data_MgSiSnTe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.16
_cell_length_b   5.16
_cell_length_c   5.16
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgSiSnTe
_chemical_formula_sum   'Mg1 Si1 Sn1 Te1'
_cell_volume   96.94
_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
  Si  Si1  1  0.47  0.47  0.47  1.0
  Sn  Sn2  1  0.82  0.82  0.82  1.0
  Te  Te3  1  0.65  0.65  0.65  1.0

data_MgSiSnTe
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.16
_cell_length_b   5.16
_cell_length_c   12.63
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   MgSiSnTe
_chemical_formula_sum   'Mg3 Si3 Sn3 Te3'
_cell_volume   290.81
_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  3  0.0  0.0  0.0  1.0
  Si  Si1  3  0.0  0.0  0.53  1.0
  Sn  Sn2  3  0.0  0.0  0.18  1.0
  Te  Te3  3  0.0  0.0  0.35  1.0

Mg Si Sn Te
MgSnSiTe crystallizes in the trigonal R3m space group. Mg(1) is bonded to one Sn(1) and three equivalent Te(1) atoms to form distorted MgSnTe3 trigonal pyramids that share  a cornercorner with one Te(1)Mg3SiSn trigonal bipyramid and corners with six equivalent Mg(1)SnTe3 trigonal pyramids. The Mg(1)-Sn(1) bond length is 2.24 Å. All Mg(1)-Te(1) bond lengths are 2.99 Å. Sn(1) is bonded in a distorted linear geometry to one Mg(1) and one Te(1) atom. The Sn(1)-Te(1) bond length is 2.24 Å. Si(1) is bonded in a distorted single-bond geometry to one Te(1) atom. The Si(1)-Te(1) bond length is 2.24 Å. Te(1) is bonded to three equivalent Mg(1), one Sn(1), and one Si(1) atom to form TeMg3SiSn trigonal bipyramids that share corners with six equivalent Te(1)Mg3SiSn trigonal bipyramids and  a cornercorner with one Mg(1)SnTe3 trigonal pyramid.