data_NpAl2Fe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.5
_cell_length_b   4.5
_cell_length_c   4.5
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NpAl2Fe
_chemical_formula_sum   'Np1 Al2 Fe1'
_cell_volume   64.61
_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
  Np  Np3  1  0.18  0.18  0.18  1.0
  Al  Al0  1  0.59  0.59  0.59  1.0
  Al  Al1  1  0.78  0.78  0.78  1.0
  Fe  Fe2  1  0.0  0.0  0.0  1.0

data_NpAl2Fe
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.5
_cell_length_b   4.5
_cell_length_c   11.03
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   NpAl2Fe
_chemical_formula_sum   'Np3 Al6 Fe3'
_cell_volume   193.84
_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
  Np  Np0  3  0.0  0.0  0.82  1.0
  Al  Al1  3  0.0  0.0  0.22  1.0
  Al  Al2  3  0.0  0.0  0.41  1.0
  Fe  Fe3  3  0.0  0.0  0.0  1.0

Np Al Al Fe
NpFeAl2 crystallizes in the trigonal R3m space group. Np(1) is bonded in a distorted single-bond geometry to one Fe(1), three equivalent Al(1), and three equivalent Al(2) atoms. The Np(1)-Fe(1) bond length is 2.04 Å. All Np(1)-Al(1) bond lengths are 2.73 Å. All Np(1)-Al(2) bond lengths are 2.73 Å. Fe(1) is bonded in a 1-coordinate geometry to one Np(1), three equivalent Al(1), and four equivalent Al(2) atoms. All Fe(1)-Al(1) bond lengths are 2.73 Å. There is one shorter (2.46 Å) and three longer (2.87 Å) Fe(1)-Al(2) bond lengths. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 7-coordinate geometry to three equivalent Np(1), three equivalent Fe(1), and one Al(2) atom. The Al(1)-Al(2) bond length is 2.04 Å. In the second Al site, Al(2) is bonded in a 8-coordinate geometry to three equivalent Np(1), four equivalent Fe(1), and one Al(1) atom.