data_NaSrTa2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.56
_cell_length_b   3.56
_cell_length_c   8.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NaSrTa2
_chemical_formula_sum   'Na1 Sr1 Ta2'
_cell_volume   111.28
_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  0.0  0.9  1.0
  Sr  Sr1  1  0.78  0.78  0.02  1.0
  Ta  Ta2  1  0.0  0.0  0.6  1.0
  Ta  Ta3  1  0.78  0.78  0.65  1.0

data_NaSrTa2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.03
_cell_length_b   5.03
_cell_length_c   8.78
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   NaSrTa2
_chemical_formula_sum   'Na2 Sr2 Ta4'
_cell_volume   222.56
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.0  0.0  0.9  1.0
  Sr  Sr1  2  0.28  0.5  0.02  1.0
  Ta  Ta2  2  0.0  0.0  0.6  1.0
  Ta  Ta3  2  0.28  0.5  0.65  1.0

Na Sr Ta Ta
Na Sr Ta Ta 0 1 - - + 2 3 - - o 
NaSrTa2 crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two NaSrTa2 clusters. Na(1) is bonded in a 3-coordinate geometry to one Sr(1), one Ta(1), and one Ta(2) atom. The Na(1)-Sr(1) bond length is 1.53 Å. The Na(1)-Ta(1) bond length is 2.64 Å. The Na(1)-Ta(2) bond length is 2.49 Å. Sr(1) is bonded in a single-bond geometry to one Na(1) atom. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded in a 1-coordinate geometry to one Na(1) and one Ta(2) atom. The Ta(1)-Ta(2) bond length is 1.18 Å. In the second Ta site, Ta(2) is bonded in a distorted L-shaped geometry to one Na(1) and one Ta(1) atom.