The material structure described by MgFe4(AsS)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent Fe(1), two equivalent As(1), two equivalent As(2), and two equivalent S(1) atoms to form distorted MgFe2As4S2 hexagonal bipyramids that share corners with four equivalent S(2)Fe3As tetrahedra and edges with four equivalent Fe(2)As3S3 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 7-coordinate geometry to one Mg(1), one As(2), two equivalent As(1), one S(2), and two equivalent S(1) atoms. In the second Fe site, Fe(2) is bonded to one As(1), two equivalent As(2), one S(1), and two equivalent S(2) atoms to form FeAs3S3 octahedra that share corners with two equivalent S(2)Fe3As tetrahedra, edges with two equivalent Mg(1)Fe2As4S2 hexagonal bipyramids, and edges with two equivalent Fe(2)As3S3 octahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 5-coordinate geometry to one Mg(1), one Fe(2), two equivalent Fe(1), and one S(1) atom. In the second As site, As(2) is bonded in a 5-coordinate geometry to one Mg(1), one Fe(1), two equivalent Fe(2), and one S(2) atom. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), two equivalent Fe(1), and one As(1) atom. In the second S site, S(2) is bonded to one Fe(1), two equivalent Fe(2), and one As(2) atom to form SFe3As tetrahedra that share corners with two equivalent Mg(1)Fe2As4S2 hexagonal bipyramids, corners with two equivalent Fe(2)As3S3 octahedra, and  an edgeedge with one S(2)Fe3As tetrahedra. The corner-sharing octahedral tilt angles range from 71-72°. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.748
_cell_length_b   5.993
_cell_length_c   6.050
_cell_angle_alpha   108.996
_cell_angle_beta   89.865
_cell_angle_gamma   89.912
_symmetry_Int_Tables_number   1
_cell_volume   197.057
_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  0.500  0.000  0.000  1.0
  Fe  Fe1  1  0.496  0.728  0.231  1.0
  Fe  Fe2  1  0.996  0.279  0.284  1.0
  Fe  Fe3  1  0.504  0.272  0.769  1.0
  Fe  Fe4  1  0.004  0.721  0.716  1.0
  As  As5  1  0.657  0.857  0.595  1.0
  As  As6  1  0.107  0.150  0.862  1.0
  As  As7  1  0.343  0.143  0.405  1.0
  As  As8  1  0.893  0.850  0.138  1.0
  S  S9  1  0.647  0.379  0.174  1.0
  S  S10  1  0.142  0.642  0.339  1.0
  S  S11  1  0.353  0.621  0.826  1.0
  S  S12  1  0.858  0.358  0.661  1.0
[/CIF]
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The material structure described by MgFe4(AsS)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent Fe(1), two equivalent As(1), two equivalent As(2), and two equivalent S(1) atoms to form distorted MgFe2As4S2 hexagonal bipyramids that share corners with four equivalent S(2)Fe3As tetrahedra and edges with four equivalent Fe(2)As3S3 octahedra. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 7-coordinate geometry to one Mg(1), one As(2), two equivalent As(1), one S(2), and two equivalent S(1) atoms. In the second Fe site, Fe(2) is bonded to one As(1), two equivalent As(2), one S(1), and two equivalent S(2) atoms to form FeAs3S3 octahedra that share corners with two equivalent S(2)Fe3As tetrahedra, edges with two equivalent Mg(1)Fe2As4S2 hexagonal bipyramids, and edges with two equivalent Fe(2)As3S3 octahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded in a 5-coordinate geometry to one Mg(1), one Fe(2), two equivalent Fe(1), and one S(1) atom. In the second As site, As(2) is bonded in a 5-coordinate geometry to one Mg(1), one Fe(1), two equivalent Fe(2), and one S(2) atom. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), two equivalent Fe(1), and one As(1) atom. In the second S site, S(2) is bonded to one Fe(1), two equivalent Fe(2), and one As(2) atom to form SFe3As tetrahedra that share corners with two equivalent Mg(1)Fe2As4S2 hexagonal bipyramids, corners with two equivalent Fe(2)As3S3 octahedra, and  an edgeedge with one S(2)Fe3As tetrahedra. The corner-sharing octahedral tilt angles range from 71-72°. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.748
_cell_length_b   5.993
_cell_length_c   6.050
_cell_angle_alpha   108.996
_cell_angle_beta   89.865
_cell_angle_gamma   89.912
_symmetry_Int_Tables_number   1
_cell_volume   197.057
_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  0.500  0.000  0.000  1.0
  Fe  Fe1  1  0.496  0.728  0.231  1.0
  Fe  Fe2  1  0.996  0.279  0.284  1.0
  Fe  Fe3  1  0.504  0.272  0.769  1.0
  Fe  Fe4  1  0.004  0.721  0.716  1.0
  As  As5  1  0.657  0.857  0.595  1.0
  As  As6  1  0.107  0.150  0.862  1.0
  As  As7  1  0.343  0.143  0.405  1.0
  As  As8  1  0.893  0.850  0.138  1.0
  S  S9  1  0.647  0.379  0.174  1.0
  S  S10  1  0.142  0.642  0.339  1.0
  S  S11  1  0.353  0.621  0.826  1.0
  S  S12  1  0.858  0.358  0.661  1.0
[/CIF]
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