data_Na4CaAl
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.3
_cell_length_b   6.3
_cell_length_c   6.3
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na4CaAl
_chemical_formula_sum   'Na4 Ca1 Al1'
_cell_volume   176.99
_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  Na2  1  0.33  0.33  0.58  1.0
  Na  Na3  1  0.33  0.58  0.33  1.0
  Na  Na4  1  0.58  0.33  0.33  1.0
  Na  Na5  1  0.58  0.58  0.58  1.0
  Ca  Ca1  1  0.23  0.23  0.23  1.0
  Al  Al0  1  0.0  0.0  0.0  1.0

data_Na4CaAl
_symmetry_space_group_name_H-M   R3m
_cell_length_a   6.3
_cell_length_b   6.3
_cell_length_c   15.44
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Na4CaAl
_chemical_formula_sum   'Na12 Ca3 Al3'
_cell_volume   530.96
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  9  0.09  0.17  0.59  1.0
  Na  Na1  3  0.0  0.0  0.42  1.0
  Ca  Ca2  3  0.0  0.0  0.77  1.0
  Al  Al3  3  0.0  0.0  0.0  1.0

Na Na Na Na Ca Al
Na4CaAl crystallizes in the trigonal R3m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 3-coordinate geometry to one Na(2), two equivalent Na(1), two equivalent Ca(1), and one Al(1) atom. The Na(1)-Na(2) bond length is 2.81 Å. Both Na(1)-Na(1) bond lengths are 1.62 Å. There is one shorter (3.01 Å) and one longer (3.54 Å) Na(1)-Ca(1) bond length. The Na(1)-Al(1) bond length is 2.97 Å. In the second Na site, Na(2) is bonded in a 6-coordinate geometry to three equivalent Na(1) and three equivalent Ca(1) atoms. All Na(2)-Ca(1) bond lengths are 3.66 Å. Ca(1) is bonded in a 10-coordinate geometry to three equivalent Na(2), six equivalent Na(1), and one Al(1) atom. The Ca(1)-Al(1) bond length is 3.52 Å. Al(1) is bonded in a 4-coordinate geometry to three equivalent Na(1) and one Ca(1) atom.