The structure described by Eu2Au2Al6Si3 crystallizes in the tetragonal I4mm space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 16-coordinate geometry to four equivalent Au(2), four equivalent Al(1), four equivalent Al(3), and four equivalent Si(2) atoms. In the second Eu site, Eu(2) is bonded in a 16-coordinate geometry to four equivalent Al(2), four equivalent Al(3), four equivalent Si(1), and four equivalent Si(3) atoms. There are two inequivalent Au sites. In the first Au site, Au(1) is bonded in a body-centered cubic geometry to four equivalent Al(1) and four equivalent Al(2) atoms. In the second Au site, Au(2) is bonded in a 5-coordinate geometry to four equivalent Eu(1), four equivalent Al(1), and one Si(2) atom. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Eu(1), two equivalent Au(1), and two equivalent Au(2) atoms to form distorted AlEu2Au4 tetrahedra that share corners with two equivalent Al(1)Eu2Au4 tetrahedra, corners with six equivalent Al(2)Eu2Si2Au2 tetrahedra, corners with six equivalent Al(3)Eu4Si4 tetrahedra,  an edgeedge with one Al(2)Eu2Si2Au2 tetrahedra,  an edgeedge with one Al(3)Eu4Si4 tetrahedra, edges with two equivalent Al(1)Eu2Au4 tetrahedra, and faces with four equivalent Al(1)Eu2Au4 tetrahedra. In the second Al site, Al(2) is bonded to two equivalent Eu(2), two equivalent Au(1), and two equivalent Si(1) atoms to form distorted AlEu2Si2Au2 tetrahedra that share corners with two equivalent Al(2)Eu2Si2Au2 tetrahedra, corners with six equivalent Al(1)Eu2Au4 tetrahedra, corners with six equivalent Al(3)Eu4Si4 tetrahedra,  an edgeedge with one Al(1)Eu2Au4 tetrahedra,  an edgeedge with one Al(3)Eu4Si4 tetrahedra, edges with two equivalent Al(2)Eu2Si2Au2 tetrahedra, and faces with four equivalent Al(2)Eu2Si2Au2 tetrahedra. In the third Al site, Al(3) is bonded to two equivalent Eu(1), two equivalent Eu(2), two equivalent Si(2), and two equivalent Si(3) atoms to form distorted AlEu4Si4 tetrahedra that share corners with six equivalent Al(1)Eu2Au4 tetrahedra, corners with six equivalent Al(2)Eu2Si2Au2 tetrahedra,  an edgeedge with one Al(1)Eu2Au4 tetrahedra,  an edgeedge with one Al(2)Eu2Si2Au2 tetrahedra, edges with four equivalent Al(3)Eu4Si4 tetrahedra, and faces with four equivalent Al(3)Eu4Si4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent Eu(2), four equivalent Al(2), and one Si(3) atom. In the second Si site, Si(2) is bonded in a 5-coordinate geometry to four equivalent Eu(1), one Au(2), and four equivalent Al(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Eu(2), four equivalent Al(3), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Eu2Al6Si3Au2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.561
_cell_length_b   13.561
_cell_length_c   13.561
_cell_angle_alpha   161.297
_cell_angle_beta   161.297
_cell_angle_gamma   26.570
_symmetry_Int_Tables_number   1
_cell_volume   256.333
_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
  Eu  Eu0  1  0.152  0.152  0.000  1.0
  Eu  Eu1  1  0.851  0.851  0.000  1.0
  Al  Al2  1  0.054  0.554  0.500  1.0
  Al  Al3  1  0.554  0.054  0.500  1.0
  Al  Al4  1  0.944  0.444  0.500  1.0
  Al  Al5  1  0.444  0.944  0.500  1.0
  Al  Al6  1  0.251  0.751  0.500  1.0
  Al  Al7  1  0.751  0.251  0.500  1.0
  Si  Si8  1  0.394  0.394  0.000  1.0
  Si  Si9  1  0.701  0.701  0.000  1.0
  Si  Si10  1  0.302  0.302  0.000  1.0
  Au  Au11  1  0.997  0.997  0.000  1.0
  Au  Au12  1  0.606  0.606  0.000  1.0
[/CIF]
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The structure described by Eu2Au2Al6Si3 crystallizes in the tetragonal I4mm space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 16-coordinate geometry to four equivalent Au(2), four equivalent Al(1), four equivalent Al(3), and four equivalent Si(2) atoms. In the second Eu site, Eu(2) is bonded in a 16-coordinate geometry to four equivalent Al(2), four equivalent Al(3), four equivalent Si(1), and four equivalent Si(3) atoms. There are two inequivalent Au sites. In the first Au site, Au(1) is bonded in a body-centered cubic geometry to four equivalent Al(1) and four equivalent Al(2) atoms. In the second Au site, Au(2) is bonded in a 5-coordinate geometry to four equivalent Eu(1), four equivalent Al(1), and one Si(2) atom. There are three inequivalent Al sites. In the first Al site, Al(1) is bonded to two equivalent Eu(1), two equivalent Au(1), and two equivalent Au(2) atoms to form distorted AlEu2Au4 tetrahedra that share corners with two equivalent Al(1)Eu2Au4 tetrahedra, corners with six equivalent Al(2)Eu2Si2Au2 tetrahedra, corners with six equivalent Al(3)Eu4Si4 tetrahedra,  an edgeedge with one Al(2)Eu2Si2Au2 tetrahedra,  an edgeedge with one Al(3)Eu4Si4 tetrahedra, edges with two equivalent Al(1)Eu2Au4 tetrahedra, and faces with four equivalent Al(1)Eu2Au4 tetrahedra. In the second Al site, Al(2) is bonded to two equivalent Eu(2), two equivalent Au(1), and two equivalent Si(1) atoms to form distorted AlEu2Si2Au2 tetrahedra that share corners with two equivalent Al(2)Eu2Si2Au2 tetrahedra, corners with six equivalent Al(1)Eu2Au4 tetrahedra, corners with six equivalent Al(3)Eu4Si4 tetrahedra,  an edgeedge with one Al(1)Eu2Au4 tetrahedra,  an edgeedge with one Al(3)Eu4Si4 tetrahedra, edges with two equivalent Al(2)Eu2Si2Au2 tetrahedra, and faces with four equivalent Al(2)Eu2Si2Au2 tetrahedra. In the third Al site, Al(3) is bonded to two equivalent Eu(1), two equivalent Eu(2), two equivalent Si(2), and two equivalent Si(3) atoms to form distorted AlEu4Si4 tetrahedra that share corners with six equivalent Al(1)Eu2Au4 tetrahedra, corners with six equivalent Al(2)Eu2Si2Au2 tetrahedra,  an edgeedge with one Al(1)Eu2Au4 tetrahedra,  an edgeedge with one Al(2)Eu2Si2Au2 tetrahedra, edges with four equivalent Al(3)Eu4Si4 tetrahedra, and faces with four equivalent Al(3)Eu4Si4 tetrahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded in a 9-coordinate geometry to four equivalent Eu(2), four equivalent Al(2), and one Si(3) atom. In the second Si site, Si(2) is bonded in a 5-coordinate geometry to four equivalent Eu(1), one Au(2), and four equivalent Al(3) atoms. In the third Si site, Si(3) is bonded in a 9-coordinate geometry to four equivalent Eu(2), four equivalent Al(3), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Eu2Al6Si3Au2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.561
_cell_length_b   13.561
_cell_length_c   13.561
_cell_angle_alpha   161.297
_cell_angle_beta   161.297
_cell_angle_gamma   26.570
_symmetry_Int_Tables_number   1
_cell_volume   256.333
_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
  Eu  Eu0  1  0.152  0.152  0.000  1.0
  Eu  Eu1  1  0.851  0.851  0.000  1.0
  Al  Al2  1  0.054  0.554  0.500  1.0
  Al  Al3  1  0.554  0.054  0.500  1.0
  Al  Al4  1  0.944  0.444  0.500  1.0
  Al  Al5  1  0.444  0.944  0.500  1.0
  Al  Al6  1  0.251  0.751  0.500  1.0
  Al  Al7  1  0.751  0.251  0.500  1.0
  Si  Si8  1  0.394  0.394  0.000  1.0
  Si  Si9  1  0.701  0.701  0.000  1.0
  Si  Si10  1  0.302  0.302  0.000  1.0
  Au  Au11  1  0.997  0.997  0.000  1.0
  Au  Au12  1  0.606  0.606  0.000  1.0
[/CIF]
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