data_NbW2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.31
_cell_length_b   5.31
_cell_length_c   5.31
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbW2
_chemical_formula_sum   'Nb2 W4'
_cell_volume   106.08
_cell_formula_units_Z   2
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
  Nb  Nb0  1  0.88  0.88  0.88  1.0
  Nb  Nb1  1  0.0  0.0  0.0  1.0
  W  W2  1  0.7  0.82  0.82  1.0
  W  W3  1  0.82  0.7  0.82  1.0
  W  W4  1  0.82  0.82  0.7  1.0
  W  W5  1  0.7  0.7  0.7  1.0

data_NbW2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.31
_cell_length_b   5.31
_cell_length_c   13.02
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   NbW2
_chemical_formula_sum   'Nb6 W12'
_cell_volume   318.23
_cell_formula_units_Z   6
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
  Nb  Nb0  3  0.0  0.0  0.0  1.0
  Nb  Nb1  3  0.0  0.0  0.12  1.0
  W  W2  9  0.08  0.04  0.22  1.0
  W  W3  3  0.0  0.0  0.3  1.0

Nb Nb W W W W
NbW2 crystallizes in the trigonal R3m space group. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded in a 4-coordinate geometry to one Nb(2), three equivalent W(1), and three equivalent W(2) atoms. The Nb(1)-Nb(2) bond length is 1.58 Å. All Nb(1)-W(1) bond lengths are 1.37 Å. All Nb(1)-W(2) bond lengths are 3.64 Å. In the second Nb site, Nb(2) is bonded in a 7-coordinate geometry to one Nb(1), three equivalent W(1), and three equivalent W(2) atoms. All Nb(2)-W(1) bond lengths are 3.06 Å. All Nb(2)-W(2) bond lengths are 3.09 Å. There are two inequivalent W sites. In the first W site, W(1) is bonded in a 5-coordinate geometry to one Nb(1), one Nb(2), one W(2), and two equivalent W(1) atoms. The W(1)-W(2) bond length is 1.12 Å. Both W(1)-W(1) bond lengths are 0.65 Å. In the second W site, W(2) is bonded in a 9-coordinate geometry to three equivalent Nb(1), three equivalent Nb(2), and three equivalent W(1) atoms.