data_Ba2WSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.76
_cell_length_b   4.76
_cell_length_c   6.79
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ba2WSe
_chemical_formula_sum   'Ba2 W1 Se1'
_cell_volume   153.67
_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
  Ba  Ba0  1  0.0  0.0  0.39  1.0
  Ba  Ba1  1  0.38  0.38  0.0  1.0
  W  W3  1  0.38  0.38  0.39  1.0
  Se  Se2  1  0.0  0.0  0.0  1.0

data_Ba2WSe
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.73
_cell_length_b   6.73
_cell_length_c   6.79
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Ba2WSe
_chemical_formula_sum   'Ba4 W2 Se2'
_cell_volume   307.35
_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
  Ba  Ba0  2  0.0  0.0  0.39  1.0
  Ba  Ba1  2  0.38  0.0  0.0  1.0
  W  W2  2  0.38  0.0  0.39  1.0
  Se  Se3  2  0.0  0.0  0.0  1.0

Ba Ba W Se
Ba2WSe crystallizes in the monoclinic Cm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 2-coordinate geometry to four equivalent W(1) and one Se(1) atom. There are a spread of Ba(1)-W(1) bond distances ranging from 2.55-4.18 Å. The Ba(1)-Se(1) bond length is 2.67 Å. In the second Ba site, Ba(2) is bonded in a 5-coordinate geometry to two equivalent W(1) and three equivalent Se(1) atoms. There is one shorter (2.67 Å) and one longer (4.12 Å) Ba(2)-W(1) bond length. There is one shorter (2.55 Å) and two longer (3.46 Å) Ba(2)-Se(1) bond lengths. W(1) is bonded in a 6-coordinate geometry to two equivalent Ba(2) and four equivalent Ba(1) atoms. Se(1) is bonded in a distorted rectangular see-saw-like geometry to one Ba(1) and three equivalent Ba(2) atoms.