The material described by NaSm2Se3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/c space group. Na(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form NaSe6 octahedra that share corners with two equivalent Na(1)Se6 octahedra, corners with two equivalent Sm(1)Se6 octahedra, corners with two equivalent Sm(2)Se6 octahedra, edges with two equivalent Na(1)Se6 octahedra, edges with five equivalent Sm(1)Se6 octahedra, and edges with five equivalent Sm(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form SmSe6 octahedra that share corners with two equivalent Na(1)Se6 octahedra, corners with two equivalent Sm(1)Se6 octahedra, corners with two equivalent Sm(2)Se6 octahedra, edges with two equivalent Sm(1)Se6 octahedra, edges with five equivalent Na(1)Se6 octahedra, and edges with five equivalent Sm(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Sm site, Sm(2) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form SmSe6 octahedra that share corners with two equivalent Na(1)Se6 octahedra, corners with two equivalent Sm(1)Se6 octahedra, corners with two equivalent Sm(2)Se6 octahedra, edges with two equivalent Sm(2)Se6 octahedra, edges with five equivalent Na(1)Se6 octahedra, and edges with five equivalent Sm(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Na(1), two equivalent Sm(1), and two equivalent Sm(2) atoms to form a mixture of corner and edge-sharing SeNa2Sm4 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Se site, Se(2) is bonded to two equivalent Na(1), two equivalent Sm(1), and two equivalent Sm(2) atoms to form a mixture of corner and edge-sharing SeNa2Sm4 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. is represented by the CIF file [CIF]
data_NaSm2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.221
_cell_length_b   7.221
_cell_length_c   7.203
_cell_angle_alpha   80.289
_cell_angle_beta   80.289
_cell_angle_gamma   119.550
_symmetry_Int_Tables_number   1
_cell_volume   307.829
_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
  Na  Na0  1  0.418  0.582  0.750  1.0
  Na  Na1  1  0.582  0.418  0.250  1.0
  Sm  Sm2  1  0.749  0.251  0.750  1.0
  Sm  Sm3  1  0.083  0.917  0.750  1.0
  Sm  Sm4  1  0.917  0.083  0.250  1.0
  Sm  Sm5  1  0.251  0.749  0.250  1.0
  Se  Se6  1  0.164  0.331  0.502  1.0
  Se  Se7  1  0.836  0.669  0.498  1.0
  Se  Se8  1  0.669  0.836  0.998  1.0
  Se  Se9  1  0.500  0.000  0.500  1.0
  Se  Se10  1  0.331  0.164  0.002  1.0
  Se  Se11  1  0.000  0.500  0.000  1.0
[/CIF]
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The material described by NaSm2Se3 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/c space group. Na(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form NaSe6 octahedra that share corners with two equivalent Na(1)Se6 octahedra, corners with two equivalent Sm(1)Se6 octahedra, corners with two equivalent Sm(2)Se6 octahedra, edges with two equivalent Na(1)Se6 octahedra, edges with five equivalent Sm(1)Se6 octahedra, and edges with five equivalent Sm(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form SmSe6 octahedra that share corners with two equivalent Na(1)Se6 octahedra, corners with two equivalent Sm(1)Se6 octahedra, corners with two equivalent Sm(2)Se6 octahedra, edges with two equivalent Sm(1)Se6 octahedra, edges with five equivalent Na(1)Se6 octahedra, and edges with five equivalent Sm(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Sm site, Sm(2) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form SmSe6 octahedra that share corners with two equivalent Na(1)Se6 octahedra, corners with two equivalent Sm(1)Se6 octahedra, corners with two equivalent Sm(2)Se6 octahedra, edges with two equivalent Sm(2)Se6 octahedra, edges with five equivalent Na(1)Se6 octahedra, and edges with five equivalent Sm(1)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Na(1), two equivalent Sm(1), and two equivalent Sm(2) atoms to form a mixture of corner and edge-sharing SeNa2Sm4 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. In the second Se site, Se(2) is bonded to two equivalent Na(1), two equivalent Sm(1), and two equivalent Sm(2) atoms to form a mixture of corner and edge-sharing SeNa2Sm4 octahedra. The corner-sharing octahedral tilt angles range from 0-1°. is represented by the CIF file [CIF]
data_NaSm2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.221
_cell_length_b   7.221
_cell_length_c   7.203
_cell_angle_alpha   80.289
_cell_angle_beta   80.289
_cell_angle_gamma   119.550
_symmetry_Int_Tables_number   1
_cell_volume   307.829
_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
  Na  Na0  1  0.418  0.582  0.750  1.0
  Na  Na1  1  0.582  0.418  0.250  1.0
  Sm  Sm2  1  0.749  0.251  0.750  1.0
  Sm  Sm3  1  0.083  0.917  0.750  1.0
  Sm  Sm4  1  0.917  0.083  0.250  1.0
  Sm  Sm5  1  0.251  0.749  0.250  1.0
  Se  Se6  1  0.164  0.331  0.502  1.0
  Se  Se7  1  0.836  0.669  0.498  1.0
  Se  Se8  1  0.669  0.836  0.998  1.0
  Se  Se9  1  0.500  0.000  0.500  1.0
  Se  Se10  1  0.331  0.164  0.002  1.0
  Se  Se11  1  0.000  0.500  0.000  1.0
[/CIF]
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