The structure described by Tb2SiSeO4 crystallizes in the orthorhombic Pbcm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent O(2), and four equivalent O(1) atoms. In the second Tb site, Tb(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent O(1), and four equivalent O(2) atoms. Si(1) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(2) atoms. Se(1) is bonded in a 4-coordinate geometry to two equivalent Tb(1) and two equivalent Tb(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Tb(2), two equivalent Tb(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Tb(1), two equivalent Tb(2), and one Si(1) atom. is represented by the CIF file [CIF]
data_Tb2SiSeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.089
_cell_length_b   7.019
_cell_length_c   10.889
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   465.351
_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  0.390  0.750  0.500  1.0
  Tb  Tb1  1  0.390  0.750  0.000  1.0
  Tb  Tb2  1  0.610  0.250  0.500  1.0
  Tb  Tb3  1  0.610  0.250  0.000  1.0
  Tb  Tb4  1  0.867  0.970  0.750  1.0
  Tb  Tb5  1  0.867  0.530  0.250  1.0
  Tb  Tb6  1  0.133  0.470  0.750  1.0
  Tb  Tb7  1  0.133  0.030  0.250  1.0
  Si  Si8  1  0.115  0.250  0.000  1.0
  Si  Si9  1  0.885  0.750  0.000  1.0
  Si  Si10  1  0.885  0.750  0.500  1.0
  Si  Si11  1  0.115  0.250  0.500  1.0
  Se  Se12  1  0.571  0.629  0.750  1.0
  Se  Se13  1  0.571  0.871  0.250  1.0
  Se  Se14  1  0.429  0.129  0.750  1.0
  Se  Se15  1  0.429  0.371  0.250  1.0
  O  O16  1  0.277  0.069  0.468  1.0
  O  O17  1  0.277  0.431  0.532  1.0
  O  O18  1  0.723  0.569  0.032  1.0
  O  O19  1  0.723  0.931  0.968  1.0
  O  O20  1  0.723  0.931  0.532  1.0
  O  O21  1  0.723  0.569  0.468  1.0
  O  O22  1  0.277  0.431  0.968  1.0
  O  O23  1  0.277  0.069  0.032  1.0
  O  O24  1  0.051  0.761  0.380  1.0
  O  O25  1  0.051  0.761  0.120  1.0
  O  O26  1  0.949  0.261  0.120  1.0
  O  O27  1  0.949  0.239  0.880  1.0
  O  O28  1  0.949  0.239  0.620  1.0
  O  O29  1  0.949  0.261  0.380  1.0
  O  O30  1  0.051  0.739  0.880  1.0
  O  O31  1  0.051  0.739  0.620  1.0
[/CIF]
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The structure described by Tb2SiSeO4 crystallizes in the orthorhombic Pbcm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 6-coordinate geometry to two equivalent Se(1), two equivalent O(2), and four equivalent O(1) atoms. In the second Tb site, Tb(2) is bonded in a 8-coordinate geometry to two equivalent Se(1), two equivalent O(1), and four equivalent O(2) atoms. Si(1) is bonded in a tetrahedral geometry to two equivalent O(1) and two equivalent O(2) atoms. Se(1) is bonded in a 4-coordinate geometry to two equivalent Tb(1) and two equivalent Tb(2) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Tb(2), two equivalent Tb(1), and one Si(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Tb(1), two equivalent Tb(2), and one Si(1) atom. is represented by the CIF file [CIF]
data_Tb2SiSeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.089
_cell_length_b   7.019
_cell_length_c   10.889
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   465.351
_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  0.390  0.750  0.500  1.0
  Tb  Tb1  1  0.390  0.750  0.000  1.0
  Tb  Tb2  1  0.610  0.250  0.500  1.0
  Tb  Tb3  1  0.610  0.250  0.000  1.0
  Tb  Tb4  1  0.867  0.970  0.750  1.0
  Tb  Tb5  1  0.867  0.530  0.250  1.0
  Tb  Tb6  1  0.133  0.470  0.750  1.0
  Tb  Tb7  1  0.133  0.030  0.250  1.0
  Si  Si8  1  0.115  0.250  0.000  1.0
  Si  Si9  1  0.885  0.750  0.000  1.0
  Si  Si10  1  0.885  0.750  0.500  1.0
  Si  Si11  1  0.115  0.250  0.500  1.0
  Se  Se12  1  0.571  0.629  0.750  1.0
  Se  Se13  1  0.571  0.871  0.250  1.0
  Se  Se14  1  0.429  0.129  0.750  1.0
  Se  Se15  1  0.429  0.371  0.250  1.0
  O  O16  1  0.277  0.069  0.468  1.0
  O  O17  1  0.277  0.431  0.532  1.0
  O  O18  1  0.723  0.569  0.032  1.0
  O  O19  1  0.723  0.931  0.968  1.0
  O  O20  1  0.723  0.931  0.532  1.0
  O  O21  1  0.723  0.569  0.468  1.0
  O  O22  1  0.277  0.431  0.968  1.0
  O  O23  1  0.277  0.069  0.032  1.0
  O  O24  1  0.051  0.761  0.380  1.0
  O  O25  1  0.051  0.761  0.120  1.0
  O  O26  1  0.949  0.261  0.120  1.0
  O  O27  1  0.949  0.239  0.880  1.0
  O  O28  1  0.949  0.239  0.620  1.0
  O  O29  1  0.949  0.261  0.380  1.0
  O  O30  1  0.051  0.739  0.880  1.0
  O  O31  1  0.051  0.739  0.620  1.0
[/CIF]
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