data_Fe2BiSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.6
_cell_length_b   4.6
_cell_length_c   4.6
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Fe2BiSe
_chemical_formula_sum   'Fe2 Bi1 Se1'
_cell_volume   68.61
_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  Fe1  1  0.87  0.87  0.87  1.0
  Fe  Fe2  1  0.62  0.62  0.62  1.0
  Bi  Bi0  1  0.25  0.25  0.25  1.0
  Se  Se3  1  0.0  0.0  0.0  1.0

data_Fe2BiSe
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.6
_cell_length_b   4.6
_cell_length_c   11.26
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Fe2BiSe
_chemical_formula_sum   'Fe6 Bi3 Se3'
_cell_volume   205.84
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  3  0.0  0.0  0.13  1.0
  Fe  Fe1  3  0.0  0.0  0.38  1.0
  Bi  Bi2  3  0.0  0.0  0.75  1.0
  Se  Se3  3  0.0  0.0  0.0  1.0

Fe Fe Bi Se
Fe Fe Bi Se 0 3 + + + 0 1 o + o 0 1 + o o 0 1 o o + 0 1 o o o 0 2 + + o 0 2 + o + 0 2 o + + 1 2 o o + 1 2 o + o 1 2 + o o 1 3 o + + 1 3 + o + 1 3 + + o 2 3 o o o 2 3 o o + 2 3 + o o 2 3 o + o 
Fe2BiSe crystallizes in the trigonal R3m space group. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a single-bond geometry to four equivalent Fe(2), three equivalent Bi(1), and one Se(1) atom. There is one shorter (2.81 Å) and three longer (2.82 Å) Fe(1)-Fe(2) bond lengths. All Fe(1)-Bi(1) bond lengths are 2.69 Å. The Fe(1)-Se(1) bond length is 1.42 Å. In the second Fe site, Fe(2) is bonded in a 10-coordinate geometry to four equivalent Fe(1), three equivalent Bi(1), and three equivalent Se(1) atoms. All Fe(2)-Bi(1) bond lengths are 2.69 Å. All Fe(2)-Se(1) bond lengths are 2.69 Å. Bi(1) is bonded in a 10-coordinate geometry to three equivalent Fe(1), three equivalent Fe(2), and four equivalent Se(1) atoms. There is one shorter (2.81 Å) and three longer (2.82 Å) Bi(1)-Se(1) bond lengths. Se(1) is bonded in a single-bond geometry to one Fe(1), three equivalent Fe(2), and four equivalent Bi(1) atoms.