The material structure described by Sm2AsSe is Caswellsilverite-like structured and crystallizes in the tetragonal I4_1/amd space group. There are four inequivalent Sm sites. In the first Sm site, 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 octahedral tilt angles range from 0-3°. In the second Sm site, 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 octahedral tilt angles range from 0-3°. In the third Sm site, 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 octahedral tilt angles range from 0-3°. In the fourth Sm site, 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 octahedral tilt angles range from 0-3°. As(1) is bonded to six Sm(1,1,1) atoms to form AsSm6 octahedra that share corners with two equivalent Se(1)Sm6 octahedra, corners with four 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 octahedral tilt angles range from 0-3°. Se(1) is bonded to six Sm(1,1,1) atoms to form SeSm6 octahedra that share corners with two equivalent As(1)Sm6 octahedra, corners with four 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 octahedral tilt angles range from 0-3°. is represented by the CIF card [CIF]
data_Sm2AsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.261
_cell_length_b   7.261
_cell_length_c   7.261
_cell_angle_alpha   131.922
_cell_angle_beta   131.922
_cell_angle_gamma   70.353
_symmetry_Int_Tables_number   1
_cell_volume   207.692
_cell_formula_units_Z   2
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  0.744  0.744  0.000  1.0
  Sm  Sm1  1  0.494  0.994  0.500  1.0
  Sm  Sm2  1  0.256  0.256  0.000  1.0
  Sm  Sm3  1  0.006  0.506  0.500  1.0
  As  As4  1  0.500  0.500  0.000  1.0
  As  As5  1  0.250  0.750  0.500  1.0
  Se  Se6  1  0.000  0.000  0.000  1.0
  Se  Se7  1  0.750  0.250  0.500  1.0
[/CIF]
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The material structure described by Sm2AsSe is Caswellsilverite-like structured and crystallizes in the tetragonal I4_1/amd space group. There are four inequivalent Sm sites. In the first Sm site, 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 octahedral tilt angles range from 0-3°. In the second Sm site, 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 octahedral tilt angles range from 0-3°. In the third Sm site, 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 octahedral tilt angles range from 0-3°. In the fourth Sm site, 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 octahedral tilt angles range from 0-3°. As(1) is bonded to six Sm(1,1,1) atoms to form AsSm6 octahedra that share corners with two equivalent Se(1)Sm6 octahedra, corners with four 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 octahedral tilt angles range from 0-3°. Se(1) is bonded to six Sm(1,1,1) atoms to form SeSm6 octahedra that share corners with two equivalent As(1)Sm6 octahedra, corners with four 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 octahedral tilt angles range from 0-3°. is represented by the CIF card [CIF]
data_Sm2AsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.261
_cell_length_b   7.261
_cell_length_c   7.261
_cell_angle_alpha   131.922
_cell_angle_beta   131.922
_cell_angle_gamma   70.353
_symmetry_Int_Tables_number   1
_cell_volume   207.692
_cell_formula_units_Z   2
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  0.744  0.744  0.000  1.0
  Sm  Sm1  1  0.494  0.994  0.500  1.0
  Sm  Sm2  1  0.256  0.256  0.000  1.0
  Sm  Sm3  1  0.006  0.506  0.500  1.0
  As  As4  1  0.500  0.500  0.000  1.0
  As  As5  1  0.250  0.750  0.500  1.0
  Se  Se6  1  0.000  0.000  0.000  1.0
  Se  Se7  1  0.750  0.250  0.500  1.0
[/CIF]
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