data_[Mg3Mn6Ni6O18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mg  1.3100  1.5000  0.8600
  Mn  1.5500  1.4000  0.6483
  Ni  1.9100  1.3500  0.7400
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [5.1656]
_cell_length_b [5.1656]
_cell_length_c [14.8677]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [MgMn2(NiO3)2]
_chemical_formula_sum '[Mg3 Mn6 Ni6 O18]'
_cell_volume [343.5753]
_cell_formula_units_Z [3]
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
[
  Mg  Mg0  3  -0.0000  0.0000  0.5000  1
  Mn  Mn1  6  0.0000  0.0000  0.1467  1
  Ni  Ni2  6  0.0000  0.0000  0.3293  1
  O  O3  18  0.0090  0.6482  0.9115  1
]