The compound described by MgTb4Ir crystallizes in the cubic F-43m space group. Mg(1) is bonded to three equivalent Mg(1), three equivalent Tb(1), three equivalent Tb(2), and three equivalent Tb(3) atoms to form a mixture of face and corner-sharing MgTb9Mg3 cuboctahedra. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a bent 150 degrees geometry to two equivalent Mg(1) and two equivalent Ir(1) atoms. In the second Tb site, Tb(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Ir(1) atoms. In the third Tb site, Tb(3) is bonded in a 3-coordinate geometry to three equivalent Mg(1) and three equivalent Ir(1) atoms. Ir(1) is bonded in a 6-coordinate geometry to three equivalent Tb(1), three equivalent Tb(2), and three equivalent Tb(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb4MgIr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.718
_cell_length_b   9.718
_cell_length_c   9.718
_cell_angle_alpha   59.999
_cell_angle_beta   60.000
_cell_angle_gamma   59.999
_symmetry_Int_Tables_number   1
_cell_volume   648.994
_cell_formula_units_Z   4
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  0.188  0.812  0.812  1.0
  Tb  Tb1  1  0.812  0.188  0.188  1.0
  Tb  Tb2  1  0.062  0.438  0.062  1.0
  Tb  Tb3  1  0.038  0.654  0.654  1.0
  Tb  Tb4  1  0.654  0.654  0.654  1.0
  Tb  Tb5  1  0.062  0.062  0.438  1.0
  Tb  Tb6  1  0.188  0.812  0.188  1.0
  Tb  Tb7  1  0.812  0.812  0.188  1.0
  Tb  Tb8  1  0.812  0.188  0.812  1.0
  Tb  Tb9  1  0.438  0.062  0.438  1.0
  Tb  Tb10  1  0.438  0.438  0.062  1.0
  Tb  Tb11  1  0.438  0.062  0.062  1.0
  Tb  Tb12  1  0.062  0.438  0.438  1.0
  Tb  Tb13  1  0.188  0.188  0.812  1.0
  Tb  Tb14  1  0.654  0.654  0.038  1.0
  Tb  Tb15  1  0.654  0.038  0.654  1.0
  Mg  Mg16  1  0.421  0.421  0.737  1.0
  Mg  Mg17  1  0.421  0.737  0.421  1.0
  Mg  Mg18  1  0.421  0.421  0.421  1.0
  Mg  Mg19  1  0.737  0.421  0.421  1.0
  Ir  Ir20  1  0.859  0.859  0.424  1.0
  Ir  Ir21  1  0.859  0.424  0.859  1.0
  Ir  Ir22  1  0.859  0.859  0.859  1.0
  Ir  Ir23  1  0.424  0.859  0.859  1.0
[/CIF]
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The compound described by MgTb4Ir crystallizes in the cubic F-43m space group. Mg(1) is bonded to three equivalent Mg(1), three equivalent Tb(1), three equivalent Tb(2), and three equivalent Tb(3) atoms to form a mixture of face and corner-sharing MgTb9Mg3 cuboctahedra. There are three inequivalent Tb sites. In the first Tb site, Tb(1) is bonded in a bent 150 degrees geometry to two equivalent Mg(1) and two equivalent Ir(1) atoms. In the second Tb site, Tb(2) is bonded in a 4-coordinate geometry to two equivalent Mg(1) and two equivalent Ir(1) atoms. In the third Tb site, Tb(3) is bonded in a 3-coordinate geometry to three equivalent Mg(1) and three equivalent Ir(1) atoms. Ir(1) is bonded in a 6-coordinate geometry to three equivalent Tb(1), three equivalent Tb(2), and three equivalent Tb(3) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tb4MgIr
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.718
_cell_length_b   9.718
_cell_length_c   9.718
_cell_angle_alpha   59.999
_cell_angle_beta   60.000
_cell_angle_gamma   59.999
_symmetry_Int_Tables_number   1
_cell_volume   648.994
_cell_formula_units_Z   4
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  0.188  0.812  0.812  1.0
  Tb  Tb1  1  0.812  0.188  0.188  1.0
  Tb  Tb2  1  0.062  0.438  0.062  1.0
  Tb  Tb3  1  0.038  0.654  0.654  1.0
  Tb  Tb4  1  0.654  0.654  0.654  1.0
  Tb  Tb5  1  0.062  0.062  0.438  1.0
  Tb  Tb6  1  0.188  0.812  0.188  1.0
  Tb  Tb7  1  0.812  0.812  0.188  1.0
  Tb  Tb8  1  0.812  0.188  0.812  1.0
  Tb  Tb9  1  0.438  0.062  0.438  1.0
  Tb  Tb10  1  0.438  0.438  0.062  1.0
  Tb  Tb11  1  0.438  0.062  0.062  1.0
  Tb  Tb12  1  0.062  0.438  0.438  1.0
  Tb  Tb13  1  0.188  0.188  0.812  1.0
  Tb  Tb14  1  0.654  0.654  0.038  1.0
  Tb  Tb15  1  0.654  0.038  0.654  1.0
  Mg  Mg16  1  0.421  0.421  0.737  1.0
  Mg  Mg17  1  0.421  0.737  0.421  1.0
  Mg  Mg18  1  0.421  0.421  0.421  1.0
  Mg  Mg19  1  0.737  0.421  0.421  1.0
  Ir  Ir20  1  0.859  0.859  0.424  1.0
  Ir  Ir21  1  0.859  0.424  0.859  1.0
  Ir  Ir22  1  0.859  0.859  0.859  1.0
  Ir  Ir23  1  0.424  0.859  0.859  1.0
[/CIF]
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