data_Zr2Fe2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.92
_cell_length_b   4.92
_cell_length_c   4.92
_cell_angle_alpha   118.99
_cell_angle_beta   118.99
_cell_angle_gamma   91.76
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Zr2Fe2Si
_chemical_formula_sum   'Zr2 Fe2 Si1'
_cell_volume   85.25
_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  Zr3  1  0.0  0.5  0.71  1.0
  Zr  Zr4  1  0.5  0.0  0.71  1.0
  Fe  Fe0  1  0.0  0.0  0.62  1.0
  Fe  Fe1  1  0.0  0.0  0.23  1.0
  Si  Si2  1  0.0  0.0  0.0  1.0

data_Zr2Fe2Si
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.85
_cell_length_b   7.06
_cell_length_c   4.92
_cell_angle_alpha   90.0
_cell_angle_beta   134.12
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Zr2Fe2Si
_chemical_formula_sum   'Zr4 Fe4 Si2'
_cell_volume   170.51
_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  4  0.25  0.25  0.29  1.0
  Fe  Fe1  2  0.0  0.0  0.38  1.0
  Fe  Fe2  2  0.0  0.0  0.77  1.0
  Si  Si3  2  0.0  0.0  0.0  1.0

Zr Zr Fe Fe Si
Zr Zr Fe Fe Si 0 4 o + + 0 3 o + + 0 3 o o o 0 2 o o o 1 3 o o o 1 3 + o + 1 2 o o o 1 4 + o + 2 3 o o o 2 4 o o + 3 4 o o o 
Zr2Fe2Si crystallizes in the monoclinic Cm space group. Zr(1) is bonded in a 5-coordinate geometry to two equivalent Fe(1), two equivalent Fe(2), and one Si(1) atom. There is one shorter (2.25 Å) and one longer (2.73 Å) Zr(1)-Fe(1) bond length. There is one shorter (2.44 Å) and one longer (2.55 Å) Zr(1)-Fe(2) bond length. The Zr(1)-Si(1) bond length is 2.18 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 6-coordinate geometry to four equivalent Zr(1), one Fe(2), and one Si(1) atom. The Fe(1)-Fe(2) bond length is 1.91 Å. The Fe(1)-Si(1) bond length is 1.88 Å. In the second Fe site, Fe(2) is bonded in a distorted single-bond geometry to four equivalent Zr(1), one Fe(1), and one Si(1) atom. The Fe(2)-Si(1) bond length is 1.12 Å. Si(1) is bonded in a distorted see-saw-like geometry to two equivalent Zr(1), one Fe(1), and one Fe(2) atom.