The structure described by Tm2Se3 crystallizes in the orthorhombic Fddd space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form a mixture of corner and edge-sharing TmSe6 octahedra. The corner-sharing octahedral tilt angles are 4°. In the second Tm site, Tm(2) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form a mixture of corner and edge-sharing TmSe6 octahedra. The corner-sharing octahedral tilt angles range from 3-4°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to two equivalent Tm(1) and two equivalent Tm(2) atoms. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to two equivalent Tm(1) and two equivalent Tm(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tm2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.963
_cell_length_b   6.963
_cell_length_c   12.709
_cell_angle_alpha   100.649
_cell_angle_beta   100.649
_cell_angle_gamma   108.982
_symmetry_Int_Tables_number   1
_cell_volume   552.424
_cell_formula_units_Z   4
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
  Tm  Tm0  1  0.709  0.959  0.918  1.0
  Tm  Tm1  1  0.541  0.791  0.582  1.0
  Tm  Tm2  1  0.291  0.041  0.082  1.0
  Tm  Tm3  1  0.459  0.209  0.418  1.0
  Tm  Tm4  1  0.372  0.622  0.245  1.0
  Tm  Tm5  1  0.878  0.128  0.255  1.0
  Tm  Tm6  1  0.628  0.377  0.755  1.0
  Tm  Tm7  1  0.123  0.872  0.745  1.0
  Se  Se8  1  0.867  0.117  0.750  1.0
  Se  Se9  1  0.383  0.633  0.750  1.0
  Se  Se10  1  0.133  0.883  0.250  1.0
  Se  Se11  1  0.617  0.367  0.250  1.0
  Se  Se12  1  0.548  0.804  0.088  1.0
  Se  Se13  1  0.696  0.952  0.412  1.0
  Se  Se14  1  0.216  0.461  0.412  1.0
  Se  Se15  1  0.039  0.284  0.088  1.0
  Se  Se16  1  0.452  0.196  0.912  1.0
  Se  Se17  1  0.304  0.048  0.588  1.0
  Se  Se18  1  0.784  0.539  0.588  1.0
  Se  Se19  1  0.961  0.716  0.912  1.0
[/CIF]
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The structure described by Tm2Se3 crystallizes in the orthorhombic Fddd space group. There are two inequivalent Tm sites. In the first Tm site, Tm(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form a mixture of corner and edge-sharing TmSe6 octahedra. The corner-sharing octahedral tilt angles are 4°. In the second Tm site, Tm(2) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form a mixture of corner and edge-sharing TmSe6 octahedra. The corner-sharing octahedral tilt angles range from 3-4°. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a rectangular see-saw-like geometry to two equivalent Tm(1) and two equivalent Tm(2) atoms. In the second Se site, Se(2) is bonded in a rectangular see-saw-like geometry to two equivalent Tm(1) and two equivalent Tm(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tm2Se3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.963
_cell_length_b   6.963
_cell_length_c   12.709
_cell_angle_alpha   100.649
_cell_angle_beta   100.649
_cell_angle_gamma   108.982
_symmetry_Int_Tables_number   1
_cell_volume   552.424
_cell_formula_units_Z   4
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
  Tm  Tm0  1  0.709  0.959  0.918  1.0
  Tm  Tm1  1  0.541  0.791  0.582  1.0
  Tm  Tm2  1  0.291  0.041  0.082  1.0
  Tm  Tm3  1  0.459  0.209  0.418  1.0
  Tm  Tm4  1  0.372  0.622  0.245  1.0
  Tm  Tm5  1  0.878  0.128  0.255  1.0
  Tm  Tm6  1  0.628  0.377  0.755  1.0
  Tm  Tm7  1  0.123  0.872  0.745  1.0
  Se  Se8  1  0.867  0.117  0.750  1.0
  Se  Se9  1  0.383  0.633  0.750  1.0
  Se  Se10  1  0.133  0.883  0.250  1.0
  Se  Se11  1  0.617  0.367  0.250  1.0
  Se  Se12  1  0.548  0.804  0.088  1.0
  Se  Se13  1  0.696  0.952  0.412  1.0
  Se  Se14  1  0.216  0.461  0.412  1.0
  Se  Se15  1  0.039  0.284  0.088  1.0
  Se  Se16  1  0.452  0.196  0.912  1.0
  Se  Se17  1  0.304  0.048  0.588  1.0
  Se  Se18  1  0.784  0.539  0.588  1.0
  Se  Se19  1  0.961  0.716  0.912  1.0
[/CIF]
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