The crystal structure described by Tb3Fe2Si7 crystallizes in the orthorhombic Amm2 space group. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 14-coordinate geometry to four equivalent Fe(1), two equivalent Si(4), two equivalent Si(5), two equivalent Si(7), and four equivalent Si(2) atoms. In the second Tb site, Tb(2) is bonded in a 14-coordinate geometry to four equivalent Fe(2), two equivalent Si(1), two equivalent Si(2), two equivalent Si(3), and four equivalent Si(4) atoms. In the third Tb site, Tb(3) is bonded in a 14-coordinate geometry to one Fe(1), one Fe(2), two equivalent Si(1), two equivalent Si(3), two equivalent Si(5), two equivalent Si(7), and four equivalent Si(6) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 5-coordinate geometry to one Tb(3), four equivalent Tb(1), one Si(2), two equivalent Si(5), and two equivalent Si(7) atoms. In the second Fe site, Fe(2) is bonded in a 5-coordinate geometry to one Tb(3), four equivalent Tb(2), one Si(4), two equivalent Si(1), and two equivalent Si(3) atoms. There are seven inequivalent Si sites. In the first Si site, Si(1) is bonded in a 2-coordinate geometry to two equivalent Tb(2), two equivalent Tb(3), and two equivalent Fe(2) 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 Fe(1), and two equivalent Si(4) atoms. In the third Si site, Si(3) is bonded in a 2-coordinate geometry to two equivalent Tb(2), two equivalent Tb(3), and two equivalent Fe(2) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Tb(1), four equivalent Tb(2), one Fe(2), and two equivalent Si(2) atoms. In the fifth Si site, Si(5) is bonded in a 6-coordinate geometry to two equivalent Tb(1), two equivalent Tb(3), and two equivalent Fe(1) atoms. In the sixth Si site, Si(6) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Tb(3) atoms. In the seventh Si site, Si(7) is bonded in a 6-coordinate geometry to two equivalent Tb(1), two equivalent Tb(3), and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_Tb3Fe2Si7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.450
_cell_length_b   12.450
_cell_length_c   4.095
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   161.322
_symmetry_Int_Tables_number   1
_cell_volume   203.268
_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
  Tb  Tb0  1  0.097  0.903  0.500  1.0
  Tb  Tb1  1  0.467  0.533  0.500  1.0
  Tb  Tb2  1  0.782  0.218  0.000  1.0
  Fe  Fe3  1  0.655  0.345  0.000  1.0
  Fe  Fe4  1  0.910  0.090  0.000  1.0
  Si  Si5  1  0.371  0.629  0.000  1.0
  Si  Si6  1  0.563  0.437  0.000  1.0
  Si  Si7  1  0.872  0.128  0.500  1.0
  Si  Si8  1  0.003  0.997  0.000  1.0
  Si  Si9  1  0.193  0.807  0.000  1.0
  Si  Si10  1  0.291  0.709  0.500  1.0
  Si  Si11  1  0.693  0.307  0.500  1.0
[/CIF]
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The crystal structure described by Tb3Fe2Si7 crystallizes in the orthorhombic Amm2 space group. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 14-coordinate geometry to four equivalent Fe(1), two equivalent Si(4), two equivalent Si(5), two equivalent Si(7), and four equivalent Si(2) atoms. In the second Tb site, Tb(2) is bonded in a 14-coordinate geometry to four equivalent Fe(2), two equivalent Si(1), two equivalent Si(2), two equivalent Si(3), and four equivalent Si(4) atoms. In the third Tb site, Tb(3) is bonded in a 14-coordinate geometry to one Fe(1), one Fe(2), two equivalent Si(1), two equivalent Si(3), two equivalent Si(5), two equivalent Si(7), and four equivalent Si(6) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 5-coordinate geometry to one Tb(3), four equivalent Tb(1), one Si(2), two equivalent Si(5), and two equivalent Si(7) atoms. In the second Fe site, Fe(2) is bonded in a 5-coordinate geometry to one Tb(3), four equivalent Tb(2), one Si(4), two equivalent Si(1), and two equivalent Si(3) atoms. There are seven inequivalent Si sites. In the first Si site, Si(1) is bonded in a 2-coordinate geometry to two equivalent Tb(2), two equivalent Tb(3), and two equivalent Fe(2) 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 Fe(1), and two equivalent Si(4) atoms. In the third Si site, Si(3) is bonded in a 2-coordinate geometry to two equivalent Tb(2), two equivalent Tb(3), and two equivalent Fe(2) atoms. In the fourth Si site, Si(4) is bonded in a 9-coordinate geometry to two equivalent Tb(1), four equivalent Tb(2), one Fe(2), and two equivalent Si(2) atoms. In the fifth Si site, Si(5) is bonded in a 6-coordinate geometry to two equivalent Tb(1), two equivalent Tb(3), and two equivalent Fe(1) atoms. In the sixth Si site, Si(6) is bonded in a distorted rectangular see-saw-like geometry to four equivalent Tb(3) atoms. In the seventh Si site, Si(7) is bonded in a 6-coordinate geometry to two equivalent Tb(1), two equivalent Tb(3), and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_Tb3Fe2Si7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.450
_cell_length_b   12.450
_cell_length_c   4.095
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   161.322
_symmetry_Int_Tables_number   1
_cell_volume   203.268
_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
  Tb  Tb0  1  0.097  0.903  0.500  1.0
  Tb  Tb1  1  0.467  0.533  0.500  1.0
  Tb  Tb2  1  0.782  0.218  0.000  1.0
  Fe  Fe3  1  0.655  0.345  0.000  1.0
  Fe  Fe4  1  0.910  0.090  0.000  1.0
  Si  Si5  1  0.371  0.629  0.000  1.0
  Si  Si6  1  0.563  0.437  0.000  1.0
  Si  Si7  1  0.872  0.128  0.500  1.0
  Si  Si8  1  0.003  0.997  0.000  1.0
  Si  Si9  1  0.193  0.807  0.000  1.0
  Si  Si10  1  0.291  0.709  0.500  1.0
  Si  Si11  1  0.693  0.307  0.500  1.0
[/CIF]
.