data_Pu2NbSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.73
_cell_length_b   4.73
_cell_length_c   4.73
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Pu2NbSi
_chemical_formula_sum   'Pu2 Nb1 Si1'
_cell_volume   74.74
_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
  Pu  Pu1  1  0.67  0.67  0.67  1.0
  Pu  Pu2  1  0.02  0.02  0.02  1.0
  Nb  Nb0  1  0.34  0.34  0.34  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

data_Pu2NbSi
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.73
_cell_length_b   4.73
_cell_length_c   11.58
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Pu2NbSi
_chemical_formula_sum   'Pu6 Nb3 Si3'
_cell_volume   224.23
_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
  Pu  Pu0  3  0.0  0.0  0.33  1.0
  Pu  Pu1  3  0.0  0.0  0.98  1.0
  Nb  Nb2  3  0.0  0.0  0.66  1.0
  Si  Si3  3  0.0  0.0  0.0  1.0

Pu Pu Nb Si
Pu Pu Nb Si 0 2 o o + 0 2 o + o 0 2 + o o 0 3 o + + 0 3 + o + 0 3 + + o 0 1 o + + 0 1 + o + 0 1 + + o 1 3 o o o 1 2 o o - 1 2 o - o 1 2 - o o 2 3 o o + 2 3 o + o 2 3 + o o 
Pu2NbSi crystallizes in the trigonal R3m space group. There are two inequivalent Pu sites. In the first Pu site, Pu(1) is bonded in a 7-coordinate geometry to four equivalent Nb(1) and three equivalent Si(1) atoms. There are three shorter (2.73 Å) and one longer (3.80 Å) Pu(1)-Nb(1) bond length. All Pu(1)-Si(1) bond lengths are 2.73 Å. In the second Pu site, Pu(2) is bonded in a single-bond geometry to four equivalent Nb(1) and one Si(1) atom. There are three shorter (2.73 Å) and one longer (3.80 Å) Pu(2)-Nb(1) bond length. The Pu(2)-Si(1) bond length is 0.17 Å. Nb(1) is bonded in a 11-coordinate geometry to four equivalent Pu(1), four equivalent Pu(2), and three equivalent Si(1) atoms. All Nb(1)-Si(1) bond lengths are 2.73 Å. Si(1) is bonded in a single-bond geometry to one Pu(2), three equivalent Pu(1), and three equivalent Nb(1) atoms.