data_Zr2SiSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.85
_cell_length_b   3.85
_cell_length_c   5.44
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Zr2SiSe
_chemical_formula_sum   'Zr2 Si1 Se1'
_cell_volume   80.78
_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  0.93  0.93  0.0  1.0
  Zr  Zr3  1  0.0  0.0  0.72  1.0
  Si  Si1  1  0.0  0.0  0.0  1.0
  Se  Se0  1  0.93  0.93  0.72  1.0

data_Zr2SiSe
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.45
_cell_length_b   5.45
_cell_length_c   5.44
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Zr2SiSe
_chemical_formula_sum   'Zr4 Si2 Se2'
_cell_volume   161.56
_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  0.72  1.0
  Zr  Zr1  2  0.43  0.5  -0.0  1.0
  Si  Si2  2  0.0  0.0  0.0  1.0
  Se  Se3  2  0.43  0.5  0.72  1.0

Zr Zr Si Se
Zr2SiSe crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Zr2SiSe clusters. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a distorted L-shaped geometry to one Si(1) and one Se(1) atom. The Zr(1)-Si(1) bond length is 0.40 Å. The Zr(1)-Se(1) bond length is 1.53 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 0.40 Å. Si(1) is bonded in a distorted single-bond geometry to one Zr(1) atom. Se(1) is bonded in a distorted single-bond geometry to one Zr(1) and one Zr(2) atom.