data_MgCo2Si
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.81
_cell_length_b   2.85
_cell_length_c   5.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.99
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgCo2Si
_chemical_formula_sum   'Mg1 Co2 Si1'
_cell_volume   47.46
_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  Mg2  1  0.0  0.0  0.0  1.0
  Co  Co0  1  0.34  0.43  0.23  1.0
  Co  Co1  1  0.37  0.43  0.68  1.0
  Si  Si3  1  0.95  0.0  0.96  1.0

data_MgCo2Si
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.81
_cell_length_b   2.85
_cell_length_c   5.92
_cell_angle_alpha   90.0
_cell_angle_beta   90.99
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgCo2Si
_chemical_formula_sum   'Mg1 Co2 Si1'
_cell_volume   47.46
_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  0.0  0.0  1.0
  Co  Co1  1  0.34  0.43  0.23  1.0
  Co  Co2  1  0.37  0.43  0.68  1.0
  Si  Si3  1  0.95  0.0  0.96  1.0

Mg Co Co Si
MgCo2Si crystallizes in the triclinic P1 space group. Mg(1) is bonded in a single-bond geometry to two equivalent Co(1) and one Si(1) atom. There is one shorter (2.06 Å) and one longer (2.33 Å) Mg(1)-Co(1) bond length. The Mg(1)-Si(1) bond length is 0.28 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded in a 2-coordinate geometry to two equivalent Mg(1) and one Co(2) atom. The Co(1)-Co(2) bond length is 2.67 Å. In the second Co site, Co(2) is bonded in a 9-coordinate geometry to one Co(1), four equivalent Co(2), and four equivalent Si(1) atoms. There are two shorter (2.81 Å) and two longer (2.85 Å) Co(2)-Co(2) bond lengths. There are a spread of Co(2)-Si(1) bond distances ranging from 2.36-2.80 Å. Si(1) is bonded in a single-bond geometry to one Mg(1) and four equivalent Co(2) atoms.