The material described by Yb(TmSe2)2 crystallizes in the monoclinic P2/m space group. Yb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form YbSe6 octahedra that share corners with six equivalent Tm(1)Se6 octahedra, edges with two equivalent Yb(1)Se6 octahedra, edges with two equivalent Tm(1)Se6 octahedra, and edges with four equivalent Tm(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 2-4°. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form TmSe6 octahedra that share corners with six equivalent Yb(1)Se6 octahedra, edges with two equivalent Yb(1)Se6 octahedra, edges with two equivalent Tm(1)Se6 octahedra, and edges with four equivalent Tm(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 2-4°. In the second Tm site, Tm(2) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form TmSe6 octahedra that share edges with two equivalent Tm(2)Se6 octahedra, edges with four equivalent Yb(1)Se6 octahedra, and edges with four equivalent Tm(1)Se6 octahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Yb(1), one Tm(2), and two equivalent Tm(1) atoms to form a mixture of corner and edge-sharing SeYb2Tm3 square pyramids. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to one Yb(1), one Tm(1), and two equivalent Tm(2) atoms. is represented by the CIF file [CIF]
data_Yb(TmSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.059
_cell_length_b   6.923
_cell_length_c   7.076
_cell_angle_alpha   71.895
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   189.025
_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
  Yb  Yb0  1  0.000  0.500  0.500  1.0
  Tm  Tm1  1  0.000  0.000  0.000  1.0
  Tm  Tm2  1  0.500  0.500  0.000  1.0
  Se  Se3  1  0.500  0.758  0.243  1.0
  Se  Se4  1  0.000  0.258  0.233  1.0
  Se  Se5  1  0.500  0.242  0.757  1.0
  Se  Se6  1  0.000  0.742  0.767  1.0
[/CIF]
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The material described by Yb(TmSe2)2 crystallizes in the monoclinic P2/m space group. Yb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form YbSe6 octahedra that share corners with six equivalent Tm(1)Se6 octahedra, edges with two equivalent Yb(1)Se6 octahedra, edges with two equivalent Tm(1)Se6 octahedra, and edges with four equivalent Tm(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 2-4°. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form TmSe6 octahedra that share corners with six equivalent Yb(1)Se6 octahedra, edges with two equivalent Yb(1)Se6 octahedra, edges with two equivalent Tm(1)Se6 octahedra, and edges with four equivalent Tm(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 2-4°. In the second Tm site, Tm(2) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form TmSe6 octahedra that share edges with two equivalent Tm(2)Se6 octahedra, edges with four equivalent Yb(1)Se6 octahedra, and edges with four equivalent Tm(1)Se6 octahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Yb(1), one Tm(2), and two equivalent Tm(1) atoms to form a mixture of corner and edge-sharing SeYb2Tm3 square pyramids. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to one Yb(1), one Tm(1), and two equivalent Tm(2) atoms. is represented by the CIF file [CIF]
data_Yb(TmSe2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.059
_cell_length_b   6.923
_cell_length_c   7.076
_cell_angle_alpha   71.895
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   189.025
_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
  Yb  Yb0  1  0.000  0.500  0.500  1.0
  Tm  Tm1  1  0.000  0.000  0.000  1.0
  Tm  Tm2  1  0.500  0.500  0.000  1.0
  Se  Se3  1  0.500  0.758  0.243  1.0
  Se  Se4  1  0.000  0.258  0.233  1.0
  Se  Se5  1  0.500  0.242  0.757  1.0
  Se  Se6  1  0.000  0.742  0.767  1.0
[/CIF]
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