The material described by Mg3(TaAl9)2 crystallizes in the cubic Fd-3m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 14-coordinate geometry to two equivalent Mg(2) and twelve equivalent Al(2) atoms. In the second Mg site, Mg(2) is bonded in a 16-coordinate geometry to four equivalent Mg(1) and twelve equivalent Al(2) atoms. Ta(1) is bonded to six equivalent Al(1) and six equivalent Al(2) atoms to form TaAl12 cuboctahedra that share corners with six equivalent Ta(1)Al12 cuboctahedra, edges with eighteen equivalent Al(2)Mg3TaAl8 cuboctahedra, and faces with six equivalent Al(2)Mg3TaAl8 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent Ta(1), four equivalent Al(1), and six equivalent Al(2) atoms. In the second Al site, Al(2) is bonded to one Mg(2), two equivalent Mg(1), one Ta(1), three equivalent Al(1), and five equivalent Al(2) atoms to form AlMg3TaAl8 cuboctahedra that share corners with fifteen equivalent Al(2)Mg3TaAl8 cuboctahedra, edges with two equivalent Al(2)Mg3TaAl8 cuboctahedra, edges with three equivalent Ta(1)Al12 cuboctahedra,  a faceface with one Ta(1)Al12 cuboctahedra, and faces with fifteen equivalent Al(2)Mg3TaAl8 cuboctahedra. is represented by the CIF file [CIF]
data_Mg3(TaAl9)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.404
_cell_length_b   10.404
_cell_length_c   10.404
_cell_angle_alpha   59.998
_cell_angle_beta   59.998
_cell_angle_gamma   59.998
_symmetry_Int_Tables_number   1
_cell_volume   796.296
_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
  Mg  Mg0  1  0.125  0.625  0.625  1.0
  Mg  Mg1  1  0.625  0.125  0.625  1.0
  Mg  Mg2  1  0.625  0.625  0.125  1.0
  Mg  Mg3  1  0.625  0.625  0.625  1.0
  Mg  Mg4  1  0.500  0.500  0.500  1.0
  Mg  Mg5  1  0.750  0.750  0.750  1.0
  Ta  Ta6  1  0.625  0.125  0.125  1.0
  Ta  Ta7  1  0.125  0.625  0.125  1.0
  Ta  Ta8  1  0.125  0.125  0.625  1.0
  Ta  Ta9  1  0.125  0.125  0.125  1.0
  Al  Al10  1  0.858  0.858  0.142  1.0
  Al  Al11  1  0.142  0.142  0.858  1.0
  Al  Al12  1  0.858  0.142  0.858  1.0
  Al  Al13  1  0.142  0.858  0.142  1.0
  Al  Al14  1  0.142  0.858  0.858  1.0
  Al  Al15  1  0.858  0.142  0.142  1.0
  Al  Al16  1  0.392  0.392  0.108  1.0
  Al  Al17  1  0.108  0.108  0.392  1.0
  Al  Al18  1  0.392  0.108  0.392  1.0
  Al  Al19  1  0.108  0.392  0.108  1.0
  Al  Al20  1  0.108  0.392  0.392  1.0
  Al  Al21  1  0.392  0.108  0.108  1.0
  Al  Al22  1  0.567  0.302  0.302  1.0
  Al  Al23  1  0.302  0.567  0.830  1.0
  Al  Al24  1  0.302  0.830  0.567  1.0
  Al  Al25  1  0.830  0.302  0.302  1.0
  Al  Al26  1  0.302  0.302  0.567  1.0
  Al  Al27  1  0.567  0.830  0.302  1.0
  Al  Al28  1  0.830  0.567  0.302  1.0
  Al  Al29  1  0.302  0.302  0.830  1.0
  Al  Al30  1  0.302  0.567  0.302  1.0
  Al  Al31  1  0.830  0.302  0.567  1.0
  Al  Al32  1  0.567  0.302  0.830  1.0
  Al  Al33  1  0.302  0.830  0.302  1.0
  Al  Al34  1  0.683  0.948  0.948  1.0
  Al  Al35  1  0.948  0.683  0.420  1.0
  Al  Al36  1  0.948  0.420  0.683  1.0
  Al  Al37  1  0.420  0.948  0.948  1.0
  Al  Al38  1  0.948  0.948  0.683  1.0
  Al  Al39  1  0.683  0.420  0.948  1.0
  Al  Al40  1  0.420  0.683  0.948  1.0
  Al  Al41  1  0.948  0.948  0.420  1.0
  Al  Al42  1  0.948  0.683  0.948  1.0
  Al  Al43  1  0.420  0.948  0.683  1.0
  Al  Al44  1  0.683  0.948  0.420  1.0
  Al  Al45  1  0.948  0.420  0.948  1.0
[/CIF]
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The material described by Mg3(TaAl9)2 crystallizes in the cubic Fd-3m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 14-coordinate geometry to two equivalent Mg(2) and twelve equivalent Al(2) atoms. In the second Mg site, Mg(2) is bonded in a 16-coordinate geometry to four equivalent Mg(1) and twelve equivalent Al(2) atoms. Ta(1) is bonded to six equivalent Al(1) and six equivalent Al(2) atoms to form TaAl12 cuboctahedra that share corners with six equivalent Ta(1)Al12 cuboctahedra, edges with eighteen equivalent Al(2)Mg3TaAl8 cuboctahedra, and faces with six equivalent Al(2)Mg3TaAl8 cuboctahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent Ta(1), four equivalent Al(1), and six equivalent Al(2) atoms. In the second Al site, Al(2) is bonded to one Mg(2), two equivalent Mg(1), one Ta(1), three equivalent Al(1), and five equivalent Al(2) atoms to form AlMg3TaAl8 cuboctahedra that share corners with fifteen equivalent Al(2)Mg3TaAl8 cuboctahedra, edges with two equivalent Al(2)Mg3TaAl8 cuboctahedra, edges with three equivalent Ta(1)Al12 cuboctahedra,  a faceface with one Ta(1)Al12 cuboctahedra, and faces with fifteen equivalent Al(2)Mg3TaAl8 cuboctahedra. is represented by the CIF file [CIF]
data_Mg3(TaAl9)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.404
_cell_length_b   10.404
_cell_length_c   10.404
_cell_angle_alpha   59.998
_cell_angle_beta   59.998
_cell_angle_gamma   59.998
_symmetry_Int_Tables_number   1
_cell_volume   796.296
_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
  Mg  Mg0  1  0.125  0.625  0.625  1.0
  Mg  Mg1  1  0.625  0.125  0.625  1.0
  Mg  Mg2  1  0.625  0.625  0.125  1.0
  Mg  Mg3  1  0.625  0.625  0.625  1.0
  Mg  Mg4  1  0.500  0.500  0.500  1.0
  Mg  Mg5  1  0.750  0.750  0.750  1.0
  Ta  Ta6  1  0.625  0.125  0.125  1.0
  Ta  Ta7  1  0.125  0.625  0.125  1.0
  Ta  Ta8  1  0.125  0.125  0.625  1.0
  Ta  Ta9  1  0.125  0.125  0.125  1.0
  Al  Al10  1  0.858  0.858  0.142  1.0
  Al  Al11  1  0.142  0.142  0.858  1.0
  Al  Al12  1  0.858  0.142  0.858  1.0
  Al  Al13  1  0.142  0.858  0.142  1.0
  Al  Al14  1  0.142  0.858  0.858  1.0
  Al  Al15  1  0.858  0.142  0.142  1.0
  Al  Al16  1  0.392  0.392  0.108  1.0
  Al  Al17  1  0.108  0.108  0.392  1.0
  Al  Al18  1  0.392  0.108  0.392  1.0
  Al  Al19  1  0.108  0.392  0.108  1.0
  Al  Al20  1  0.108  0.392  0.392  1.0
  Al  Al21  1  0.392  0.108  0.108  1.0
  Al  Al22  1  0.567  0.302  0.302  1.0
  Al  Al23  1  0.302  0.567  0.830  1.0
  Al  Al24  1  0.302  0.830  0.567  1.0
  Al  Al25  1  0.830  0.302  0.302  1.0
  Al  Al26  1  0.302  0.302  0.567  1.0
  Al  Al27  1  0.567  0.830  0.302  1.0
  Al  Al28  1  0.830  0.567  0.302  1.0
  Al  Al29  1  0.302  0.302  0.830  1.0
  Al  Al30  1  0.302  0.567  0.302  1.0
  Al  Al31  1  0.830  0.302  0.567  1.0
  Al  Al32  1  0.567  0.302  0.830  1.0
  Al  Al33  1  0.302  0.830  0.302  1.0
  Al  Al34  1  0.683  0.948  0.948  1.0
  Al  Al35  1  0.948  0.683  0.420  1.0
  Al  Al36  1  0.948  0.420  0.683  1.0
  Al  Al37  1  0.420  0.948  0.948  1.0
  Al  Al38  1  0.948  0.948  0.683  1.0
  Al  Al39  1  0.683  0.420  0.948  1.0
  Al  Al40  1  0.420  0.683  0.948  1.0
  Al  Al41  1  0.948  0.948  0.420  1.0
  Al  Al42  1  0.948  0.683  0.948  1.0
  Al  Al43  1  0.420  0.948  0.683  1.0
  Al  Al44  1  0.683  0.948  0.420  1.0
  Al  Al45  1  0.948  0.420  0.948  1.0
[/CIF]
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