data_Ba2SnAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.78
_cell_length_b   6.78
_cell_length_c   6.78
_cell_angle_alpha   137.75
_cell_angle_beta   137.75
_cell_angle_gamma   61.29
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ba2SnAs
_chemical_formula_sum   'Ba2 Sn1 As1'
_cell_volume   139.63
_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
  Ba  Ba1  1  0.45  0.0  0.92  1.0
  Ba  Ba2  1  0.0  0.0  0.84  1.0
  Sn  Sn3  1  0.0  0.45  0.92  1.0
  As  As0  1  0.0  0.0  0.0  1.0

data_Ba2SnAs
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.89
_cell_length_b   4.89
_cell_length_c   6.78
_cell_angle_alpha   111.13
_cell_angle_beta   111.13
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ba2SnAs
_chemical_formula_sum   'Ba2 Sn1 As1'
_cell_volume   139.63
_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
  Ba  Ba0  1  0.84  0.84  0.84  1.0
  Ba  Ba1  1  0.92  0.47  0.47  1.0
  Sn  Sn2  1  0.47  0.92  0.47  1.0
  As  As3  1  0.0  0.0  0.0  1.0

Ba Ba Sn As
Ba Ba Sn As 0 2 o - - 0 2 o o o 0 2 + o + 0 3 o o + 0 3 + o + 0 1 o o o 1 3 o o + 1 2 o o o 2 3 o + + 2 3 o o + 
Ba2SnAs crystallizes in the triclinic P1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 6-coordinate geometry to one Ba(2), four equivalent Sn(1), and one As(1) atom. The Ba(1)-Ba(2) bond length is 2.64 Å. There are a spread of Ba(1)-Sn(1) bond distances ranging from 3.08-3.84 Å. The Ba(1)-As(1) bond length is 3.38 Å. In the second Ba site, Ba(2) is bonded in a distorted single-bond geometry to one Ba(1), one Sn(1), and one As(1) atom. The Ba(2)-Sn(1) bond length is 2.64 Å. The Ba(2)-As(1) bond length is 1.10 Å. Sn(1) is bonded in a 5-coordinate geometry to one Ba(2) and four equivalent Ba(1) atoms. As(1) is bonded in a single-bond geometry to one Ba(1) and one Ba(2) atom.