data_NaCa3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.27
_cell_length_b   4.27
_cell_length_c   8.85
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaCa3
_chemical_formula_sum   'Na1 Ca3'
_cell_volume   161.13
_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
  Na  Na3  1  0.0  0.0  0.0  1.0
  Ca  Ca0  1  0.13  0.13  0.14  1.0
  Ca  Ca1  1  0.0  0.0  0.43  1.0
  Ca  Ca2  1  0.13  0.13  0.71  1.0

data_NaCa3
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.03
_cell_length_b   6.03
_cell_length_c   8.85
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   NaCa3
_chemical_formula_sum   'Na2 Ca6'
_cell_volume   322.25
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Na  Na0  2  0.0  0.0  0.0  1.0
  Ca  Ca1  2  0.0  0.0  0.43  1.0
  Ca  Ca2  2  0.13  0.0  0.14  1.0
  Ca  Ca3  2  0.13  0.0  0.71  1.0

Na Ca Ca Ca
Na Ca Ca Ca 0 1 o o o 0 3 o o - 1 2 o o o 2 3 o o o 