data_AlCr2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.97
_cell_length_b   2.97
_cell_length_c   5.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   AlCr2Si
_chemical_formula_sum   'Al1 Cr2 Si1'
_cell_volume   51.0
_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  0.0  0.0  0.0  1.0
  Cr  Cr1  1  0.48  0.48  0.54  1.0
  Cr  Cr2  1  0.48  0.48  0.24  1.0
  Si  Si3  1  0.0  0.0  0.89  1.0

data_AlCr2Si
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.2
_cell_length_b   4.2
_cell_length_c   5.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   AlCr2Si
_chemical_formula_sum   'Al2 Cr4 Si2'
_cell_volume   101.99
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.0  0.0  0.0  1.0
  Cr  Cr1  2  0.48  0.0  0.24  1.0
  Cr  Cr2  2  0.48  0.0  0.54  1.0
  Si  Si3  2  0.0  0.0  0.89  1.0

Al Cr Cr Si
Cr2AlSi crystallizes in the monoclinic Cm space group. There are two inequivalent Cr sites. In the first Cr site, Cr(1) is bonded in a 9-coordinate geometry to one Cr(2), four equivalent Cr(1), and four equivalent Si(1) atoms. The Cr(1)-Cr(2) bond length is 1.73 Å. All Cr(1)-Cr(1) bond lengths are 2.97 Å. There are a spread of Cr(1)-Si(1) bond distances ranging from 2.87-2.96 Å. In the second Cr site, Cr(2) is bonded in a 5-coordinate geometry to one Cr(1) and four equivalent Al(1) atoms. There are a spread of Cr(2)-Al(1) bond distances ranging from 2.47-2.58 Å. Al(1) is bonded in a single-bond geometry to four equivalent Cr(2) and one Si(1) atom. The Al(1)-Si(1) bond length is 0.63 Å. Si(1) is bonded in a single-bond geometry to four equivalent Cr(1) and one Al(1) atom.