data_HfMgW2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.77
_cell_length_b   2.77
_cell_length_c   9.36
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HfMgW2
_chemical_formula_sum   'Hf1 Mg1 W2'
_cell_volume   72.08
_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
  Hf  Hf0  1  0.0  0.0  0.68  1.0
  Mg  Mg1  1  0.0  0.0  0.0  1.0
  W  W2  1  0.39  0.39  0.31  1.0
  W  W3  1  0.39  0.39  0.06  1.0

data_HfMgW2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   3.92
_cell_length_b   3.92
_cell_length_c   9.36
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   HfMgW2
_chemical_formula_sum   'Hf2 Mg2 W4'
_cell_volume   144.16
_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
  Hf  Hf0  2  0.0  0.0  0.68  1.0
  Mg  Mg1  2  0.0  0.0  0.0  1.0
  W  W2  2  0.39  0.0  0.06  1.0
  W  W3  2  0.39  0.0  0.31  1.0

Hf Mg W W
Hf Mg W W 0 0 + o o 0 0 o + o 0 1 o o + 1 3 o o o 2 2 + o o 2 2 o + o 2 3 o o o 
MgHfW2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded in a 4-coordinate geometry to one Hf(1) and four equivalent W(2) atoms. The Mg(1)-Hf(1) bond length is 2.97 Å. There are a spread of Mg(1)-W(2) bond distances ranging from 1.61-2.46 Å. Hf(1) is bonded in a 6-coordinate geometry to one Mg(1), four equivalent Hf(1), and one W(1) atom. All Hf(1)-Hf(1) bond lengths are 2.77 Å. The Hf(1)-W(1) bond length is 3.83 Å. There are two inequivalent W sites. In the first W site, W(1) is bonded in a 6-coordinate geometry to one Hf(1), one W(2), and four equivalent W(1) atoms. The W(1)-W(2) bond length is 2.34 Å. All W(1)-W(1) bond lengths are 2.77 Å. In the second W site, W(2) is bonded in a 3-coordinate geometry to four equivalent Mg(1) and one W(1) atom.