data_FeCoSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.79
_cell_length_b   3.79
_cell_length_c   3.79
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   FeCoSi
_chemical_formula_sum   'Fe1 Co1 Si1'
_cell_volume   38.41
_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  Fe1  1  0.34  0.34  0.34  1.0
  Co  Co0  1  0.68  0.68  0.68  1.0
  Si  Si2  1  0.0  0.0  0.0  1.0

data_FeCoSi
_symmetry_space_group_name_H-M   R3m
_cell_length_a   3.79
_cell_length_b   3.79
_cell_length_c   9.28
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   FeCoSi
_chemical_formula_sum   'Fe3 Co3 Si3'
_cell_volume   115.22
_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
  Fe  Fe0  3  0.0  0.0  0.66  1.0
  Co  Co1  3  0.0  0.0  0.32  1.0
  Si  Si2  3  0.0  0.0  0.0  1.0

Fe Co Si
Fe Co Si 0 2 o o + 0 2 o + o 0 2 + o o 0 1 - o o 0 1 o - o 0 1 o o - 1 2 o + + 1 2 + o + 1 2 + + o 
FeCoSi crystallizes in the trigonal R3m space group. Fe(1) is bonded to four equivalent Co(1) and four equivalent Si(1) atoms to form distorted FeCo4Si4 hexagonal bipyramids that share corners with four equivalent Co(1)Fe4Si4 hexagonal bipyramids, corners with four equivalent Si(1)Fe4Co4 hexagonal bipyramids, edges with six equivalent Co(1)Fe4Si4 hexagonal bipyramids, edges with six equivalent Si(1)Fe4Co4 hexagonal bipyramids, and edges with twelve equivalent Fe(1)Co4Si4 hexagonal bipyramids. There are three shorter (2.19 Å) and one longer (3.14 Å) Fe(1)-Co(1) bond length. There are three shorter (2.19 Å) and one longer (3.14 Å) Fe(1)-Si(1) bond length. Co(1) is bonded to four equivalent Fe(1) and four equivalent Si(1) atoms to form distorted CoFe4Si4 hexagonal bipyramids that share corners with four equivalent Fe(1)Co4Si4 hexagonal bipyramids, corners with four equivalent Si(1)Fe4Co4 hexagonal bipyramids, edges with six equivalent Fe(1)Co4Si4 hexagonal bipyramids, edges with six equivalent Si(1)Fe4Co4 hexagonal bipyramids, and edges with twelve equivalent Co(1)Fe4Si4 hexagonal bipyramids. There are three shorter (2.19 Å) and one longer (2.99 Å) Co(1)-Si(1) bond length. Si(1) is bonded to four equivalent Fe(1) and four equivalent Co(1) atoms to form distorted SiFe4Co4 hexagonal bipyramids that share corners with four equivalent Fe(1)Co4Si4 hexagonal bipyramids, corners with four equivalent Co(1)Fe4Si4 hexagonal bipyramids, edges with six equivalent Fe(1)Co4Si4 hexagonal bipyramids, edges with six equivalent Co(1)Fe4Si4 hexagonal bipyramids, and edges with twelve equivalent Si(1)Fe4Co4 hexagonal bipyramids.