The compound described by Mg2Mo3FeS8 is Spinel-derived structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one S(1), one S(3), and two equivalent S(2) atoms to form MgS4 tetrahedra that share corners with three equivalent Mo(2)S6 octahedra, corners with three equivalent Fe(1)S6 octahedra, and corners with six equivalent Mo(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 57-60°. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form MoS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mo(1)S6 octahedra, edges with two equivalent Mo(2)S6 octahedra, and edges with two equivalent Fe(1)S6 octahedra. In the second Mo site, Mo(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form MoS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Fe(1)S6 octahedra, and edges with four equivalent Mo(1)S6 octahedra. Fe(1) is bonded to two equivalent S(3) and four equivalent S(2) atoms to form FeS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mo(2)S6 octahedra, and edges with four equivalent Mo(1)S6 octahedra. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one Mo(2), and two equivalent Mo(1) atoms to form distorted SMgMo3 trigonal pyramids that share corners with three equivalent S(3)MgFeMo2 trigonal pyramids, corners with three equivalent S(1)MgMo3 trigonal pyramids, corners with six equivalent S(2)MgFeMo2 trigonal pyramids,  an edgeedge with one S(3)MgFeMo2 trigonal pyramid, and edges with two equivalent S(2)MgFeMo2 trigonal pyramids. In the second S site, S(2) is bonded to one Mg(1), one Mo(1), one Mo(2), and one Fe(1) atom to form distorted SMgFeMo2 trigonal pyramids that share corners with three equivalent S(3)MgFeMo2 trigonal pyramids, corners with three equivalent S(1)MgMo3 trigonal pyramids, corners with six equivalent S(2)MgFeMo2 trigonal pyramids,  an edgeedge with one S(2)MgFeMo2 trigonal pyramid,  an edgeedge with one S(3)MgFeMo2 trigonal pyramid, and  an edgeedge with one S(1)MgMo3 trigonal pyramid. In the third S site, S(3) is bonded to one Mg(1), two equivalent Mo(1), and one Fe(1) atom to form distorted SMgFeMo2 trigonal pyramids that share corners with three equivalent S(3)MgFeMo2 trigonal pyramids, corners with three equivalent S(1)MgMo3 trigonal pyramids, corners with six equivalent S(2)MgFeMo2 trigonal pyramids,  an edgeedge with one S(1)MgMo3 trigonal pyramid, and edges with two equivalent S(2)MgFeMo2 trigonal pyramids. is represented by the CIF file [CIF]
data_Mg2FeMo3S8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.293
_cell_length_b   7.312
_cell_length_c   7.311
_cell_angle_alpha   60.446
_cell_angle_beta   60.314
_cell_angle_gamma   60.336
_symmetry_Int_Tables_number   1
_cell_volume   277.968
_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  0.876  0.876  0.876  1.0
  Mg  Mg1  1  0.124  0.124  0.124  1.0
  Fe  Fe2  1  0.500  0.500  0.500  1.0
  Mo  Mo3  1  0.500  0.500  1.000  1.0
  Mo  Mo4  1  0.000  0.500  0.500  1.0
  Mo  Mo5  1  0.500  1.000  0.500  1.0
  S  S6  1  0.741  0.740  0.740  1.0
  S  S7  1  0.264  0.265  0.716  1.0
  S  S8  1  0.264  0.716  0.265  1.0
  S  S9  1  0.715  0.265  0.265  1.0
  S  S10  1  0.736  0.284  0.735  1.0
  S  S11  1  0.285  0.735  0.735  1.0
  S  S12  1  0.259  0.260  0.260  1.0
  S  S13  1  0.736  0.735  0.284  1.0
[/CIF]
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The compound described by Mg2Mo3FeS8 is Spinel-derived structured and crystallizes in the monoclinic C2/m space group. Mg(1) is bonded to one S(1), one S(3), and two equivalent S(2) atoms to form MgS4 tetrahedra that share corners with three equivalent Mo(2)S6 octahedra, corners with three equivalent Fe(1)S6 octahedra, and corners with six equivalent Mo(1)S6 octahedra. The corner-sharing octahedral tilt angles range from 57-60°. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to two equivalent S(1), two equivalent S(2), and two equivalent S(3) atoms to form MoS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mo(1)S6 octahedra, edges with two equivalent Mo(2)S6 octahedra, and edges with two equivalent Fe(1)S6 octahedra. In the second Mo site, Mo(2) is bonded to two equivalent S(1) and four equivalent S(2) atoms to form MoS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Fe(1)S6 octahedra, and edges with four equivalent Mo(1)S6 octahedra. Fe(1) is bonded to two equivalent S(3) and four equivalent S(2) atoms to form FeS6 octahedra that share corners with six equivalent Mg(1)S4 tetrahedra, edges with two equivalent Mo(2)S6 octahedra, and edges with four equivalent Mo(1)S6 octahedra. There are three inequivalent S sites. In the first S site, S(1) is bonded to one Mg(1), one Mo(2), and two equivalent Mo(1) atoms to form distorted SMgMo3 trigonal pyramids that share corners with three equivalent S(3)MgFeMo2 trigonal pyramids, corners with three equivalent S(1)MgMo3 trigonal pyramids, corners with six equivalent S(2)MgFeMo2 trigonal pyramids,  an edgeedge with one S(3)MgFeMo2 trigonal pyramid, and edges with two equivalent S(2)MgFeMo2 trigonal pyramids. In the second S site, S(2) is bonded to one Mg(1), one Mo(1), one Mo(2), and one Fe(1) atom to form distorted SMgFeMo2 trigonal pyramids that share corners with three equivalent S(3)MgFeMo2 trigonal pyramids, corners with three equivalent S(1)MgMo3 trigonal pyramids, corners with six equivalent S(2)MgFeMo2 trigonal pyramids,  an edgeedge with one S(2)MgFeMo2 trigonal pyramid,  an edgeedge with one S(3)MgFeMo2 trigonal pyramid, and  an edgeedge with one S(1)MgMo3 trigonal pyramid. In the third S site, S(3) is bonded to one Mg(1), two equivalent Mo(1), and one Fe(1) atom to form distorted SMgFeMo2 trigonal pyramids that share corners with three equivalent S(3)MgFeMo2 trigonal pyramids, corners with three equivalent S(1)MgMo3 trigonal pyramids, corners with six equivalent S(2)MgFeMo2 trigonal pyramids,  an edgeedge with one S(1)MgMo3 trigonal pyramid, and edges with two equivalent S(2)MgFeMo2 trigonal pyramids. is represented by the CIF file [CIF]
data_Mg2FeMo3S8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.293
_cell_length_b   7.312
_cell_length_c   7.311
_cell_angle_alpha   60.446
_cell_angle_beta   60.314
_cell_angle_gamma   60.336
_symmetry_Int_Tables_number   1
_cell_volume   277.968
_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  0.876  0.876  0.876  1.0
  Mg  Mg1  1  0.124  0.124  0.124  1.0
  Fe  Fe2  1  0.500  0.500  0.500  1.0
  Mo  Mo3  1  0.500  0.500  1.000  1.0
  Mo  Mo4  1  0.000  0.500  0.500  1.0
  Mo  Mo5  1  0.500  1.000  0.500  1.0
  S  S6  1  0.741  0.740  0.740  1.0
  S  S7  1  0.264  0.265  0.716  1.0
  S  S8  1  0.264  0.716  0.265  1.0
  S  S9  1  0.715  0.265  0.265  1.0
  S  S10  1  0.736  0.284  0.735  1.0
  S  S11  1  0.285  0.735  0.735  1.0
  S  S12  1  0.259  0.260  0.260  1.0
  S  S13  1  0.736  0.735  0.284  1.0
[/CIF]
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