The compound described by TbNbO4 crystallizes in the monoclinic P2_1/c space group. Tb(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), three equivalent O(3), and three equivalent O(4) atoms. Nb(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 38-50°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Tb(1) and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Tb(1) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to three equivalent Tb(1) and one Nb(1) atom. In the fourth O site, O(4) is bonded to three equivalent Tb(1) and one Nb(1) atom to form a mixture of distorted corner and edge-sharing OTb3Nb tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TbNbO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.387
_cell_length_b   7.612
_cell_length_c   7.673
_cell_angle_alpha   81.569
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   311.214
_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  0.280  0.645  0.609  1.0
  Tb  Tb1  1  0.220  0.645  0.109  1.0
  Tb  Tb2  1  0.780  0.355  0.891  1.0
  Tb  Tb3  1  0.720  0.355  0.391  1.0
  Nb  Nb4  1  0.768  0.835  0.811  1.0
  Nb  Nb5  1  0.732  0.835  0.311  1.0
  Nb  Nb6  1  0.268  0.165  0.689  1.0
  Nb  Nb7  1  0.232  0.165  0.189  1.0
  O  O8  1  0.103  0.934  0.689  1.0
  O  O9  1  0.397  0.934  0.189  1.0
  O  O10  1  0.628  0.828  0.562  1.0
  O  O11  1  0.872  0.828  0.062  1.0
  O  O12  1  0.500  0.672  0.880  1.0
  O  O13  1  0.991  0.610  0.828  1.0
  O  O14  1  0.000  0.672  0.380  1.0
  O  O15  1  0.509  0.610  0.328  1.0
  O  O16  1  0.491  0.390  0.672  1.0
  O  O17  1  1.000  0.328  0.620  1.0
  O  O18  1  0.009  0.390  0.172  1.0
  O  O19  1  0.500  0.328  0.120  1.0
  O  O20  1  0.128  0.172  0.938  1.0
  O  O21  1  0.372  0.172  0.438  1.0
  O  O22  1  0.603  0.066  0.811  1.0
  O  O23  1  0.897  0.066  0.311  1.0
[/CIF]
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The compound described by TbNbO4 crystallizes in the monoclinic P2_1/c space group. Tb(1) is bonded in a 8-coordinate geometry to one O(1), one O(2), three equivalent O(3), and three equivalent O(4) atoms. Nb(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form corner-sharing NbO6 octahedra. The corner-sharing octahedral tilt angles range from 38-50°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Tb(1) and two equivalent Nb(1) atoms. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Tb(1) and two equivalent Nb(1) atoms. In the third O site, O(3) is bonded in a 4-coordinate geometry to three equivalent Tb(1) and one Nb(1) atom. In the fourth O site, O(4) is bonded to three equivalent Tb(1) and one Nb(1) atom to form a mixture of distorted corner and edge-sharing OTb3Nb tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_TbNbO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.387
_cell_length_b   7.612
_cell_length_c   7.673
_cell_angle_alpha   81.569
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   311.214
_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  0.280  0.645  0.609  1.0
  Tb  Tb1  1  0.220  0.645  0.109  1.0
  Tb  Tb2  1  0.780  0.355  0.891  1.0
  Tb  Tb3  1  0.720  0.355  0.391  1.0
  Nb  Nb4  1  0.768  0.835  0.811  1.0
  Nb  Nb5  1  0.732  0.835  0.311  1.0
  Nb  Nb6  1  0.268  0.165  0.689  1.0
  Nb  Nb7  1  0.232  0.165  0.189  1.0
  O  O8  1  0.103  0.934  0.689  1.0
  O  O9  1  0.397  0.934  0.189  1.0
  O  O10  1  0.628  0.828  0.562  1.0
  O  O11  1  0.872  0.828  0.062  1.0
  O  O12  1  0.500  0.672  0.880  1.0
  O  O13  1  0.991  0.610  0.828  1.0
  O  O14  1  0.000  0.672  0.380  1.0
  O  O15  1  0.509  0.610  0.328  1.0
  O  O16  1  0.491  0.390  0.672  1.0
  O  O17  1  1.000  0.328  0.620  1.0
  O  O18  1  0.009  0.390  0.172  1.0
  O  O19  1  0.500  0.328  0.120  1.0
  O  O20  1  0.128  0.172  0.938  1.0
  O  O21  1  0.372  0.172  0.438  1.0
  O  O22  1  0.603  0.066  0.811  1.0
  O  O23  1  0.897  0.066  0.311  1.0
[/CIF]
.