data_Na2Mg(CO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.25
_cell_length_b   6.25
_cell_length_c   6.25
_cell_angle_alpha   47.16
_cell_angle_beta   47.16
_cell_angle_gamma   47.16
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2Mg(CO3)2
_chemical_formula_sum   'Na2 Mg1 C2 O6'
_cell_volume   119.87
_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  Na8  1  0.0  0.0  0.34  1.0
  Na  Na9  1  0.0  0.0  0.28  1.0
  Mg  Mg10  1  0.0  0.0  0.0  1.0
  C  C0  1  0.0  0.0  0.82  1.0
  C  C1  1  0.0  0.0  0.8  1.0
  O  O2  1  0.74  0.33  0.82  1.0
  O  O3  1  0.91  0.92  0.82  1.0
  O  O4  1  0.34  0.75  0.82  1.0
  O  O5  1  0.26  0.67  0.8  1.0
  O  O6  1  0.66  0.25  0.8  1.0
  O  O7  1  0.09  0.08  0.8  1.0

data_Na2Mg(CO3)2
_symmetry_space_group_name_H-M   P1
_cell_length_a   5.0
_cell_length_b   5.0
_cell_length_c   6.25
_cell_angle_alpha   66.42
_cell_angle_beta   66.42
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2Mg(CO3)2
_chemical_formula_sum   'Na2 Mg1 C2 O6'
_cell_volume   119.87
_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  Na0  1  0.0  0.66  0.34  1.0
  Na  Na1  1  0.0  0.72  0.28  1.0
  Mg  Mg2  1  0.0  0.0  0.0  1.0
  C  C3  1  0.0  0.18  0.82  1.0
  C  C4  1  0.0  0.2  0.8  1.0
  O  O5  1  0.08  0.18  0.66  1.0
  O  O6  1  0.25  0.18  0.91  1.0
  O  O7  1  0.33  0.2  0.73  1.0
  O  O8  1  0.67  0.18  0.89  1.0
  O  O9  1  0.75  0.2  0.71  1.0
  O  O10  1  0.92  0.2  0.96  1.0

Na Na Mg C C O O O O O O