The crystal structure described by NpFe4Al8 crystallizes in the tetragonal I4/mmm space group. Np(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), four equivalent Al(2), and eight equivalent Al(1) atoms. Fe(1) is bonded in a 12-coordinate geometry to two equivalent Np(1), two equivalent Fe(1), four equivalent Al(1), and four equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent Np(1), four equivalent Fe(1), two equivalent Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to one Np(1), four equivalent Fe(1), one Al(2), and four equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_Np(Al2Fe)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.673
_cell_length_b   6.673
_cell_length_c   6.673
_cell_angle_alpha   98.012
_cell_angle_beta   98.012
_cell_angle_gamma   136.156
_symmetry_Int_Tables_number   1
_cell_volume   190.903
_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  Np0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.500  0.725  0.225  1.0
  Al  Al2  1  0.275  0.500  0.775  1.0
  Al  Al3  1  0.725  0.500  0.225  1.0
  Al  Al4  1  0.500  0.275  0.775  1.0
  Al  Al5  1  0.000  0.657  0.657  1.0
  Al  Al6  1  0.000  0.343  0.343  1.0
  Al  Al7  1  0.657  0.000  0.657  1.0
  Al  Al8  1  0.343  0.000  0.343  1.0
  Fe  Fe9  1  0.500  0.000  0.000  1.0
  Fe  Fe10  1  0.500  0.500  0.500  1.0
  Fe  Fe11  1  0.000  0.000  0.500  1.0
  Fe  Fe12  1  0.000  0.500  0.000  1.0
[/CIF]
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The crystal structure described by NpFe4Al8 crystallizes in the tetragonal I4/mmm space group. Np(1) is bonded in a 20-coordinate geometry to eight equivalent Fe(1), four equivalent Al(2), and eight equivalent Al(1) atoms. Fe(1) is bonded in a 12-coordinate geometry to two equivalent Np(1), two equivalent Fe(1), four equivalent Al(1), and four equivalent Al(2) atoms. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 12-coordinate geometry to two equivalent Np(1), four equivalent Fe(1), two equivalent Al(1), and four equivalent Al(2) atoms. In the second Al site, Al(2) is bonded in a 10-coordinate geometry to one Np(1), four equivalent Fe(1), one Al(2), and four equivalent Al(1) atoms. is represented by the CIF card [CIF]
data_Np(Al2Fe)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.673
_cell_length_b   6.673
_cell_length_c   6.673
_cell_angle_alpha   98.012
_cell_angle_beta   98.012
_cell_angle_gamma   136.156
_symmetry_Int_Tables_number   1
_cell_volume   190.903
_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  Np0  1  0.000  0.000  0.000  1.0
  Al  Al1  1  0.500  0.725  0.225  1.0
  Al  Al2  1  0.275  0.500  0.775  1.0
  Al  Al3  1  0.725  0.500  0.225  1.0
  Al  Al4  1  0.500  0.275  0.775  1.0
  Al  Al5  1  0.000  0.657  0.657  1.0
  Al  Al6  1  0.000  0.343  0.343  1.0
  Al  Al7  1  0.657  0.000  0.657  1.0
  Al  Al8  1  0.343  0.000  0.343  1.0
  Fe  Fe9  1  0.500  0.000  0.000  1.0
  Fe  Fe10  1  0.500  0.500  0.500  1.0
  Fe  Fe11  1  0.000  0.000  0.500  1.0
  Fe  Fe12  1  0.000  0.500  0.000  1.0
[/CIF]
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