data_Na2LaP
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.18
_cell_length_b   5.18
_cell_length_c   5.18
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2LaP
_chemical_formula_sum   'Na2 La1 P1'
_cell_volume   98.06
_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  Na1  1  0.0  0.0  0.0  1.0
  Na  Na2  1  0.49  0.49  0.49  1.0
  La  La0  1  0.83  0.83  0.83  1.0
  P  P3  1  0.66  0.66  0.66  1.0

data_Na2LaP
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.18
_cell_length_b   5.18
_cell_length_c   12.68
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Na2LaP
_chemical_formula_sum   'Na6 La3 P3'
_cell_volume   294.18
_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  3  0.0  0.0  0.0  1.0
  Na  Na1  3  0.0  0.0  0.51  1.0
  La  La2  3  0.0  0.0  0.17  1.0
  P  P3  3  0.0  0.0  0.34  1.0

Na Na La P
Na Na La P 0 2 - - - 1 3 o o o 2 3 o o o 
Na2LaP crystallizes in the trigonal R3m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one La(1) and three equivalent P(1) atoms to form NaLaP3 trigonal pyramids that share  a cornercorner with one P(1)Na4La trigonal bipyramid and corners with six equivalent Na(1)LaP3 trigonal pyramids. The Na(1)-La(1) bond length is 2.16 Å. All Na(1)-P(1) bond lengths are 2.99 Å. In the second Na site, Na(2) is bonded in a single-bond geometry to one P(1) atom. The Na(2)-P(1) bond length is 2.16 Å. La(1) is bonded in a 1-coordinate geometry to one Na(1) and one P(1) atom. The La(1)-P(1) bond length is 2.16 Å. P(1) is bonded to one Na(2), three equivalent Na(1), and one La(1) atom to form distorted PNa4La trigonal bipyramids that share corners with six equivalent P(1)Na4La trigonal bipyramids and  a cornercorner with one Na(1)LaP3 trigonal pyramid.