The structure described by Tm2O3 crystallizes in the monoclinic C2/m space group. There are three inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(3), and three equivalent O(2) atoms. In the second Tm site, Tm(2) is bonded in a 7-coordinate geometry to one O(2), one O(5), two equivalent O(1), and three equivalent O(4) atoms. In the third Tm site, Tm(3) is bonded to one O(1), one O(4), two equivalent O(3), and two equivalent O(5) atoms to form a mixture of distorted corner and edge-sharing TmO6 octahedra. The corner-sharing octahedra are not tilted. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Tm(3), two equivalent Tm(1), and two equivalent Tm(2) atoms to form distorted OTm5 square pyramids that share corners with two equivalent O(3)Tm4 tetrahedra, corners with five equivalent O(4)Tm4 tetrahedra, corners with two equivalent O(2)Tm4 trigonal pyramids, edges with two equivalent O(5)Tm6 octahedra, edges with two equivalent O(1)Tm5 square pyramids,  an edgeedge with one O(4)Tm4 tetrahedra, edges with two equivalent O(3)Tm4 tetrahedra, and edges with three equivalent O(2)Tm4 trigonal pyramids. In the second O site, O(2) is bonded to one Tm(2) and three equivalent Tm(1) atoms to form distorted OTm4 trigonal pyramids that share  a cornercorner with one O(5)Tm6 octahedra, corners with two equivalent O(1)Tm5 square pyramids, corners with three equivalent O(4)Tm4 tetrahedra, corners with six equivalent O(3)Tm4 tetrahedra, corners with two equivalent O(2)Tm4 trigonal pyramids, edges with three equivalent O(1)Tm5 square pyramids, and edges with two equivalent O(2)Tm4 trigonal pyramids. The corner-sharing octahedral tilt angles are 37°. In the third O site, O(3) is bonded to two equivalent Tm(1) and two equivalent Tm(3) atoms to form OTm4 tetrahedra that share corners with two equivalent O(5)Tm6 octahedra, corners with two equivalent O(1)Tm5 square pyramids, corners with two equivalent O(3)Tm4 tetrahedra, corners with two equivalent O(4)Tm4 tetrahedra, corners with six equivalent O(2)Tm4 trigonal pyramids,  an edgeedge with one O(5)Tm6 octahedra, edges with two equivalent O(1)Tm5 square pyramids, and  an edgeedge with one O(3)Tm4 tetrahedra. The corner-sharing octahedral tilt angles are 13°. In the fourth O site, O(4) is bonded to one Tm(3) and three equivalent Tm(2) atoms to form OTm4 tetrahedra that share  a cornercorner with one O(5)Tm6 octahedra, corners with five equivalent O(1)Tm5 square pyramids, corners with two equivalent O(3)Tm4 tetrahedra, corners with two equivalent O(4)Tm4 tetrahedra, corners with three equivalent O(2)Tm4 trigonal pyramids, edges with two equivalent O(5)Tm6 octahedra,  an edgeedge with one O(1)Tm5 square pyramid, and edges with two equivalent O(4)Tm4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. In the fifth O site, O(5) is bonded to two equivalent Tm(2) and four equivalent Tm(3) atoms to form OTm6 octahedra that share corners with two equivalent O(4)Tm4 tetrahedra, corners with four equivalent O(3)Tm4 tetrahedra, corners with two equivalent O(2)Tm4 trigonal pyramids, edges with two equivalent O(5)Tm6 octahedra, edges with four equivalent O(1)Tm5 square pyramids, edges with two equivalent O(3)Tm4 tetrahedra, and edges with four equivalent O(4)Tm4 tetrahedra. is represented by the CIF card [CIF]
data_Tm2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.405
_cell_length_b   7.066
_cell_length_c   8.430
_cell_angle_alpha   99.903
_cell_angle_beta   90.000
_cell_angle_gamma   103.940
_symmetry_Int_Tables_number   1
_cell_volume   193.711
_cell_formula_units_Z   3
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  0.635  0.270  0.487  1.0
  Tm  Tm1  1  0.691  0.382  0.137  1.0
  Tm  Tm2  1  0.309  0.618  0.863  1.0
  Tm  Tm3  1  0.033  0.065  0.814  1.0
  Tm  Tm4  1  0.365  0.730  0.513  1.0
  Tm  Tm5  1  0.967  0.935  0.186  1.0
  O  O6  1  0.127  0.255  0.281  1.0
  O  O7  1  0.207  0.414  0.623  1.0
  O  O8  1  0.530  0.059  0.657  1.0
  O  O9  1  0.873  0.745  0.719  1.0
  O  O10  1  0.826  0.651  0.031  1.0
  O  O11  1  0.500  0.000  0.000  1.0
  O  O12  1  0.174  0.349  0.969  1.0
  O  O13  1  0.793  0.586  0.377  1.0
  O  O14  1  0.470  0.941  0.343  1.0
[/CIF]
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The structure described by Tm2O3 crystallizes in the monoclinic C2/m space group. There are three inequivalent Tm sites. In the first Tm site, Tm(1) is bonded in a 7-coordinate geometry to two equivalent O(1), two equivalent O(3), and three equivalent O(2) atoms. In the second Tm site, Tm(2) is bonded in a 7-coordinate geometry to one O(2), one O(5), two equivalent O(1), and three equivalent O(4) atoms. In the third Tm site, Tm(3) is bonded to one O(1), one O(4), two equivalent O(3), and two equivalent O(5) atoms to form a mixture of distorted corner and edge-sharing TmO6 octahedra. The corner-sharing octahedra are not tilted. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Tm(3), two equivalent Tm(1), and two equivalent Tm(2) atoms to form distorted OTm5 square pyramids that share corners with two equivalent O(3)Tm4 tetrahedra, corners with five equivalent O(4)Tm4 tetrahedra, corners with two equivalent O(2)Tm4 trigonal pyramids, edges with two equivalent O(5)Tm6 octahedra, edges with two equivalent O(1)Tm5 square pyramids,  an edgeedge with one O(4)Tm4 tetrahedra, edges with two equivalent O(3)Tm4 tetrahedra, and edges with three equivalent O(2)Tm4 trigonal pyramids. In the second O site, O(2) is bonded to one Tm(2) and three equivalent Tm(1) atoms to form distorted OTm4 trigonal pyramids that share  a cornercorner with one O(5)Tm6 octahedra, corners with two equivalent O(1)Tm5 square pyramids, corners with three equivalent O(4)Tm4 tetrahedra, corners with six equivalent O(3)Tm4 tetrahedra, corners with two equivalent O(2)Tm4 trigonal pyramids, edges with three equivalent O(1)Tm5 square pyramids, and edges with two equivalent O(2)Tm4 trigonal pyramids. The corner-sharing octahedral tilt angles are 37°. In the third O site, O(3) is bonded to two equivalent Tm(1) and two equivalent Tm(3) atoms to form OTm4 tetrahedra that share corners with two equivalent O(5)Tm6 octahedra, corners with two equivalent O(1)Tm5 square pyramids, corners with two equivalent O(3)Tm4 tetrahedra, corners with two equivalent O(4)Tm4 tetrahedra, corners with six equivalent O(2)Tm4 trigonal pyramids,  an edgeedge with one O(5)Tm6 octahedra, edges with two equivalent O(1)Tm5 square pyramids, and  an edgeedge with one O(3)Tm4 tetrahedra. The corner-sharing octahedral tilt angles are 13°. In the fourth O site, O(4) is bonded to one Tm(3) and three equivalent Tm(2) atoms to form OTm4 tetrahedra that share  a cornercorner with one O(5)Tm6 octahedra, corners with five equivalent O(1)Tm5 square pyramids, corners with two equivalent O(3)Tm4 tetrahedra, corners with two equivalent O(4)Tm4 tetrahedra, corners with three equivalent O(2)Tm4 trigonal pyramids, edges with two equivalent O(5)Tm6 octahedra,  an edgeedge with one O(1)Tm5 square pyramid, and edges with two equivalent O(4)Tm4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. In the fifth O site, O(5) is bonded to two equivalent Tm(2) and four equivalent Tm(3) atoms to form OTm6 octahedra that share corners with two equivalent O(4)Tm4 tetrahedra, corners with four equivalent O(3)Tm4 tetrahedra, corners with two equivalent O(2)Tm4 trigonal pyramids, edges with two equivalent O(5)Tm6 octahedra, edges with four equivalent O(1)Tm5 square pyramids, edges with two equivalent O(3)Tm4 tetrahedra, and edges with four equivalent O(4)Tm4 tetrahedra. is represented by the CIF card [CIF]
data_Tm2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.405
_cell_length_b   7.066
_cell_length_c   8.430
_cell_angle_alpha   99.903
_cell_angle_beta   90.000
_cell_angle_gamma   103.940
_symmetry_Int_Tables_number   1
_cell_volume   193.711
_cell_formula_units_Z   3
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  0.635  0.270  0.487  1.0
  Tm  Tm1  1  0.691  0.382  0.137  1.0
  Tm  Tm2  1  0.309  0.618  0.863  1.0
  Tm  Tm3  1  0.033  0.065  0.814  1.0
  Tm  Tm4  1  0.365  0.730  0.513  1.0
  Tm  Tm5  1  0.967  0.935  0.186  1.0
  O  O6  1  0.127  0.255  0.281  1.0
  O  O7  1  0.207  0.414  0.623  1.0
  O  O8  1  0.530  0.059  0.657  1.0
  O  O9  1  0.873  0.745  0.719  1.0
  O  O10  1  0.826  0.651  0.031  1.0
  O  O11  1  0.500  0.000  0.000  1.0
  O  O12  1  0.174  0.349  0.969  1.0
  O  O13  1  0.793  0.586  0.377  1.0
  O  O14  1  0.470  0.941  0.343  1.0
[/CIF]
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