The crystal structure described by Mo12Al3Si crystallizes in the orthorhombic Pmmm space group. There are five inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 6-coordinate geometry to one Mo(1), one Mo(2), two equivalent Al(1), and two equivalent Si(1) atoms. In the second Mo site, Mo(2) is bonded in a 6-coordinate geometry to one Mo(1), one Mo(2), two equivalent Al(1), and two equivalent Al(2) atoms. In the third Mo site, Mo(3) is bonded in a 6-coordinate geometry to two equivalent Mo(3), two equivalent Al(1), and two equivalent Al(2) atoms. In the fourth Mo site, Mo(4) is bonded in a 6-coordinate geometry to two equivalent Mo(4), two equivalent Al(1), and two equivalent Si(1) atoms. In the fifth Mo site, Mo(5) is bonded in a 6-coordinate geometry to two equivalent Mo(5), one Al(2), two equivalent Al(1), and one Si(1) atom. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Mo(1), two equivalent Mo(2), two equivalent Mo(3), two equivalent Mo(4), and four equivalent Mo(5) atoms to form AlMo12 cuboctahedra that share edges with six equivalent Al(1)Mo12 cuboctahedra, faces with four equivalent Al(2)Mo12 cuboctahedra, and faces with four equivalent Si(1)Mo12 cuboctahedra. In the second Al site, Al(2) is bonded to four equivalent Mo(2), four equivalent Mo(3), and four equivalent Mo(5) atoms to form AlMo12 cuboctahedra that share edges with two equivalent Si(1)Mo12 cuboctahedra, edges with four equivalent Al(2)Mo12 cuboctahedra, and faces with eight equivalent Al(1)Mo12 cuboctahedra. Si(1) is bonded to four equivalent Mo(1), four equivalent Mo(4), and four equivalent Mo(5) atoms to form SiMo12 cuboctahedra that share edges with two equivalent Al(2)Mo12 cuboctahedra, edges with four equivalent Si(1)Mo12 cuboctahedra, and faces with eight equivalent Al(1)Mo12 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al3SiMo12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.970
_cell_length_b   4.969
_cell_length_c   9.924
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   245.067
_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
  Al  Al0  1  0.500  0.500  0.250  1.0
  Al  Al1  1  0.500  0.500  0.750  1.0
  Al  Al2  1  0.000  0.000  0.000  1.0
  Si  Si3  1  0.000  0.000  0.500  1.0
  Mo  Mo4  1  0.000  0.500  0.376  1.0
  Mo  Mo5  1  0.000  0.500  0.875  1.0
  Mo  Mo6  1  0.500  0.250  0.000  1.0
  Mo  Mo7  1  0.500  0.248  0.500  1.0
  Mo  Mo8  1  0.751  0.000  0.251  1.0
  Mo  Mo9  1  0.751  0.000  0.749  1.0
  Mo  Mo10  1  0.000  0.500  0.125  1.0
  Mo  Mo11  1  0.000  0.500  0.624  1.0
  Mo  Mo12  1  0.500  0.750  0.000  1.0
  Mo  Mo13  1  0.500  0.752  0.500  1.0
  Mo  Mo14  1  0.249  0.000  0.251  1.0
  Mo  Mo15  1  0.249  0.000  0.749  1.0
[/CIF]
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The crystal structure described by Mo12Al3Si crystallizes in the orthorhombic Pmmm space group. There are five inequivalent Mo sites. In the first Mo site, Mo(1) is bonded in a 6-coordinate geometry to one Mo(1), one Mo(2), two equivalent Al(1), and two equivalent Si(1) atoms. In the second Mo site, Mo(2) is bonded in a 6-coordinate geometry to one Mo(1), one Mo(2), two equivalent Al(1), and two equivalent Al(2) atoms. In the third Mo site, Mo(3) is bonded in a 6-coordinate geometry to two equivalent Mo(3), two equivalent Al(1), and two equivalent Al(2) atoms. In the fourth Mo site, Mo(4) is bonded in a 6-coordinate geometry to two equivalent Mo(4), two equivalent Al(1), and two equivalent Si(1) atoms. In the fifth Mo site, Mo(5) is bonded in a 6-coordinate geometry to two equivalent Mo(5), one Al(2), two equivalent Al(1), and one Si(1) atom. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Mo(1), two equivalent Mo(2), two equivalent Mo(3), two equivalent Mo(4), and four equivalent Mo(5) atoms to form AlMo12 cuboctahedra that share edges with six equivalent Al(1)Mo12 cuboctahedra, faces with four equivalent Al(2)Mo12 cuboctahedra, and faces with four equivalent Si(1)Mo12 cuboctahedra. In the second Al site, Al(2) is bonded to four equivalent Mo(2), four equivalent Mo(3), and four equivalent Mo(5) atoms to form AlMo12 cuboctahedra that share edges with two equivalent Si(1)Mo12 cuboctahedra, edges with four equivalent Al(2)Mo12 cuboctahedra, and faces with eight equivalent Al(1)Mo12 cuboctahedra. Si(1) is bonded to four equivalent Mo(1), four equivalent Mo(4), and four equivalent Mo(5) atoms to form SiMo12 cuboctahedra that share edges with two equivalent Al(2)Mo12 cuboctahedra, edges with four equivalent Si(1)Mo12 cuboctahedra, and faces with eight equivalent Al(1)Mo12 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Al3SiMo12
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.970
_cell_length_b   4.969
_cell_length_c   9.924
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   245.067
_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
  Al  Al0  1  0.500  0.500  0.250  1.0
  Al  Al1  1  0.500  0.500  0.750  1.0
  Al  Al2  1  0.000  0.000  0.000  1.0
  Si  Si3  1  0.000  0.000  0.500  1.0
  Mo  Mo4  1  0.000  0.500  0.376  1.0
  Mo  Mo5  1  0.000  0.500  0.875  1.0
  Mo  Mo6  1  0.500  0.250  0.000  1.0
  Mo  Mo7  1  0.500  0.248  0.500  1.0
  Mo  Mo8  1  0.751  0.000  0.251  1.0
  Mo  Mo9  1  0.751  0.000  0.749  1.0
  Mo  Mo10  1  0.000  0.500  0.125  1.0
  Mo  Mo11  1  0.000  0.500  0.624  1.0
  Mo  Mo12  1  0.500  0.750  0.000  1.0
  Mo  Mo13  1  0.500  0.752  0.500  1.0
  Mo  Mo14  1  0.249  0.000  0.251  1.0
  Mo  Mo15  1  0.249  0.000  0.749  1.0
[/CIF]
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