data_FeSiP
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.87
_cell_length_b   3.87
_cell_length_c   4.99
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   FeSiP
_chemical_formula_sum   'Fe2 Si2 P2'
_cell_volume   74.73
_cell_formula_units_Z   2
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
  Fe  Fe1  1  0.93  0.93  0.0  1.0
  Si  Si4  1  0.93  0.0  0.42  1.0
  Si  Si5  1  0.0  0.93  0.58  1.0
  P  P2  1  0.93  0.0  0.67  1.0
  P  P3  1  0.0  0.93  0.33  1.0

data_FeSiP
_symmetry_space_group_name_H-M   C2/m
_cell_length_a   5.47
_cell_length_b   5.47
_cell_length_c   4.99
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   12
_chemical_formula_structural   FeSiP
_chemical_formula_sum   'Fe4 Si4 P4'
_cell_volume   149.46
_cell_formula_units_Z   4
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-x, -y, -z'
  3  '-x, y, -z'
  4  'x, -y, z'
  5  'x+1/2, y+1/2, z'
  6  '-x+1/2, -y+1/2, -z'
  7  '-x+1/2, y+1/2, -z'
  8  '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
  Fe  Fe0  4  0.0  0.03  0.0  1.0
  Si  Si1  4  0.03  0.0  0.58  1.0
  P  P2  4  0.03  0.0  0.33  1.0

Fe Fe Si Si P P
FePSi crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two iron molecules and four phosphanylidynesilicon molecules.