The material described by LiTb2(PO4)2 is Esseneite-like structured and crystallizes in the monoclinic C2 space group. Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and edges with two equivalent P(1)O4 tetrahedra. Tb(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Li(1)O6 octahedra and  an edgeedge with one Li(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), two equivalent Tb(1), and one P(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Li(1), two equivalent Tb(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), two equivalent Tb(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Tb(1) and one P(1) atom. is represented by the CIF file [CIF]
data_LiTb2(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.784
_cell_length_b   6.146
_cell_length_c   6.146
_cell_angle_alpha   110.441
_cell_angle_beta   102.986
_cell_angle_gamma   117.828
_symmetry_Int_Tables_number   1
_cell_volume   159.998
_cell_formula_units_Z   1
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
  Li  Li0  1  0.000  0.260  0.260  1.0
  Tb  Tb1  1  0.180  0.879  0.276  1.0
  Tb  Tb2  1  0.820  0.096  0.700  1.0
  P  P3  1  0.378  0.617  0.763  1.0
  P  P4  1  0.622  0.386  0.239  1.0
  O  O5  1  0.764  0.357  0.049  1.0
  O  O6  1  0.717  0.822  0.934  1.0
  O  O7  1  0.312  0.710  0.565  1.0
  O  O8  1  0.790  0.718  0.409  1.0
  O  O9  1  0.283  0.217  0.105  1.0
  O  O10  1  0.210  0.619  0.929  1.0
  O  O11  1  0.236  0.285  0.592  1.0
  O  O12  1  0.688  0.252  0.398  1.0
[/CIF]
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The material described by LiTb2(PO4)2 is Esseneite-like structured and crystallizes in the monoclinic C2 space group. Li(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form LiO6 octahedra that share corners with two equivalent P(1)O4 tetrahedra and edges with two equivalent P(1)O4 tetrahedra. Tb(1) is bonded in a 8-coordinate geometry to two equivalent O(1), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. P(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form PO4 tetrahedra that share  a cornercorner with one Li(1)O6 octahedra and  an edgeedge with one Li(1)O6 octahedra. The corner-sharing octahedral tilt angles are 49°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), two equivalent Tb(1), and one P(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Li(1), two equivalent Tb(1), and one P(1) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), two equivalent Tb(1), and one P(1) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Tb(1) and one P(1) atom. is represented by the CIF file [CIF]
data_LiTb2(PO4)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.784
_cell_length_b   6.146
_cell_length_c   6.146
_cell_angle_alpha   110.441
_cell_angle_beta   102.986
_cell_angle_gamma   117.828
_symmetry_Int_Tables_number   1
_cell_volume   159.998
_cell_formula_units_Z   1
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
  Li  Li0  1  0.000  0.260  0.260  1.0
  Tb  Tb1  1  0.180  0.879  0.276  1.0
  Tb  Tb2  1  0.820  0.096  0.700  1.0
  P  P3  1  0.378  0.617  0.763  1.0
  P  P4  1  0.622  0.386  0.239  1.0
  O  O5  1  0.764  0.357  0.049  1.0
  O  O6  1  0.717  0.822  0.934  1.0
  O  O7  1  0.312  0.710  0.565  1.0
  O  O8  1  0.790  0.718  0.409  1.0
  O  O9  1  0.283  0.217  0.105  1.0
  O  O10  1  0.210  0.619  0.929  1.0
  O  O11  1  0.236  0.285  0.592  1.0
  O  O12  1  0.688  0.252  0.398  1.0
[/CIF]
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