The compound described by MgTiNbS4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one S(1), one S(2), two equivalent S(3), and two equivalent S(4) atoms to form MgS6 octahedra that share corners with six equivalent Ti(1)S6 octahedra, corners with six equivalent Nb(1)S6 octahedra, edges with two equivalent Mg(1)S6 octahedra,  a faceface with one Ti(1)S6 octahedra, and  a faceface with one Nb(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. Ti(1) is bonded to one S(1), one S(4), two equivalent S(2), and two equivalent S(3) atoms to form distorted TiS6 octahedra that share corners with six equivalent Mg(1)S6 octahedra, edges with two equivalent Ti(1)S6 octahedra, edges with four equivalent Nb(1)S6 octahedra, and  a faceface with one Mg(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. Nb(1) is bonded to one S(2), one S(3), two equivalent S(1), and two equivalent S(4) atoms to form distorted NbS6 octahedra that share corners with six equivalent Mg(1)S6 octahedra, edges with two equivalent Nb(1)S6 octahedra, edges with four equivalent Ti(1)S6 octahedra, and  a faceface with one Mg(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 51-53°. There are four inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Ti(1), and two equivalent Nb(1) atoms. In the second S site, S(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Ti(1), and one Nb(1) atom. In the third S site, S(3) is bonded to two equivalent Mg(1), two equivalent Ti(1), and one Nb(1) atom to form distorted SMg2Ti2Nb trigonal bipyramids that share corners with two equivalent S(4)Mg2TiNb2 trigonal bipyramids, edges with two equivalent S(3)Mg2Ti2Nb trigonal bipyramids, and edges with three equivalent S(4)Mg2TiNb2 trigonal bipyramids. In the fourth S site, S(4) is bonded to two equivalent Mg(1), one Ti(1), and two equivalent Nb(1) atoms to form distorted SMg2TiNb2 trigonal bipyramids that share corners with two equivalent S(3)Mg2Ti2Nb trigonal bipyramids, edges with two equivalent S(4)Mg2TiNb2 trigonal bipyramids, and edges with three equivalent S(3)Mg2Ti2Nb trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgTiNbS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.413
_cell_length_b   6.997
_cell_length_c   6.954
_cell_angle_alpha   62.314
_cell_angle_beta   104.186
_cell_angle_gamma   119.194
_symmetry_Int_Tables_number   1
_cell_volume   128.332
_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  0.004  0.255  0.500  1.0
  Ti  Ti1  1  0.958  0.949  0.013  1.0
  Nb  Nb2  1  0.046  0.550  0.988  1.0
  S  S3  1  0.665  0.798  0.730  1.0
  S  S4  1  0.350  0.716  0.265  1.0
  S  S5  1  0.656  0.263  0.784  1.0
  S  S6  1  0.340  0.229  0.220  1.0
[/CIF]
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The compound described by MgTiNbS4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one S(1), one S(2), two equivalent S(3), and two equivalent S(4) atoms to form MgS6 octahedra that share corners with six equivalent Ti(1)S6 octahedra, corners with six equivalent Nb(1)S6 octahedra, edges with two equivalent Mg(1)S6 octahedra,  a faceface with one Ti(1)S6 octahedra, and  a faceface with one Nb(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. Ti(1) is bonded to one S(1), one S(4), two equivalent S(2), and two equivalent S(3) atoms to form distorted TiS6 octahedra that share corners with six equivalent Mg(1)S6 octahedra, edges with two equivalent Ti(1)S6 octahedra, edges with four equivalent Nb(1)S6 octahedra, and  a faceface with one Mg(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 49-53°. Nb(1) is bonded to one S(2), one S(3), two equivalent S(1), and two equivalent S(4) atoms to form distorted NbS6 octahedra that share corners with six equivalent Mg(1)S6 octahedra, edges with two equivalent Nb(1)S6 octahedra, edges with four equivalent Ti(1)S6 octahedra, and  a faceface with one Mg(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 51-53°. There are four inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Ti(1), and two equivalent Nb(1) atoms. In the second S site, S(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), two equivalent Ti(1), and one Nb(1) atom. In the third S site, S(3) is bonded to two equivalent Mg(1), two equivalent Ti(1), and one Nb(1) atom to form distorted SMg2Ti2Nb trigonal bipyramids that share corners with two equivalent S(4)Mg2TiNb2 trigonal bipyramids, edges with two equivalent S(3)Mg2Ti2Nb trigonal bipyramids, and edges with three equivalent S(4)Mg2TiNb2 trigonal bipyramids. In the fourth S site, S(4) is bonded to two equivalent Mg(1), one Ti(1), and two equivalent Nb(1) atoms to form distorted SMg2TiNb2 trigonal bipyramids that share corners with two equivalent S(3)Mg2Ti2Nb trigonal bipyramids, edges with two equivalent S(4)Mg2TiNb2 trigonal bipyramids, and edges with three equivalent S(3)Mg2Ti2Nb trigonal bipyramids. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgTiNbS4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.413
_cell_length_b   6.997
_cell_length_c   6.954
_cell_angle_alpha   62.314
_cell_angle_beta   104.186
_cell_angle_gamma   119.194
_symmetry_Int_Tables_number   1
_cell_volume   128.332
_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  0.004  0.255  0.500  1.0
  Ti  Ti1  1  0.958  0.949  0.013  1.0
  Nb  Nb2  1  0.046  0.550  0.988  1.0
  S  S3  1  0.665  0.798  0.730  1.0
  S  S4  1  0.350  0.716  0.265  1.0
  S  S5  1  0.656  0.263  0.784  1.0
  S  S6  1  0.340  0.229  0.220  1.0
[/CIF]
.