data_[Ca4Se4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [P-1]
_cell_length_a [4.1144]
_cell_length_b [4.1144]
_cell_length_c [32.6866]
_cell_angle_alpha [90.2628]
_cell_angle_beta [90.4683]
_cell_angle_gamma [90.0276]
_symmetry_Int_Tables_number [2]
_chemical_formula_structural [CaSe]
_chemical_formula_sum '[Ca4 Se4]'
_cell_volume [553.3006]
_cell_formula_units_Z [4]
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
[
  Ca  Ca0  2  0.0449  0.3009  0.7926  1
  Ca  Ca1  2  0.4607  0.2022  0.2909  1
  Se  Se2  2  0.0388  0.2977  0.7025  1
  Se  Se3  2  0.4546  0.1989  0.2008  1
]