data_[Np3Cu2Si7]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Np  1.3600  1.7500  1.0000
  Cu  1.9000  1.3500  0.8200
  Si  1.9000  1.1000  0.5400
]
_symmetry_space_group_name_H-M [P2/m]
_cell_length_a [4.1021]
_cell_length_b [3.9852]
_cell_length_c [12.6048]
_cell_angle_alpha [90.0000]
_cell_angle_beta [99.2915]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [10]
_chemical_formula_structural [Np3Cu2Si7]
_chemical_formula_sum '[Np3 Cu2 Si7]'
_cell_volume [203.3588]
_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  2  0.1813  0.0000  0.3686  1
  Np  Np1  1  0.5000  0.5000  0.0000  1
  Si  Si2  2  0.0946  0.5000  0.1691  1
  Si  Si3  2  0.2765  0.5000  0.5499  1
  Cu  Cu4  2  0.3452  0.5000  0.7364  1
  Si  Si5  2  0.4980  0.0000  0.1697  1
  Si  Si6  1  0.0000  0.0000  0.0000  1
]