The material described by Tb3Cu4Si4 crystallizes in the orthorhombic Immm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 12-coordinate geometry to six equivalent Cu(1), two equivalent Si(2), and four equivalent Si(1) atoms. In the second Tb site, Tb(2) is bonded to two equivalent Si(2) and four equivalent Si(1) atoms to form distorted edge-sharing TbSi6 octahedra. Cu(1) is bonded in a 8-coordinate geometry to three equivalent Tb(1), one Cu(1), one Si(1), and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Tb(2), four equivalent Tb(1), two equivalent Cu(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Tb(2), two equivalent Tb(1), and six equivalent Cu(1) atoms. is represented by the CIF card [CIF]
data_Tb3(CuSi)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.141
_cell_length_b   6.519
_cell_length_c   7.856
_cell_angle_alpha   114.511
_cell_angle_beta   105.268
_cell_angle_gamma   90.009
_symmetry_Int_Tables_number   1
_cell_volume   184.693
_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  0.869  0.869  0.738  1.0
  Tb  Tb1  1  0.131  0.131  0.262  1.0
  Tb  Tb2  1  0.000  0.500  0.000  1.0
  Cu  Cu3  1  0.332  0.521  0.663  1.0
  Cu  Cu4  1  0.667  0.857  0.336  1.0
  Cu  Cu5  1  0.333  0.143  0.664  1.0
  Cu  Cu6  1  0.668  0.479  0.337  1.0
  Si  Si7  1  0.500  0.816  1.000  1.0
  Si  Si8  1  0.500  0.184  0.000  1.0
  Si  Si9  1  0.784  0.284  0.568  1.0
  Si  Si10  1  0.216  0.716  0.432  1.0
[/CIF]
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The material described by Tb3Cu4Si4 crystallizes in the orthorhombic Immm space group. There are two inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a 12-coordinate geometry to six equivalent Cu(1), two equivalent Si(2), and four equivalent Si(1) atoms. In the second Tb site, Tb(2) is bonded to two equivalent Si(2) and four equivalent Si(1) atoms to form distorted edge-sharing TbSi6 octahedra. Cu(1) is bonded in a 8-coordinate geometry to three equivalent Tb(1), one Cu(1), one Si(1), and three equivalent Si(2) atoms. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to two equivalent Tb(2), four equivalent Tb(1), two equivalent Cu(1), and one Si(1) atom. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to one Tb(2), two equivalent Tb(1), and six equivalent Cu(1) atoms. is represented by the CIF card [CIF]
data_Tb3(CuSi)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.141
_cell_length_b   6.519
_cell_length_c   7.856
_cell_angle_alpha   114.511
_cell_angle_beta   105.268
_cell_angle_gamma   90.009
_symmetry_Int_Tables_number   1
_cell_volume   184.693
_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  0.869  0.869  0.738  1.0
  Tb  Tb1  1  0.131  0.131  0.262  1.0
  Tb  Tb2  1  0.000  0.500  0.000  1.0
  Cu  Cu3  1  0.332  0.521  0.663  1.0
  Cu  Cu4  1  0.667  0.857  0.336  1.0
  Cu  Cu5  1  0.333  0.143  0.664  1.0
  Cu  Cu6  1  0.668  0.479  0.337  1.0
  Si  Si7  1  0.500  0.816  1.000  1.0
  Si  Si8  1  0.500  0.184  0.000  1.0
  Si  Si9  1  0.784  0.284  0.568  1.0
  Si  Si10  1  0.216  0.716  0.432  1.0
[/CIF]
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