The structure described by Tb4SiBr6 is trigonal omega-derived structured and crystallizes in the orthorhombic Pbam space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to one Si(1), one Br(1), two equivalent Br(2), and two equivalent Br(3) atoms to form TbSiBr5 octahedra that share  a cornercorner with one Tb(1)SiBr5 octahedra, corners with two equivalent Tb(2)Si2Br4 octahedra, edges with two equivalent Tb(1)SiBr5 octahedra, and edges with four equivalent Tb(2)Si2Br4 octahedra. The corner-sharing octahedral tilt angles range from 0-48°. In the second Tb site, Tb(2) is bonded to two equivalent Si(1), one Br(2), one Br(3), and two equivalent Br(1) atoms to form TbSi2Br4 octahedra that share corners with two equivalent Tb(2)Si2Br4 octahedra, corners with two equivalent Tb(1)SiBr5 octahedra, edges with three equivalent Tb(2)Si2Br4 octahedra, and edges with four equivalent Tb(1)SiBr5 octahedra. The corner-sharing octahedral tilt angles range from 0-48°. Si(1) is bonded to two equivalent Tb(1) and four equivalent Tb(2) atoms to form edge-sharing SiTb6 octahedra. There are three inequivalent Br sites. In the first Br site, Br(1) is bonded in a distorted T-shaped geometry to one Tb(1) and two equivalent Tb(2) atoms. In the second Br site, Br(2) is bonded in a distorted T-shaped geometry to one Tb(2) and two equivalent Tb(1) atoms. In the third Br site, Br(3) is bonded in a distorted T-shaped geometry to one Tb(2) and two equivalent Tb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb4SiBr6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.057
_cell_length_b   13.211
_cell_length_c   13.994
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   749.922
_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  0.500  0.118  0.341  1.0
  Tb  Tb1  1  0.500  0.882  0.659  1.0
  Tb  Tb2  1  0.500  0.618  0.159  1.0
  Tb  Tb3  1  0.500  0.382  0.841  1.0
  Tb  Tb4  1  0.000  0.118  0.579  1.0
  Tb  Tb5  1  0.000  0.882  0.421  1.0
  Tb  Tb6  1  0.000  0.618  0.921  1.0
  Tb  Tb7  1  0.000  0.382  0.079  1.0
  Si  Si8  1  0.500  0.000  0.500  1.0
  Si  Si9  1  0.500  0.500  0.000  1.0
  Br  Br10  1  0.500  0.244  0.164  1.0
  Br  Br11  1  0.500  0.756  0.836  1.0
  Br  Br12  1  0.500  0.744  0.336  1.0
  Br  Br13  1  0.500  0.256  0.664  1.0
  Br  Br14  1  0.000  0.256  0.411  1.0
  Br  Br15  1  0.000  0.744  0.589  1.0
  Br  Br16  1  0.000  0.756  0.089  1.0
  Br  Br17  1  0.000  0.244  0.911  1.0
  Br  Br18  1  0.000  0.002  0.242  1.0
  Br  Br19  1  0.000  0.998  0.758  1.0
  Br  Br20  1  0.000  0.502  0.258  1.0
  Br  Br21  1  0.000  0.498  0.742  1.0
[/CIF]
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The structure described by Tb4SiBr6 is trigonal omega-derived structured and crystallizes in the orthorhombic Pbam space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded to one Si(1), one Br(1), two equivalent Br(2), and two equivalent Br(3) atoms to form TbSiBr5 octahedra that share  a cornercorner with one Tb(1)SiBr5 octahedra, corners with two equivalent Tb(2)Si2Br4 octahedra, edges with two equivalent Tb(1)SiBr5 octahedra, and edges with four equivalent Tb(2)Si2Br4 octahedra. The corner-sharing octahedral tilt angles range from 0-48°. In the second Tb site, Tb(2) is bonded to two equivalent Si(1), one Br(2), one Br(3), and two equivalent Br(1) atoms to form TbSi2Br4 octahedra that share corners with two equivalent Tb(2)Si2Br4 octahedra, corners with two equivalent Tb(1)SiBr5 octahedra, edges with three equivalent Tb(2)Si2Br4 octahedra, and edges with four equivalent Tb(1)SiBr5 octahedra. The corner-sharing octahedral tilt angles range from 0-48°. Si(1) is bonded to two equivalent Tb(1) and four equivalent Tb(2) atoms to form edge-sharing SiTb6 octahedra. There are three inequivalent Br sites. In the first Br site, Br(1) is bonded in a distorted T-shaped geometry to one Tb(1) and two equivalent Tb(2) atoms. In the second Br site, Br(2) is bonded in a distorted T-shaped geometry to one Tb(2) and two equivalent Tb(1) atoms. In the third Br site, Br(3) is bonded in a distorted T-shaped geometry to one Tb(2) and two equivalent Tb(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb4SiBr6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.057
_cell_length_b   13.211
_cell_length_c   13.994
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   749.922
_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  0.500  0.118  0.341  1.0
  Tb  Tb1  1  0.500  0.882  0.659  1.0
  Tb  Tb2  1  0.500  0.618  0.159  1.0
  Tb  Tb3  1  0.500  0.382  0.841  1.0
  Tb  Tb4  1  0.000  0.118  0.579  1.0
  Tb  Tb5  1  0.000  0.882  0.421  1.0
  Tb  Tb6  1  0.000  0.618  0.921  1.0
  Tb  Tb7  1  0.000  0.382  0.079  1.0
  Si  Si8  1  0.500  0.000  0.500  1.0
  Si  Si9  1  0.500  0.500  0.000  1.0
  Br  Br10  1  0.500  0.244  0.164  1.0
  Br  Br11  1  0.500  0.756  0.836  1.0
  Br  Br12  1  0.500  0.744  0.336  1.0
  Br  Br13  1  0.500  0.256  0.664  1.0
  Br  Br14  1  0.000  0.256  0.411  1.0
  Br  Br15  1  0.000  0.744  0.589  1.0
  Br  Br16  1  0.000  0.756  0.089  1.0
  Br  Br17  1  0.000  0.244  0.911  1.0
  Br  Br18  1  0.000  0.002  0.242  1.0
  Br  Br19  1  0.000  0.998  0.758  1.0
  Br  Br20  1  0.000  0.502  0.258  1.0
  Br  Br21  1  0.000  0.498  0.742  1.0
[/CIF]
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