data_Zr2AlSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.41
_cell_length_b   8.41
_cell_length_c   8.41
_cell_angle_alpha   23.57
_cell_angle_beta   23.57
_cell_angle_gamma   23.57
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Zr2AlSe
_chemical_formula_sum   'Zr2 Al1 Se1'
_cell_volume   83.47
_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
  Zr  Zr2  1  0.0  0.0  0.98  1.0
  Zr  Zr3  1  0.0  0.0  0.53  1.0
  Al  Al0  1  0.0  0.0  0.0  1.0
  Se  Se1  1  0.0  0.0  0.26  1.0

data_Zr2AlSe
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.95
_cell_length_b   3.43
_cell_length_c   8.41
_cell_angle_alpha   90.0
_cell_angle_beta   103.64
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Zr2AlSe
_chemical_formula_sum   'Zr4 Al2 Se2'
_cell_volume   166.94
_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
  Zr  Zr0  2  0.0  0.0  0.02  1.0
  Zr  Zr1  2  0.0  0.0  0.47  1.0
  Al  Al2  2  0.0  0.0  0.0  1.0
  Se  Se3  2  0.0  0.0  0.74  1.0

Zr Zr Al Se
Zr Zr Al Se 0 2 o o + 0 3 o o + 1 3 o o o 2 3 o o o 
Zr2AlSe is Cyanogen Chloride-like structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Zr2AlSe clusters. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a single-bond geometry to one Al(1) atom. The Zr(1)-Al(1) bond length is 0.14 Å. In the second Zr site, Zr(2) is bonded in a single-bond geometry to one Se(1) atom. The Zr(2)-Se(1) bond length is 2.29 Å. Al(1) is bonded in a distorted single-bond geometry to one Zr(1) and one Se(1) atom. The Al(1)-Se(1) bond length is 2.15 Å. Se(1) is bonded in a linear geometry to one Zr(2) and one Al(1) atom.