data_CaFe2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.99
_cell_length_b   4.99
_cell_length_c   4.99
_cell_angle_alpha   140.72
_cell_angle_beta   121.09
_cell_angle_gamma   73.12
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaFe2Si
_chemical_formula_sum   'Ca1 Fe2 Si1'
_cell_volume   65.83
_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  Ca0  1  0.0  0.0  0.01  1.0
  Fe  Fe1  1  0.0  0.45  0.43  1.0
  Fe  Fe2  1  0.68  0.0  0.57  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

data_CaFe2Si
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.35
_cell_length_b   4.9
_cell_length_c   4.99
_cell_angle_alpha   119.46
_cell_angle_beta   109.64
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CaFe2Si
_chemical_formula_sum   'Ca1 Fe2 Si1'
_cell_volume   65.83
_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  Ca0  1  0.0  0.01  0.01  1.0
  Fe  Fe1  1  0.0  0.57  0.9  1.0
  Fe  Fe2  1  0.55  0.98  0.98  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

Ca Fe Fe Si
CaFe2Si crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one CaFe2Si cluster. Ca(1) is bonded in a single-bond geometry to one Fe(1) and one Si(1) atom. The Ca(1)-Fe(1) bond length is 1.48 Å. The Ca(1)-Si(1) bond length is 0.03 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted single-bond geometry to one Ca(1) atom. In the second Fe site, Fe(2) is bonded in a 1-coordinate geometry to one Si(1) atom. The Fe(2)-Si(1) bond length is 1.89 Å. Si(1) is bonded in a single-bond geometry to one Ca(1) and one Fe(2) atom.