The corner-sharing octahedral tilt angles are 2°. Se(1) is bonded to six equivalent Sm(1) atoms to form SeSm6 octahedra that share corners with six equivalent As(1)Sm6 octahedra, edges with six equivalent As(1)Sm6 octahedra, and edges with six equivalent Se(1)Sm6 octahedra. The corner-sharing octahedral tilt angles are 2°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sm2AsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.270
_cell_length_b   7.270
_cell_length_c   7.270
_cell_angle_alpha   33.471
_cell_angle_beta   33.471
_cell_angle_gamma   33.471
_symmetry_Int_Tables_number   1
_cell_volume   104.083
_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
  Sm  Sm0  1  0.254  0.254  0.254  1.0
  Sm  Sm1  1  0.746  0.746  0.746  1.0
  As  As2  1  0.000  0.000  0.000  1.0
  Se  Se3  1  0.500  0.500  0.500  1.0
[/CIF]
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