data_Mg2MnSi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.88
_cell_length_b   3.88
_cell_length_c   4.01
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2MnSi
_chemical_formula_sum   'Mg2 Mn1 Si1'
_cell_volume   60.45
_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
  Mg  Mg0  1  0.0  0.94  0.01  1.0
  Mg  Mg1  1  0.94  0.0  0.01  1.0
  Mn  Mn2  1  0.94  0.94  0.0  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0

data_Mg2MnSi
_symmetry_space_group_name_H-M   Amm2
_cell_length_a   4.01
_cell_length_b   5.49
_cell_length_c   5.49
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   38
_chemical_formula_structural   Mg2MnSi
_chemical_formula_sum   'Mg4 Mn2 Si2'
_cell_volume   120.89
_cell_formula_units_Z   2
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, y+1/2, z+1/2'
  6  '-x, -y+1/2, z+1/2'
  7  '-x, y+1/2, z+1/2'
  8  'x, -y+1/2, z+1/2'
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
  Mg  Mg0  4  0.0  0.03  0.97  1.0
  Mn  Mn1  2  0.0  0.0  0.94  1.0
  Si  Si2  2  0.0  0.0  0.0  1.0

Mg Mg Mn Si
Mg2MnSi is alpha Po structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Mg2MnSi clusters. Mg(1) is bonded in an L-shaped geometry to one Mn(1) and one Si(1) atom. The Mg(1)-Mn(1) bond length is 0.23 Å. The Mg(1)-Si(1) bond length is 0.23 Å. Mn(1) is bonded in an L-shaped geometry to two equivalent Mg(1) atoms. Si(1) is bonded in an L-shaped geometry to two equivalent Mg(1) atoms.