The material described by La6Fe9Al4As crystallizes in the tetragonal I4/mcm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 13-coordinate geometry to four equivalent Fe(1), four equivalent Fe(3), four equivalent Al(1), and one As(1) atom. In the second La site, La(2) is bonded in a 6-coordinate geometry to one Fe(3), three equivalent Al(1), and two equivalent As(1) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent La(1), one Fe(2), three equivalent Fe(1), four equivalent Fe(3), and two equivalent Al(1) atoms to form FeLa2Al2Fe8 cuboctahedra that share  a cornercorner with one Fe(2)Al4Fe8 cuboctahedra, corners with three equivalent Fe(1)La2Al2Fe8 cuboctahedra, faces with two equivalent Fe(2)Al4Fe8 cuboctahedra, and faces with seven equivalent Fe(1)La2Al2Fe8 cuboctahedra. In the second Fe site, Fe(2) is bonded to four equivalent Fe(1), four equivalent Fe(3), and four equivalent Al(1) atoms to form a mixture of corner and face-sharing FeAl4Fe8 cuboctahedra. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to one La(2), two equivalent La(1), one Fe(2), one Fe(3), four equivalent Fe(1), and three equivalent Al(1) atoms. Al(1) is bonded in a 12-coordinate geometry to two equivalent La(1), three equivalent La(2), one Fe(2), two equivalent Fe(1), three equivalent Fe(3), and one Al(1) atom. As(1) is bonded in a distorted q6 geometry to two equivalent La(1) and eight equivalent La(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_La6Al4Fe9As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.162
_cell_length_b   8.162
_cell_length_c   13.230
_cell_angle_alpha   107.968
_cell_angle_beta   107.968
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   793.125
_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
  La  La0  1  0.105  0.105  0.211  1.0
  La  La1  1  0.895  0.895  0.789  1.0
  La  La2  1  0.395  0.395  0.789  1.0
  La  La3  1  0.605  0.605  0.211  1.0
  La  La4  1  0.356  0.856  0.378  1.0
  La  La5  1  0.644  0.144  0.622  1.0
  La  La6  1  0.022  0.522  0.378  1.0
  La  La7  1  0.522  0.356  0.378  1.0
  La  La8  1  0.144  0.978  0.622  1.0
  La  La9  1  0.978  0.478  0.622  1.0
  La  La10  1  0.478  0.644  0.622  1.0
  La  La11  1  0.856  0.022  0.378  1.0
  Al  Al12  1  0.710  0.210  0.183  1.0
  Al  Al13  1  0.290  0.790  0.817  1.0
  Al  Al14  1  0.473  0.973  0.183  1.0
  Al  Al15  1  0.973  0.710  0.183  1.0
  Al  Al16  1  0.790  0.527  0.817  1.0
  Al  Al17  1  0.527  0.027  0.817  1.0
  Al  Al18  1  0.027  0.290  0.817  1.0
  Al  Al19  1  0.210  0.473  0.183  1.0
  Fe  Fe20  1  0.067  0.211  0.000  1.0
  Fe  Fe21  1  0.933  0.789  0.000  1.0
  Fe  Fe22  1  0.789  0.067  0.000  1.0
  Fe  Fe23  1  0.433  0.711  0.000  1.0
  Fe  Fe24  1  0.211  0.933  0.000  1.0
  Fe  Fe25  1  0.567  0.289  0.000  1.0
  Fe  Fe26  1  0.711  0.567  0.000  1.0
  Fe  Fe27  1  0.289  0.433  0.000  1.0
  Fe  Fe28  1  0.000  0.500  0.000  1.0
  Fe  Fe29  1  0.500  0.000  0.000  1.0
  Fe  Fe30  1  0.232  0.732  0.111  1.0
  Fe  Fe31  1  0.768  0.268  0.889  1.0
  Fe  Fe32  1  0.880  0.380  0.111  1.0
  Fe  Fe33  1  0.380  0.232  0.111  1.0
  Fe  Fe34  1  0.268  0.120  0.889  1.0
  Fe  Fe35  1  0.120  0.620  0.889  1.0
  Fe  Fe36  1  0.620  0.768  0.889  1.0
  Fe  Fe37  1  0.732  0.880  0.111  1.0
  As  As38  1  0.250  0.250  0.500  1.0
  As  As39  1  0.750  0.750  0.500  1.0
[/CIF]
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The material described by La6Fe9Al4As crystallizes in the tetragonal I4/mcm space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 13-coordinate geometry to four equivalent Fe(1), four equivalent Fe(3), four equivalent Al(1), and one As(1) atom. In the second La site, La(2) is bonded in a 6-coordinate geometry to one Fe(3), three equivalent Al(1), and two equivalent As(1) atoms. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent La(1), one Fe(2), three equivalent Fe(1), four equivalent Fe(3), and two equivalent Al(1) atoms to form FeLa2Al2Fe8 cuboctahedra that share  a cornercorner with one Fe(2)Al4Fe8 cuboctahedra, corners with three equivalent Fe(1)La2Al2Fe8 cuboctahedra, faces with two equivalent Fe(2)Al4Fe8 cuboctahedra, and faces with seven equivalent Fe(1)La2Al2Fe8 cuboctahedra. In the second Fe site, Fe(2) is bonded to four equivalent Fe(1), four equivalent Fe(3), and four equivalent Al(1) atoms to form a mixture of corner and face-sharing FeAl4Fe8 cuboctahedra. In the third Fe site, Fe(3) is bonded in a 12-coordinate geometry to one La(2), two equivalent La(1), one Fe(2), one Fe(3), four equivalent Fe(1), and three equivalent Al(1) atoms. Al(1) is bonded in a 12-coordinate geometry to two equivalent La(1), three equivalent La(2), one Fe(2), two equivalent Fe(1), three equivalent Fe(3), and one Al(1) atom. As(1) is bonded in a distorted q6 geometry to two equivalent La(1) and eight equivalent La(2) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_La6Al4Fe9As
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.162
_cell_length_b   8.162
_cell_length_c   13.230
_cell_angle_alpha   107.968
_cell_angle_beta   107.968
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   793.125
_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
  La  La0  1  0.105  0.105  0.211  1.0
  La  La1  1  0.895  0.895  0.789  1.0
  La  La2  1  0.395  0.395  0.789  1.0
  La  La3  1  0.605  0.605  0.211  1.0
  La  La4  1  0.356  0.856  0.378  1.0
  La  La5  1  0.644  0.144  0.622  1.0
  La  La6  1  0.022  0.522  0.378  1.0
  La  La7  1  0.522  0.356  0.378  1.0
  La  La8  1  0.144  0.978  0.622  1.0
  La  La9  1  0.978  0.478  0.622  1.0
  La  La10  1  0.478  0.644  0.622  1.0
  La  La11  1  0.856  0.022  0.378  1.0
  Al  Al12  1  0.710  0.210  0.183  1.0
  Al  Al13  1  0.290  0.790  0.817  1.0
  Al  Al14  1  0.473  0.973  0.183  1.0
  Al  Al15  1  0.973  0.710  0.183  1.0
  Al  Al16  1  0.790  0.527  0.817  1.0
  Al  Al17  1  0.527  0.027  0.817  1.0
  Al  Al18  1  0.027  0.290  0.817  1.0
  Al  Al19  1  0.210  0.473  0.183  1.0
  Fe  Fe20  1  0.067  0.211  0.000  1.0
  Fe  Fe21  1  0.933  0.789  0.000  1.0
  Fe  Fe22  1  0.789  0.067  0.000  1.0
  Fe  Fe23  1  0.433  0.711  0.000  1.0
  Fe  Fe24  1  0.211  0.933  0.000  1.0
  Fe  Fe25  1  0.567  0.289  0.000  1.0
  Fe  Fe26  1  0.711  0.567  0.000  1.0
  Fe  Fe27  1  0.289  0.433  0.000  1.0
  Fe  Fe28  1  0.000  0.500  0.000  1.0
  Fe  Fe29  1  0.500  0.000  0.000  1.0
  Fe  Fe30  1  0.232  0.732  0.111  1.0
  Fe  Fe31  1  0.768  0.268  0.889  1.0
  Fe  Fe32  1  0.880  0.380  0.111  1.0
  Fe  Fe33  1  0.380  0.232  0.111  1.0
  Fe  Fe34  1  0.268  0.120  0.889  1.0
  Fe  Fe35  1  0.120  0.620  0.889  1.0
  Fe  Fe36  1  0.620  0.768  0.889  1.0
  Fe  Fe37  1  0.732  0.880  0.111  1.0
  As  As38  1  0.250  0.250  0.500  1.0
  As  As39  1  0.750  0.750  0.500  1.0
[/CIF]
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