data_FeRe2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.96
_cell_length_b   2.96
_cell_length_c   6.37
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   FeRe2Se
_chemical_formula_sum   'Fe1 Re2 Se1'
_cell_volume   55.68
_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
  Fe  Fe0  1  0.0  0.0  0.0  1.0
  Re  Re1  1  0.48  0.48  0.52  1.0
  Re  Re2  1  0.48  0.48  0.85  1.0
  Se  Se3  1  0.0  0.0  0.18  1.0

data_FeRe2Se
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.18
_cell_length_b   4.18
_cell_length_c   6.37
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   FeRe2Se
_chemical_formula_sum   'Fe2 Re4 Se2'
_cell_volume   111.35
_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
  Fe  Fe0  2  0.0  0.0  0.0  1.0
  Re  Re1  2  0.48  0.0  0.52  1.0
  Re  Re2  2  0.48  0.0  0.85  1.0
  Se  Se3  2  0.0  0.0  0.18  1.0

Fe Re Re Se
Fe Re Re Se 0 3 o o o 0 2 o o - 0 2 o - - 0 2 - o - 0 2 - - - 1 2 o o o 
Re2FeSe crystallizes in the monoclinic Cm space group. There are two inequivalent Re sites. In the first Re site, Re(1) is bonded in a 9-coordinate geometry to one Re(2), four equivalent Re(1), and four equivalent Se(1) atoms. The Re(1)-Re(2) bond length is 2.12 Å. All Re(1)-Re(1) bond lengths are 2.96 Å. There are a spread of Re(1)-Se(1) bond distances ranging from 2.92-3.04 Å. In the second Re site, Re(2) is bonded in a 5-coordinate geometry to one Re(1) and four equivalent Fe(1) atoms. There are a spread of Re(2)-Fe(1) bond distances ranging from 2.22-2.38 Å. Fe(1) is bonded in a single-bond geometry to four equivalent Re(2) and one Se(1) atom. The Fe(1)-Se(1) bond length is 1.16 Å. Se(1) is bonded in a single-bond geometry to four equivalent Re(1) and one Fe(1) atom.