data_Mn2FeSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.94
_cell_length_b   3.94
_cell_length_c   3.94
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mn2FeSi
_chemical_formula_sum   'Mn2 Fe1 Si1'
_cell_volume   43.12
_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
  Mn  Mn1  1  0.39  0.39  0.39  1.0
  Mn  Mn2  1  0.17  0.17  0.17  1.0
  Fe  Fe0  1  0.78  0.78  0.78  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

data_Mn2FeSi
_symmetry_space_group_name_H-M   R3m
_cell_length_a   3.94
_cell_length_b   3.94
_cell_length_c   9.64
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Mn2FeSi
_chemical_formula_sum   'Mn6 Fe3 Si3'
_cell_volume   129.35
_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
  Mn  Mn0  3  0.0  0.0  0.61  1.0
  Mn  Mn1  3  0.0  0.0  0.83  1.0
  Fe  Fe2  3  0.0  0.0  0.22  1.0
  Si  Si3  3  0.0  0.0  0.0  1.0

Mn Mn Fe Si
Mn Mn Fe Si 0 1 o o o 0 1 o o + 0 1 + o o 0 1 o + o 0 3 o o + 0 3 o + o 0 3 + o o 0 2 - o o 0 2 o - o 0 2 o o - 1 3 o o o 1 2 o - - 1 2 - o - 1 2 - - o 2 3 + o + 2 3 o + + 2 3 + + o 2 3 + + + 
Mn2FeSi crystallizes in the trigonal R3m space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 7-coordinate geometry to one Mn(2), three equivalent Fe(1), and three equivalent Si(1) atoms. The Mn(1)-Mn(2) bond length is 2.09 Å. All Mn(1)-Fe(1) bond lengths are 2.34 Å. All Mn(1)-Si(1) bond lengths are 2.34 Å. In the second Mn site, Mn(2) is bonded in a distorted single-bond geometry to one Mn(1), three equivalent Fe(1), and one Si(1) atom. All Mn(2)-Fe(1) bond lengths are 2.34 Å. The Mn(2)-Si(1) bond length is 1.68 Å. Fe(1) is bonded in a 7-coordinate geometry to three equivalent Mn(1), three equivalent Mn(2), and one Si(1) atom. The Fe(1)-Si(1) bond length is 2.09 Å. Si(1) is bonded in a distorted single-bond geometry to one Mn(2), three equivalent Mn(1), and one Fe(1) atom.