The crystal structure described by TbMg3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Tb(1) atoms to form distorted MgTb4Mg8 cuboctahedra that share corners with four equivalent Tb(1)Mg12 cuboctahedra; corners with fourteen Mg(1,1)Tb4Mg8 cuboctahedra; edges with six equivalent Tb(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Tb4Mg8 cuboctahedra; faces with four equivalent Tb(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1)Tb4Mg8 cuboctahedra. In the second Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Tb(1) atoms to form distorted MgTb4Mg8 cuboctahedra that share corners with four equivalent Tb(1)Mg12 cuboctahedra; corners with fourteen Mg(1,1)Tb4Mg8 cuboctahedra; edges with six equivalent Tb(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Tb4Mg8 cuboctahedra; faces with four equivalent Tb(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1)Tb4Mg8 cuboctahedra. Tb(1) is bonded to twelve Mg(1,1) atoms to form TbMg12 cuboctahedra that share corners with six equivalent Tb(1)Mg12 cuboctahedra; corners with twelve Mg(1,1)Tb4Mg8 cuboctahedra; edges with eighteen Mg(1,1)Tb4Mg8 cuboctahedra; faces with eight equivalent Tb(1)Mg12 cuboctahedra; and faces with twelve Mg(1,1)Tb4Mg8 cuboctahedra. is represented by the CIF card [CIF]
data_TbMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.677
_cell_length_b   6.677
_cell_length_c   5.168
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   199.516
_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  0.667  0.333  0.250  1.0
  Tb  Tb1  1  0.333  0.667  0.750  1.0
  Mg  Mg2  1  0.163  0.326  0.250  1.0
  Mg  Mg3  1  0.674  0.837  0.250  1.0
  Mg  Mg4  1  0.163  0.837  0.250  1.0
  Mg  Mg5  1  0.837  0.163  0.750  1.0
  Mg  Mg6  1  0.326  0.163  0.750  1.0
  Mg  Mg7  1  0.837  0.674  0.750  1.0
[/CIF]
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The crystal structure described by TbMg3 is beta Cu3Ti-like structured and crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Tb(1) atoms to form distorted MgTb4Mg8 cuboctahedra that share corners with four equivalent Tb(1)Mg12 cuboctahedra; corners with fourteen Mg(1,1)Tb4Mg8 cuboctahedra; edges with six equivalent Tb(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Tb4Mg8 cuboctahedra; faces with four equivalent Tb(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1)Tb4Mg8 cuboctahedra. In the second Mg site, Mg(1) is bonded to eight Mg(1,1) and four equivalent Tb(1) atoms to form distorted MgTb4Mg8 cuboctahedra that share corners with four equivalent Tb(1)Mg12 cuboctahedra; corners with fourteen Mg(1,1)Tb4Mg8 cuboctahedra; edges with six equivalent Tb(1)Mg12 cuboctahedra; edges with twelve Mg(1,1)Tb4Mg8 cuboctahedra; faces with four equivalent Tb(1)Mg12 cuboctahedra; and faces with sixteen Mg(1,1)Tb4Mg8 cuboctahedra. Tb(1) is bonded to twelve Mg(1,1) atoms to form TbMg12 cuboctahedra that share corners with six equivalent Tb(1)Mg12 cuboctahedra; corners with twelve Mg(1,1)Tb4Mg8 cuboctahedra; edges with eighteen Mg(1,1)Tb4Mg8 cuboctahedra; faces with eight equivalent Tb(1)Mg12 cuboctahedra; and faces with twelve Mg(1,1)Tb4Mg8 cuboctahedra. is represented by the CIF card [CIF]
data_TbMg3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.677
_cell_length_b   6.677
_cell_length_c   5.168
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   199.516
_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  0.667  0.333  0.250  1.0
  Tb  Tb1  1  0.333  0.667  0.750  1.0
  Mg  Mg2  1  0.163  0.326  0.250  1.0
  Mg  Mg3  1  0.674  0.837  0.250  1.0
  Mg  Mg4  1  0.163  0.837  0.250  1.0
  Mg  Mg5  1  0.837  0.163  0.750  1.0
  Mg  Mg6  1  0.326  0.163  0.750  1.0
  Mg  Mg7  1  0.837  0.674  0.750  1.0
[/CIF]
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