data_Na2PrSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.07
_cell_length_b   5.07
_cell_length_c   5.07
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2PrSi
_chemical_formula_sum   'Na2 Pr1 Si1'
_cell_volume   92.4
_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  0.79  0.79  0.79  1.0
  Na  Na1  1  0.38  0.38  0.38  1.0
  Pr  Pr2  1  0.59  0.59  0.59  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

data_Na2PrSi
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.07
_cell_length_b   5.07
_cell_length_c   12.43
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Na2PrSi
_chemical_formula_sum   'Na6 Pr3 Si3'
_cell_volume   277.21
_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  0.21  1.0
  Na  Na1  3  0.0  0.0  0.62  1.0
  Pr  Pr2  3  0.0  0.0  0.41  1.0
  Si  Si3  3  0.0  0.0  0.0  1.0

Na Na Pr Si
Na Na Pr Si 0 3 + o + 0 3 o + + 0 3 + + o 0 3 + + + 0 2 o o o 0 2 o o + 0 2 + o o 0 2 o + o 0 1 o o + 0 1 o + o 0 1 + o o 1 2 o - o 1 2 - o o 1 2 o o - 1 2 o o o 1 3 o o + 1 3 o + o 1 3 + o o 2 3 o + + 2 3 + o + 2 3 + + o 
Na2PrSi is Heusler structured and crystallizes in the trigonal R3m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 2-coordinate geometry to four equivalent Pr(1) and four equivalent Si(1) atoms. There is one shorter (2.56 Å) and three longer (3.33 Å) Na(1)-Pr(1) bond lengths. There is one shorter (2.56 Å) and three longer (3.33 Å) Na(1)-Si(1) bond lengths. In the second Na site, Na(2) is bonded to four equivalent Pr(1) and three equivalent Si(1) atoms to form a mixture of distorted edge and corner-sharing NaPr4Si3 tetrahedra. There is one shorter (2.56 Å) and three longer (3.33 Å) Na(2)-Pr(1) bond lengths. All Na(2)-Si(1) bond lengths are 2.99 Å. Pr(1) is bonded in a 11-coordinate geometry to four equivalent Na(1), four equivalent Na(2), and three equivalent Si(1) atoms. All Pr(1)-Si(1) bond lengths are 3.09 Å. Si(1) is bonded in a 10-coordinate geometry to three equivalent Na(2), four equivalent Na(1), and three equivalent Pr(1) atoms.