data_SrHfSn2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.39
_cell_length_b   5.39
_cell_length_c   5.39
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   SrHfSn2
_chemical_formula_sum   'Sr1 Hf1 Sn2'
_cell_volume   110.98
_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
  Sr  Sr3  1  0.0  0.0  0.0  1.0
  Hf  Hf0  1  0.91  0.91  0.91  1.0
  Sn  Sn1  1  0.72  0.72  0.72  1.0
  Sn  Sn2  1  0.81  0.81  0.81  1.0

data_SrHfSn2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.39
_cell_length_b   5.39
_cell_length_c   13.21
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   SrHfSn2
_chemical_formula_sum   'Sr3 Hf3 Sn6'
_cell_volume   332.95
_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
  Sr  Sr0  3  0.0  0.0  0.0  1.0
  Hf  Hf1  3  0.0  0.0  0.09  1.0
  Sn  Sn2  3  0.0  0.0  0.19  1.0
  Sn  Sn3  3  0.0  0.0  0.28  1.0

Sr Hf Sn Sn
Sr Hf Sn Sn 0 1 - - - 1 3 o o o 2 3 o o o 
SrHfSn2 crystallizes in the trigonal R3m space group. Sr(1) is bonded in a distorted single-bond geometry to one Hf(1) and three equivalent Sn(1) atoms. The Sr(1)-Hf(1) bond length is 1.23 Å. All Sr(1)-Sn(1) bond lengths are 3.20 Å. Hf(1) is bonded in a linear geometry to one Sr(1) and one Sn(2) atom. The Hf(1)-Sn(2) bond length is 1.23 Å. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded to three equivalent Sr(1) and one Sn(2) atom to form distorted corner-sharing SnSr3Sn tetrahedra. The Sn(1)-Sn(2) bond length is 1.23 Å. In the second Sn site, Sn(2) is bonded in a distorted linear geometry to one Hf(1) and one Sn(1) atom.