The material described by Sm2AsSe is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent As(1) and four equivalent Se(1) atoms to form SmAs2Se4 octahedra that share corners with six equivalent Sm(1)As2Se4 octahedra, edges with four equivalent Sm(1)As2Se4 octahedra, and edges with eight equivalent Sm(2)As4Se2 octahedra. The corner-sharing octahedra are not tilted. In the second Sm site, Sm(2) is bonded to four equivalent As(1) and two equivalent Se(1) atoms to form SmAs4Se2 octahedra that share corners with six equivalent Sm(2)As4Se2 octahedra, edges with four equivalent Sm(2)As4Se2 octahedra, and edges with eight equivalent Sm(1)As2Se4 octahedra. The corner-sharing octahedra are not tilted. As(1) is bonded to two equivalent Sm(1) and four equivalent Sm(2) atoms to form AsSm6 octahedra that share corners with six equivalent As(1)Sm6 octahedra, edges with four equivalent As(1)Sm6 octahedra, and edges with eight equivalent Se(1)Sm6 octahedra. The corner-sharing octahedra are not tilted. Se(1) is bonded to two equivalent Sm(2) and four equivalent Sm(1) atoms to form SeSm6 octahedra that share corners with six equivalent Se(1)Sm6 octahedra, edges with four equivalent Se(1)Sm6 octahedra, and edges with eight equivalent As(1)Sm6 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_Sm2AsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.184
_cell_length_b   4.184
_cell_length_c   5.912
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   103.477
_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  0.000  0.000  0.500  1.0
  Sm  Sm1  1  0.500  0.500  0.000  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 material described by Sm2AsSe is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent As(1) and four equivalent Se(1) atoms to form SmAs2Se4 octahedra that share corners with six equivalent Sm(1)As2Se4 octahedra, edges with four equivalent Sm(1)As2Se4 octahedra, and edges with eight equivalent Sm(2)As4Se2 octahedra. The corner-sharing octahedra are not tilted. In the second Sm site, Sm(2) is bonded to four equivalent As(1) and two equivalent Se(1) atoms to form SmAs4Se2 octahedra that share corners with six equivalent Sm(2)As4Se2 octahedra, edges with four equivalent Sm(2)As4Se2 octahedra, and edges with eight equivalent Sm(1)As2Se4 octahedra. The corner-sharing octahedra are not tilted. As(1) is bonded to two equivalent Sm(1) and four equivalent Sm(2) atoms to form AsSm6 octahedra that share corners with six equivalent As(1)Sm6 octahedra, edges with four equivalent As(1)Sm6 octahedra, and edges with eight equivalent Se(1)Sm6 octahedra. The corner-sharing octahedra are not tilted. Se(1) is bonded to two equivalent Sm(2) and four equivalent Sm(1) atoms to form SeSm6 octahedra that share corners with six equivalent Se(1)Sm6 octahedra, edges with four equivalent Se(1)Sm6 octahedra, and edges with eight equivalent As(1)Sm6 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_Sm2AsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.184
_cell_length_b   4.184
_cell_length_c   5.912
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   103.477
_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  0.000  0.000  0.500  1.0
  Sm  Sm1  1  0.500  0.500  0.000  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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