data_MnSi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.87
_cell_length_b   4.87
_cell_length_c   4.87
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MnSi2
_chemical_formula_sum   'Mn2 Si4'
_cell_volume   81.53
_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
  Mn  Mn0  1  0.0  0.0  0.0  1.0
  Mn  Mn1  1  0.72  0.72  0.72  1.0
  Si  Si2  1  0.58  0.58  0.3  1.0
  Si  Si3  1  0.3  0.58  0.58  1.0
  Si  Si4  1  0.58  0.3  0.58  1.0
  Si  Si5  1  0.3  0.3  0.3  1.0

data_MnSi2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.87
_cell_length_b   4.87
_cell_length_c   11.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   MnSi2
_chemical_formula_sum   'Mn6 Si12'
_cell_volume   244.59
_cell_formula_units_Z   6
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  0.0  1.0
  Mn  Mn1  3  0.0  0.0  0.28  1.0
  Si  Si2  9  0.19  0.09  0.51  1.0
  Si  Si3  3  0.0  0.0  0.7  1.0

Mn Mn Si Si Si Si
Mn Mn Si Si Si Si 0 2 - - o 0 2 - o o 0 2 o - o 0 1 - - - 0 1 - - o 0 1 - o - 0 1 o - - 0 4 - o - 0 4 - o o 0 4 o o - 0 5 - o o 0 5 o - o 0 5 o o - 0 3 o - - 0 3 o - o 0 3 o o - 1 4 o o o 1 4 o + o 1 3 o o o 1 3 + o o 1 2 o o o 1 2 o o + 1 5 o o + 1 5 o + o 1 5 + o o 2 4 o o o 2 3 o o o 2 5 o o o 3 4 o o o 3 5 o o o 4 5 o o o 
MnSi2 crystallizes in the trigonal R3m space group. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded in a 6-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. All Mn(1)-Si(1) bond lengths are 2.94 Å. All Mn(1)-Si(2) bond lengths are 2.83 Å. In the second Mn site, Mn(2) is bonded in a 3-coordinate geometry to three equivalent Si(1) and three equivalent Si(2) atoms. All Mn(2)-Si(1) bond lengths are 2.35 Å. All Mn(2)-Si(2) bond lengths are 2.99 Å. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a 3-coordinate geometry to one Mn(1), one Mn(2), one Si(2), and two equivalent Si(1) atoms. The Si(1)-Si(2) bond length is 2.35 Å. Both Si(1)-Si(1) bond lengths are 1.36 Å. In the second Si site, Si(2) is bonded in a 9-coordinate geometry to three equivalent Mn(1), three equivalent Mn(2), and three equivalent Si(1) atoms.