data_FeSn2Ge
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.13
_cell_length_b   3.13
_cell_length_c   7.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   91.4
_symmetry_Int_Tables_number   1
_chemical_formula_structural   FeSn2Ge
_chemical_formula_sum   'Fe1 Sn2 Ge1'
_cell_volume   77.38
_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
  Fe  Fe0  1  0.0  0.0  0.0  1.0
  Sn  Sn2  1  0.18  0.0  0.3  1.0
  Sn  Sn3  1  0.18  0.0  0.61  1.0
  Ge  Ge1  1  0.0  0.0  0.96  1.0

data_FeSn2Ge
_symmetry_space_group_name_H-M   Pm
_cell_length_a   3.13
_cell_length_b   3.13
_cell_length_c   7.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   6
_chemical_formula_structural   FeSn2Ge
_chemical_formula_sum   'Fe1 Sn2 Ge1'
_cell_volume   77.41
_cell_formula_units_Z   1
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '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
  Fe  Fe0  1  0.0  0.0  0.0  1.0
  Sn  Sn1  1  0.18  0.0  0.3  1.0
  Sn  Sn2  1  0.18  0.0  0.61  1.0
  Ge  Ge3  1  0.0  0.0  0.96  1.0

Fe Sn Sn Ge
FeSn2Ge crystallizes in the monoclinic Pm space group. Fe(1) is bonded in a single-bond geometry to one Sn(1) and one Ge(1) atom. The Fe(1)-Sn(1) bond length is 2.47 Å. The Fe(1)-Ge(1) bond length is 0.33 Å. There are two inequivalent Sn sites. In the first Sn site, Sn(1) is bonded in a 2-coordinate geometry to one Fe(1) and one Sn(2) atom. The Sn(1)-Sn(2) bond length is 2.45 Å. In the second Sn site, Sn(2) is bonded to one Sn(1), four equivalent Sn(2), and one Ge(1) atom to form a mixture of corner and edge-sharing SnSn5Ge octahedra. The corner-sharing octahedra are not tilted. All Sn(2)-Sn(2) bond lengths are 3.13 Å. The Sn(2)-Ge(1) bond length is 2.79 Å. Ge(1) is bonded in a single-bond geometry to one Fe(1) and one Sn(2) atom.