The crystal structure described by Mg5Tb9Ni4 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Tb(1), and four equivalent Tb(2) atoms. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to eight equivalent Tb(1) atoms. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a distorted L-shaped geometry to two equivalent Mg(2), four equivalent Mg(1), and two equivalent Ni(1) atoms. In the second Tb site, Tb(2) is bonded in a 4-coordinate geometry to four equivalent Mg(1) and four equivalent Ni(1) atoms. In the third Tb site, Tb(3) is bonded in a square co-planar geometry to four equivalent Ni(1) atoms. Ni(1) is bonded in a 7-coordinate geometry to one Tb(3), two equivalent Tb(1), and four equivalent Tb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb9Mg5Ni4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.925
_cell_length_b   10.925
_cell_length_c   3.631
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   433.403
_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  0.321  0.321  0.500  1.0
  Tb  Tb1  1  0.679  0.679  0.500  1.0
  Tb  Tb2  1  0.321  0.679  0.500  1.0
  Tb  Tb3  1  0.679  0.321  0.500  1.0
  Tb  Tb4  1  1.000  0.276  0.500  1.0
  Tb  Tb5  1  0.000  0.724  0.500  1.0
  Tb  Tb6  1  0.276  1.000  0.500  1.0
  Tb  Tb7  1  0.724  0.000  0.500  1.0
  Tb  Tb8  1  0.000  0.000  0.000  1.0
  Mg  Mg9  1  0.500  0.141  0.000  1.0
  Mg  Mg10  1  0.500  0.859  0.000  1.0
  Mg  Mg11  1  0.141  0.500  0.000  1.0
  Mg  Mg12  1  0.859  0.500  0.000  1.0
  Mg  Mg13  1  0.500  0.500  0.000  1.0
  Ni  Ni14  1  0.191  0.191  0.000  1.0
  Ni  Ni15  1  0.809  0.809  0.000  1.0
  Ni  Ni16  1  0.191  0.809  0.000  1.0
  Ni  Ni17  1  0.809  0.191  0.000  1.0
[/CIF]
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The crystal structure described by Mg5Tb9Ni4 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 9-coordinate geometry to one Mg(1), four equivalent Tb(1), and four equivalent Tb(2) atoms. In the second Mg site, Mg(2) is bonded in a body-centered cubic geometry to eight equivalent Tb(1) atoms. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a distorted L-shaped geometry to two equivalent Mg(2), four equivalent Mg(1), and two equivalent Ni(1) atoms. In the second Tb site, Tb(2) is bonded in a 4-coordinate geometry to four equivalent Mg(1) and four equivalent Ni(1) atoms. In the third Tb site, Tb(3) is bonded in a square co-planar geometry to four equivalent Ni(1) atoms. Ni(1) is bonded in a 7-coordinate geometry to one Tb(3), two equivalent Tb(1), and four equivalent Tb(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb9Mg5Ni4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.925
_cell_length_b   10.925
_cell_length_c   3.631
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   433.403
_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  0.321  0.321  0.500  1.0
  Tb  Tb1  1  0.679  0.679  0.500  1.0
  Tb  Tb2  1  0.321  0.679  0.500  1.0
  Tb  Tb3  1  0.679  0.321  0.500  1.0
  Tb  Tb4  1  1.000  0.276  0.500  1.0
  Tb  Tb5  1  0.000  0.724  0.500  1.0
  Tb  Tb6  1  0.276  1.000  0.500  1.0
  Tb  Tb7  1  0.724  0.000  0.500  1.0
  Tb  Tb8  1  0.000  0.000  0.000  1.0
  Mg  Mg9  1  0.500  0.141  0.000  1.0
  Mg  Mg10  1  0.500  0.859  0.000  1.0
  Mg  Mg11  1  0.141  0.500  0.000  1.0
  Mg  Mg12  1  0.859  0.500  0.000  1.0
  Mg  Mg13  1  0.500  0.500  0.000  1.0
  Ni  Ni14  1  0.191  0.191  0.000  1.0
  Ni  Ni15  1  0.809  0.809  0.000  1.0
  Ni  Ni16  1  0.191  0.809  0.000  1.0
  Ni  Ni17  1  0.809  0.191  0.000  1.0
[/CIF]
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