The structure described by Tb2Si3 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to two equivalent Si(3), four equivalent Si(2), and six equivalent Si(1) atoms to form a mixture of distorted face and edge-sharing TbSi12 cuboctahedra. In the second Tb site, Tb(2) is bonded in a 7-coordinate geometry to two equivalent Si(2) and five equivalent Si(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to six equivalent Tb(1), one Si(2), and two equivalent Si(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Tb(2), four equivalent Tb(1), one Si(1), and two equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Tb(1), five equivalent Tb(2), and two equivalent Si(2) atoms. is represented by the CIF file [CIF]
data_Tb2Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.934
_cell_length_b   4.170
_cell_length_c   12.418
_cell_angle_alpha   99.676
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   200.800
_cell_formula_units_Z   2
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  0.750  0.431  0.862  1.0
  Tb  Tb1  1  0.250  0.569  0.138  1.0
  Tb  Tb2  1  0.750  0.702  0.405  1.0
  Tb  Tb3  1  0.250  0.298  0.595  1.0
  Si  Si4  1  0.750  0.024  0.049  1.0
  Si  Si5  1  0.250  0.976  0.951  1.0
  Si  Si6  1  0.750  0.119  0.238  1.0
  Si  Si7  1  0.250  0.881  0.762  1.0
  Si  Si8  1  0.750  0.824  0.647  1.0
  Si  Si9  1  0.250  0.176  0.353  1.0
[/CIF]
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The structure described by Tb2Si3 crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to two equivalent Si(3), four equivalent Si(2), and six equivalent Si(1) atoms to form a mixture of distorted face and edge-sharing TbSi12 cuboctahedra. In the second Tb site, Tb(2) is bonded in a 7-coordinate geometry to two equivalent Si(2) and five equivalent Si(3) atoms. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to six equivalent Tb(1), one Si(2), and two equivalent Si(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to two equivalent Tb(2), four equivalent Tb(1), one Si(1), and two equivalent Si(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to two equivalent Tb(1), five equivalent Tb(2), and two equivalent Si(2) atoms. is represented by the CIF file [CIF]
data_Tb2Si3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.934
_cell_length_b   4.170
_cell_length_c   12.418
_cell_angle_alpha   99.676
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   200.800
_cell_formula_units_Z   2
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  0.750  0.431  0.862  1.0
  Tb  Tb1  1  0.250  0.569  0.138  1.0
  Tb  Tb2  1  0.750  0.702  0.405  1.0
  Tb  Tb3  1  0.250  0.298  0.595  1.0
  Si  Si4  1  0.750  0.024  0.049  1.0
  Si  Si5  1  0.250  0.976  0.951  1.0
  Si  Si6  1  0.750  0.119  0.238  1.0
  Si  Si7  1  0.250  0.881  0.762  1.0
  Si  Si8  1  0.750  0.824  0.647  1.0
  Si  Si9  1  0.250  0.176  0.353  1.0
[/CIF]
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