The material described by Tb2TiO5 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to one O(3), one O(5), two equivalent O(1), and three equivalent O(2) atoms to form distorted TbO7 hexagonal pyramids that share corners with two equivalent Tb(2)O7 pentagonal bipyramids,  a cornercorner with one Ti(1)O5 trigonal bipyramid, edges with four equivalent Tb(1)O7 hexagonal pyramids, edges with three equivalent Tb(2)O7 pentagonal bipyramids, and edges with two equivalent Ti(1)O5 trigonal bipyramids. In the second Tb site, Tb(2) is bonded to one O(1), one O(2), one O(3), two equivalent O(4), and two equivalent O(5) atoms to form distorted TbO7 pentagonal bipyramids that share corners with two equivalent Tb(1)O7 hexagonal pyramids, corners with three equivalent Ti(1)O5 trigonal bipyramids, edges with three equivalent Tb(1)O7 hexagonal pyramids, edges with two equivalent Tb(2)O7 pentagonal bipyramids, and edges with two equivalent Ti(1)O5 trigonal bipyramids. Ti(1) is bonded to one O(1), one O(4), one O(5), and two equivalent O(3) atoms to form distorted TiO5 trigonal bipyramids that share  a cornercorner with one Tb(1)O7 hexagonal pyramid, corners with three equivalent Tb(2)O7 pentagonal bipyramids, corners with two equivalent Ti(1)O5 trigonal bipyramids, edges with two equivalent Tb(1)O7 hexagonal pyramids, and edges with two equivalent Tb(2)O7 pentagonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Tb(2), two equivalent Tb(1), and one Ti(1) atom to form OTb3Ti tetrahedra that share  a cornercorner with one O(3)Tb2Ti2 tetrahedra,  a cornercorner with one O(5)Tb3Ti tetrahedra, corners with two equivalent O(1)Tb3Ti tetrahedra, corners with five equivalent O(2)Tb4 tetrahedra,  an edgeedge with one O(2)Tb4 tetrahedra, edges with two equivalent O(3)Tb2Ti2 tetrahedra, and edges with two equivalent O(5)Tb3Ti tetrahedra. In the second O site, O(2) is bonded to one Tb(2) and three equivalent Tb(1) atoms to form OTb4 tetrahedra that share corners with two equivalent O(3)Tb2Ti2 tetrahedra, corners with two equivalent O(2)Tb4 tetrahedra, corners with five equivalent O(1)Tb3Ti tetrahedra, corners with five equivalent O(5)Tb3Ti tetrahedra,  an edgeedge with one O(3)Tb2Ti2 tetrahedra,  an edgeedge with one O(1)Tb3Ti tetrahedra, and edges with two equivalent O(2)Tb4 tetrahedra. In the third O site, O(3) is bonded to one Tb(1), one Tb(2), and two equivalent Ti(1) atoms to form distorted OTb2Ti2 tetrahedra that share  a cornercorner with one O(1)Tb3Ti tetrahedra,  a cornercorner with one O(5)Tb3Ti tetrahedra, corners with two equivalent O(3)Tb2Ti2 tetrahedra, corners with two equivalent O(2)Tb4 tetrahedra,  an edgeedge with one O(2)Tb4 tetrahedra, edges with two equivalent O(1)Tb3Ti tetrahedra, and edges with two equivalent O(5)Tb3Ti tetrahedra. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Tb(2) and one Ti(1) atom. In the fifth O site, O(5) is bonded to one Tb(1), two equivalent Tb(2), and one Ti(1) atom to form OTb3Ti tetrahedra that share  a cornercorner with one O(3)Tb2Ti2 tetrahedra,  a cornercorner with one O(1)Tb3Ti tetrahedra, corners with two equivalent O(5)Tb3Ti tetrahedra, corners with five equivalent O(2)Tb4 tetrahedra, edges with two equivalent O(3)Tb2Ti2 tetrahedra, and edges with two equivalent O(1)Tb3Ti tetrahedra. is represented by the CIF card [CIF]
data_Tb2TiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.701
_cell_length_b   10.389
_cell_length_c   11.278
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   433.671
_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
  Tb  Tb0  1  0.250  0.136  0.944  1.0
  Tb  Tb1  1  0.250  0.636  0.556  1.0
  Tb  Tb2  1  0.750  0.864  0.056  1.0
  Tb  Tb3  1  0.750  0.364  0.444  1.0
  Tb  Tb4  1  0.750  0.386  0.777  1.0
  Tb  Tb5  1  0.750  0.886  0.723  1.0
  Tb  Tb6  1  0.250  0.614  0.223  1.0
  Tb  Tb7  1  0.250  0.114  0.277  1.0
  Ti  Ti8  1  0.250  0.175  0.620  1.0
  Ti  Ti9  1  0.250  0.675  0.880  1.0
  Ti  Ti10  1  0.750  0.825  0.380  1.0
  Ti  Ti11  1  0.750  0.325  0.120  1.0
  O  O12  1  0.250  0.224  0.458  1.0
  O  O13  1  0.250  0.724  0.042  1.0
  O  O14  1  0.750  0.776  0.542  1.0
  O  O15  1  0.750  0.276  0.958  1.0
  O  O16  1  0.250  0.493  0.395  1.0
  O  O17  1  0.250  0.993  0.105  1.0
  O  O18  1  0.750  0.507  0.605  1.0
  O  O19  1  0.750  0.007  0.895  1.0
  O  O20  1  0.250  0.263  0.117  1.0
  O  O21  1  0.250  0.763  0.383  1.0
  O  O22  1  0.750  0.737  0.883  1.0
  O  O23  1  0.750  0.237  0.617  1.0
  O  O24  1  0.250  0.008  0.654  1.0
  O  O25  1  0.250  0.508  0.846  1.0
  O  O26  1  0.750  0.992  0.346  1.0
  O  O27  1  0.750  0.492  0.154  1.0
  O  O28  1  0.250  0.257  0.770  1.0
  O  O29  1  0.250  0.757  0.730  1.0
  O  O30  1  0.750  0.743  0.230  1.0
  O  O31  1  0.750  0.243  0.270  1.0
[/CIF]
.
The material described by Tb2TiO5 crystallizes in the orthorhombic Pnma space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to one O(3), one O(5), two equivalent O(1), and three equivalent O(2) atoms to form distorted TbO7 hexagonal pyramids that share corners with two equivalent Tb(2)O7 pentagonal bipyramids,  a cornercorner with one Ti(1)O5 trigonal bipyramid, edges with four equivalent Tb(1)O7 hexagonal pyramids, edges with three equivalent Tb(2)O7 pentagonal bipyramids, and edges with two equivalent Ti(1)O5 trigonal bipyramids. In the second Tb site, Tb(2) is bonded to one O(1), one O(2), one O(3), two equivalent O(4), and two equivalent O(5) atoms to form distorted TbO7 pentagonal bipyramids that share corners with two equivalent Tb(1)O7 hexagonal pyramids, corners with three equivalent Ti(1)O5 trigonal bipyramids, edges with three equivalent Tb(1)O7 hexagonal pyramids, edges with two equivalent Tb(2)O7 pentagonal bipyramids, and edges with two equivalent Ti(1)O5 trigonal bipyramids. Ti(1) is bonded to one O(1), one O(4), one O(5), and two equivalent O(3) atoms to form distorted TiO5 trigonal bipyramids that share  a cornercorner with one Tb(1)O7 hexagonal pyramid, corners with three equivalent Tb(2)O7 pentagonal bipyramids, corners with two equivalent Ti(1)O5 trigonal bipyramids, edges with two equivalent Tb(1)O7 hexagonal pyramids, and edges with two equivalent Tb(2)O7 pentagonal bipyramids. There are five inequivalent O sites. In the first O site, O(1) is bonded to one Tb(2), two equivalent Tb(1), and one Ti(1) atom to form OTb3Ti tetrahedra that share  a cornercorner with one O(3)Tb2Ti2 tetrahedra,  a cornercorner with one O(5)Tb3Ti tetrahedra, corners with two equivalent O(1)Tb3Ti tetrahedra, corners with five equivalent O(2)Tb4 tetrahedra,  an edgeedge with one O(2)Tb4 tetrahedra, edges with two equivalent O(3)Tb2Ti2 tetrahedra, and edges with two equivalent O(5)Tb3Ti tetrahedra. In the second O site, O(2) is bonded to one Tb(2) and three equivalent Tb(1) atoms to form OTb4 tetrahedra that share corners with two equivalent O(3)Tb2Ti2 tetrahedra, corners with two equivalent O(2)Tb4 tetrahedra, corners with five equivalent O(1)Tb3Ti tetrahedra, corners with five equivalent O(5)Tb3Ti tetrahedra,  an edgeedge with one O(3)Tb2Ti2 tetrahedra,  an edgeedge with one O(1)Tb3Ti tetrahedra, and edges with two equivalent O(2)Tb4 tetrahedra. In the third O site, O(3) is bonded to one Tb(1), one Tb(2), and two equivalent Ti(1) atoms to form distorted OTb2Ti2 tetrahedra that share  a cornercorner with one O(1)Tb3Ti tetrahedra,  a cornercorner with one O(5)Tb3Ti tetrahedra, corners with two equivalent O(3)Tb2Ti2 tetrahedra, corners with two equivalent O(2)Tb4 tetrahedra,  an edgeedge with one O(2)Tb4 tetrahedra, edges with two equivalent O(1)Tb3Ti tetrahedra, and edges with two equivalent O(5)Tb3Ti tetrahedra. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to two equivalent Tb(2) and one Ti(1) atom. In the fifth O site, O(5) is bonded to one Tb(1), two equivalent Tb(2), and one Ti(1) atom to form OTb3Ti tetrahedra that share  a cornercorner with one O(3)Tb2Ti2 tetrahedra,  a cornercorner with one O(1)Tb3Ti tetrahedra, corners with two equivalent O(5)Tb3Ti tetrahedra, corners with five equivalent O(2)Tb4 tetrahedra, edges with two equivalent O(3)Tb2Ti2 tetrahedra, and edges with two equivalent O(1)Tb3Ti tetrahedra. is represented by the CIF card [CIF]
data_Tb2TiO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.701
_cell_length_b   10.389
_cell_length_c   11.278
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   433.671
_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
  Tb  Tb0  1  0.250  0.136  0.944  1.0
  Tb  Tb1  1  0.250  0.636  0.556  1.0
  Tb  Tb2  1  0.750  0.864  0.056  1.0
  Tb  Tb3  1  0.750  0.364  0.444  1.0
  Tb  Tb4  1  0.750  0.386  0.777  1.0
  Tb  Tb5  1  0.750  0.886  0.723  1.0
  Tb  Tb6  1  0.250  0.614  0.223  1.0
  Tb  Tb7  1  0.250  0.114  0.277  1.0
  Ti  Ti8  1  0.250  0.175  0.620  1.0
  Ti  Ti9  1  0.250  0.675  0.880  1.0
  Ti  Ti10  1  0.750  0.825  0.380  1.0
  Ti  Ti11  1  0.750  0.325  0.120  1.0
  O  O12  1  0.250  0.224  0.458  1.0
  O  O13  1  0.250  0.724  0.042  1.0
  O  O14  1  0.750  0.776  0.542  1.0
  O  O15  1  0.750  0.276  0.958  1.0
  O  O16  1  0.250  0.493  0.395  1.0
  O  O17  1  0.250  0.993  0.105  1.0
  O  O18  1  0.750  0.507  0.605  1.0
  O  O19  1  0.750  0.007  0.895  1.0
  O  O20  1  0.250  0.263  0.117  1.0
  O  O21  1  0.250  0.763  0.383  1.0
  O  O22  1  0.750  0.737  0.883  1.0
  O  O23  1  0.750  0.237  0.617  1.0
  O  O24  1  0.250  0.008  0.654  1.0
  O  O25  1  0.250  0.508  0.846  1.0
  O  O26  1  0.750  0.992  0.346  1.0
  O  O27  1  0.750  0.492  0.154  1.0
  O  O28  1  0.250  0.257  0.770  1.0
  O  O29  1  0.250  0.757  0.730  1.0
  O  O30  1  0.750  0.743  0.230  1.0
  O  O31  1  0.750  0.243  0.270  1.0
[/CIF]
.