The material structure described by Tb2O3 crystallizes in the monoclinic C2/m space group. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing TbO6 octahedra. The corner-sharing octahedra are not tilted. In the second Tb site, Tb(2) is bonded in a 7-coordinate geometry to one O(1), one O(3), two equivalent O(5), and three equivalent O(4) atoms. In the third Tb site, Tb(3) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(5), and three equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Tb(2) and four equivalent Tb(1) atoms to form OTb6 octahedra that share corners with two equivalent O(4)Tb4 tetrahedra, corners with four equivalent O(2)Tb4 tetrahedra, edges with two equivalent O(1)Tb6 octahedra, edges with four equivalent O(5)Tb5 square pyramids, edges with two equivalent O(2)Tb4 tetrahedra, and edges with four equivalent O(4)Tb4 tetrahedra. In the second O site, O(2) is bonded to two equivalent Tb(1) and two equivalent Tb(3) atoms to form OTb4 tetrahedra that share corners with two equivalent O(1)Tb6 octahedra, corners with two equivalent O(5)Tb5 square pyramids, corners with two equivalent O(2)Tb4 tetrahedra, corners with two equivalent O(4)Tb4 tetrahedra,  an edgeedge with one O(1)Tb6 octahedra, edges with two equivalent O(5)Tb5 square pyramids, and  an edgeedge with one O(2)Tb4 tetrahedra. The corner-sharing octahedral tilt angles are 14°. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Tb(2) and three equivalent Tb(3) atoms. In the fourth O site, O(4) is bonded to one Tb(1) and three equivalent Tb(2) atoms to form OTb4 tetrahedra that share  a cornercorner with one O(1)Tb6 octahedra, corners with five equivalent O(5)Tb5 square pyramids, corners with two equivalent O(2)Tb4 tetrahedra, corners with two equivalent O(4)Tb4 tetrahedra, edges with two equivalent O(1)Tb6 octahedra,  an edgeedge with one O(5)Tb5 square pyramid, and edges with two equivalent O(4)Tb4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. In the fifth O site, O(5) is bonded to one Tb(1), two equivalent Tb(2), and two equivalent Tb(3) atoms to form distorted OTb5 square pyramids that share corners with two equivalent O(2)Tb4 tetrahedra, corners with five equivalent O(4)Tb4 tetrahedra, edges with two equivalent O(1)Tb6 octahedra, edges with two equivalent O(5)Tb5 square pyramids,  an edgeedge with one O(4)Tb4 tetrahedra, and edges with two equivalent O(2)Tb4 tetrahedra. is represented by the CIF file [CIF]
data_Tb2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.513
_cell_length_b   7.206
_cell_length_c   8.651
_cell_angle_alpha   99.753
_cell_angle_beta   90.000
_cell_angle_gamma   104.107
_symmetry_Int_Tables_number   1
_cell_volume   209.096
_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
  Tb  Tb0  1  0.033  0.067  0.812  1.0
  Tb  Tb1  1  0.967  0.933  0.188  1.0
  Tb  Tb2  1  0.309  0.618  0.862  1.0
  Tb  Tb3  1  0.691  0.382  0.138  1.0
  Tb  Tb4  1  0.365  0.730  0.512  1.0
  Tb  Tb5  1  0.635  0.270  0.488  1.0
  O  O6  1  0.500  0.000  0.000  1.0
  O  O7  1  0.528  0.057  0.656  1.0
  O  O8  1  0.472  0.943  0.344  1.0
  O  O9  1  0.205  0.410  0.624  1.0
  O  O10  1  0.795  0.590  0.376  1.0
  O  O11  1  0.175  0.350  0.971  1.0
  O  O12  1  0.128  0.256  0.283  1.0
  O  O13  1  0.872  0.744  0.717  1.0
  O  O14  1  0.825  0.650  0.029  1.0
[/CIF]
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The material structure described by Tb2O3 crystallizes in the monoclinic C2/m space group. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form a mixture of distorted corner and edge-sharing TbO6 octahedra. The corner-sharing octahedra are not tilted. In the second Tb site, Tb(2) is bonded in a 7-coordinate geometry to one O(1), one O(3), two equivalent O(5), and three equivalent O(4) atoms. In the third Tb site, Tb(3) is bonded in a 7-coordinate geometry to two equivalent O(2), two equivalent O(5), and three equivalent O(3) atoms. There are five inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Tb(2) and four equivalent Tb(1) atoms to form OTb6 octahedra that share corners with two equivalent O(4)Tb4 tetrahedra, corners with four equivalent O(2)Tb4 tetrahedra, edges with two equivalent O(1)Tb6 octahedra, edges with four equivalent O(5)Tb5 square pyramids, edges with two equivalent O(2)Tb4 tetrahedra, and edges with four equivalent O(4)Tb4 tetrahedra. In the second O site, O(2) is bonded to two equivalent Tb(1) and two equivalent Tb(3) atoms to form OTb4 tetrahedra that share corners with two equivalent O(1)Tb6 octahedra, corners with two equivalent O(5)Tb5 square pyramids, corners with two equivalent O(2)Tb4 tetrahedra, corners with two equivalent O(4)Tb4 tetrahedra,  an edgeedge with one O(1)Tb6 octahedra, edges with two equivalent O(5)Tb5 square pyramids, and  an edgeedge with one O(2)Tb4 tetrahedra. The corner-sharing octahedral tilt angles are 14°. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Tb(2) and three equivalent Tb(3) atoms. In the fourth O site, O(4) is bonded to one Tb(1) and three equivalent Tb(2) atoms to form OTb4 tetrahedra that share  a cornercorner with one O(1)Tb6 octahedra, corners with five equivalent O(5)Tb5 square pyramids, corners with two equivalent O(2)Tb4 tetrahedra, corners with two equivalent O(4)Tb4 tetrahedra, edges with two equivalent O(1)Tb6 octahedra,  an edgeedge with one O(5)Tb5 square pyramid, and edges with two equivalent O(4)Tb4 tetrahedra. The corner-sharing octahedral tilt angles are 50°. In the fifth O site, O(5) is bonded to one Tb(1), two equivalent Tb(2), and two equivalent Tb(3) atoms to form distorted OTb5 square pyramids that share corners with two equivalent O(2)Tb4 tetrahedra, corners with five equivalent O(4)Tb4 tetrahedra, edges with two equivalent O(1)Tb6 octahedra, edges with two equivalent O(5)Tb5 square pyramids,  an edgeedge with one O(4)Tb4 tetrahedra, and edges with two equivalent O(2)Tb4 tetrahedra. is represented by the CIF file [CIF]
data_Tb2O3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.513
_cell_length_b   7.206
_cell_length_c   8.651
_cell_angle_alpha   99.753
_cell_angle_beta   90.000
_cell_angle_gamma   104.107
_symmetry_Int_Tables_number   1
_cell_volume   209.096
_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
  Tb  Tb0  1  0.033  0.067  0.812  1.0
  Tb  Tb1  1  0.967  0.933  0.188  1.0
  Tb  Tb2  1  0.309  0.618  0.862  1.0
  Tb  Tb3  1  0.691  0.382  0.138  1.0
  Tb  Tb4  1  0.365  0.730  0.512  1.0
  Tb  Tb5  1  0.635  0.270  0.488  1.0
  O  O6  1  0.500  0.000  0.000  1.0
  O  O7  1  0.528  0.057  0.656  1.0
  O  O8  1  0.472  0.943  0.344  1.0
  O  O9  1  0.205  0.410  0.624  1.0
  O  O10  1  0.795  0.590  0.376  1.0
  O  O11  1  0.175  0.350  0.971  1.0
  O  O12  1  0.128  0.256  0.283  1.0
  O  O13  1  0.872  0.744  0.717  1.0
  O  O14  1  0.825  0.650  0.029  1.0
[/CIF]
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