data_Ca2SnAs
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.86
_cell_length_b   3.86
_cell_length_c   7.08
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Ca2SnAs
_chemical_formula_sum   'Ca2 Sn1 As1'
_cell_volume   105.36
_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
  Ca  Ca1  1  0.93  0.93  0.55  1.0
  Ca  Ca2  1  0.93  0.93  0.53  1.0
  Sn  Sn3  1  0.0  0.0  0.54  1.0
  As  As0  1  0.0  0.0  0.0  1.0

data_Ca2SnAs
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.45
_cell_length_b   5.45
_cell_length_c   7.08
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Ca2SnAs
_chemical_formula_sum   'Ca4 Sn2 As2'
_cell_volume   210.71
_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
  Ca  Ca0  2  0.43  0.5  0.53  1.0
  Ca  Ca1  2  0.43  0.5  0.55  1.0
  Sn  Sn2  2  0.0  0.0  0.54  1.0
  As  As3  2  0.0  0.0  0.0  1.0

Ca Ca Sn As
Ca2SnAs crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Ca2SnAs clusters. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a distorted L-shaped geometry to one Ca(2), one Sn(1), and one As(1) atom. The Ca(1)-Ca(2) bond length is 0.16 Å. The Ca(1)-Sn(1) bond length is 0.40 Å. The Ca(1)-As(1) bond length is 3.19 Å. In the second Ca site, Ca(2) is bonded in a distorted L-shaped geometry to one Ca(1) and one Sn(1) atom. The Ca(2)-Sn(1) bond length is 0.40 Å. Sn(1) is bonded in a 2-coordinate geometry to one Ca(1) and one Ca(2) atom. As(1) is bonded in a single-bond geometry to one Ca(1) atom.