The material structure described by LaAlSi2 crystallizes in the trigonal P-3m1 space group. La(1) is bonded in a 9-coordinate geometry to three equivalent Si(1) and six equivalent Si(2) atoms. Al(1) is bonded to four equivalent Si(1) atoms to form a mixture of corner and edge-sharing AlSi4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 7-coordinate geometry to three equivalent La(1) and four equivalent Al(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to six equivalent La(1) and three equivalent Si(2) atoms. is represented by the CIF file [CIF]
data_LaAlSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.167
_cell_length_b   4.167
_cell_length_c   11.531
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   173.423
_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  0.000  0.000  0.817  1.0
  La  La1  1  0.000  0.000  0.183  1.0
  Al  Al2  1  0.333  0.667  0.580  1.0
  Al  Al3  1  0.667  0.333  0.420  1.0
  Si  Si4  1  0.667  0.333  0.641  1.0
  Si  Si5  1  0.333  0.667  0.359  1.0
  Si  Si6  1  0.333  0.667  0.995  1.0
  Si  Si7  1  0.667  0.333  0.005  1.0
[/CIF]
.
The material structure described by LaAlSi2 crystallizes in the trigonal P-3m1 space group. La(1) is bonded in a 9-coordinate geometry to three equivalent Si(1) and six equivalent Si(2) atoms. Al(1) is bonded to four equivalent Si(1) atoms to form a mixture of corner and edge-sharing AlSi4 tetrahedra. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 7-coordinate geometry to three equivalent La(1) and four equivalent Al(1) atoms. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to six equivalent La(1) and three equivalent Si(2) atoms. is represented by the CIF file [CIF]
data_LaAlSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.167
_cell_length_b   4.167
_cell_length_c   11.531
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   173.423
_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  0.000  0.000  0.817  1.0
  La  La1  1  0.000  0.000  0.183  1.0
  Al  Al2  1  0.333  0.667  0.580  1.0
  Al  Al3  1  0.667  0.333  0.420  1.0
  Si  Si4  1  0.667  0.333  0.641  1.0
  Si  Si5  1  0.333  0.667  0.359  1.0
  Si  Si6  1  0.333  0.667  0.995  1.0
  Si  Si7  1  0.667  0.333  0.005  1.0
[/CIF]
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