data_Mg3OsC
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.95
_cell_length_b   4.95
_cell_length_c   4.95
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg3OsC
_chemical_formula_sum   'Mg3 Os1 C1'
_cell_volume   121.21
_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  0.47  0.0  0.47  1.0
  Mg  Mg1  1  0.47  0.47  0.0  1.0
  Mg  Mg2  1  0.0  0.47  0.47  1.0
  Os  Os3  1  0.47  0.47  0.47  1.0
  C  C4  1  0.0  0.0  0.0  1.0

data_Mg3OsC
_symmetry_space_group_name_H-M   R3m
_cell_length_a   7.0
_cell_length_b   7.0
_cell_length_c   8.57
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Mg3OsC
_chemical_formula_sum   'Mg9 Os3 C3'
_cell_volume   363.63
_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
  Mg  Mg0  9  0.02  0.51  0.98  1.0
  Os  Os1  3  0.0  0.0  0.47  1.0
  C  C2  3  0.0  0.0  0.0  1.0

Mg Mg Mg Os C
Mg Mg Mg Os C 0 3 o - o 0 3 o o o 0 4 + o + 0 4 + o o 0 4 o o + 0 4 o o o 1 3 o o - 1 3 o o o 1 4 + + o 1 4 + o o 1 4 o + o 1 4 o o o 2 3 - o o 2 3 o o o 2 4 o + + 2 4 o + o 2 4 o o + 2 4 o o o 3 4 o o o 
Mg3OsC is (Cubic) Perovskite structured and crystallizes in the trigonal R3m space group. The structure consists of three 02329_fluka atoms inside a Mg3Os framework. In the Mg3Os framework, Mg(1) is bonded in a linear geometry to two equivalent Os(1) atoms. There is one shorter (2.35 Å) and one longer (2.60 Å) Mg(1)-Os(1) bond length. Os(1) is bonded to six equivalent Mg(1) atoms to form corner-sharing OsMg6 octahedra. The corner-sharing octahedra are not tilted.