The structure described by SmSe2 crystallizes in the tetragonal P4/nmm space group. Sm(1) is bonded in a 9-coordinate geometry to four equivalent Se(1) and five equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 8-coordinate geometry to four equivalent Sm(1) and four equivalent Se(1) atoms. In the second Se site, Se(2) is bonded to five equivalent Sm(1) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. is represented by the CIF file [CIF]
data_SmSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.117
_cell_length_b   4.117
_cell_length_c   8.485
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   143.805
_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  0.750  0.750  0.726  1.0
  Sm  Sm1  1  0.250  0.250  0.274  1.0
  Se  Se2  1  0.750  0.250  0.000  1.0
  Se  Se3  1  0.250  0.750  0.000  1.0
  Se  Se4  1  0.750  0.750  0.368  1.0
  Se  Se5  1  0.250  0.250  0.632  1.0
[/CIF]
.
The structure described by SmSe2 crystallizes in the tetragonal P4/nmm space group. Sm(1) is bonded in a 9-coordinate geometry to four equivalent Se(1) and five equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 8-coordinate geometry to four equivalent Sm(1) and four equivalent Se(1) atoms. In the second Se site, Se(2) is bonded to five equivalent Sm(1) atoms to form a mixture of distorted corner and edge-sharing SeSm5 trigonal bipyramids. is represented by the CIF file [CIF]
data_SmSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.117
_cell_length_b   4.117
_cell_length_c   8.485
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   143.805
_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  0.750  0.750  0.726  1.0
  Sm  Sm1  1  0.250  0.250  0.274  1.0
  Se  Se2  1  0.750  0.250  0.000  1.0
  Se  Se3  1  0.250  0.750  0.000  1.0
  Se  Se4  1  0.750  0.750  0.368  1.0
  Se  Se5  1  0.250  0.250  0.632  1.0
[/CIF]
.