The structure described by MgCo4(AsS)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 3-coordinate geometry to one Co(3), one As(1), one S(2), one S(3), and one S(4) atom. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a 5-coordinate geometry to one As(1), one As(2), one As(3), one S(1), and one S(2) atom. In the second Co site, Co(2) is bonded to one As(1), one As(3), one As(4), one S(3), and one S(4) atom to form CoAs3S2 square pyramids that share corners with two equivalent Co(3)MgAs3S2 octahedra, corners with four equivalent Co(4)As3S2 square pyramids,  a cornercorner with one As(3)Co3S tetrahedra, and  a cornercorner with one As(4)Co3S tetrahedra. The corner-sharing octahedral tilt angles are 68°. In the third Co site, Co(3) is bonded to one Mg(1), one As(1), one As(2), one As(4), one S(1), and one S(2) atom to form distorted CoMgAs3S2 octahedra that share corners with two equivalent Co(2)As3S2 square pyramids, corners with two equivalent Co(4)As3S2 square pyramids, and  a cornercorner with one As(2)Co3S tetrahedra. In the fourth Co site, Co(4) is bonded to one As(2), one As(3), one As(4), one S(3), and one S(4) atom to form distorted CoAs3S2 square pyramids that share corners with two equivalent Co(3)MgAs3S2 octahedra, corners with four equivalent Co(2)As3S2 square pyramids,  a cornercorner with one As(3)Co3S tetrahedra, and  a cornercorner with one As(4)Co3S tetrahedra. The corner-sharing octahedral tilt angles range from 68-71°. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 5-coordinate geometry to one Mg(1), one Co(1), one Co(2), one Co(3), and one S(1) atom. In the second As site, As(2) is bonded to one Co(1), one Co(3), one Co(4), and one S(2) atom to form distorted AsCo3S tetrahedra that share  a cornercorner with one Co(3)MgAs3S2 octahedra, corners with two equivalent As(3)Co3S tetrahedra, and corners with two equivalent As(4)Co3S tetrahedra. The corner-sharing octahedral tilt angles are 81°. In the third As site, As(3) is bonded to one Co(1), one Co(2), one Co(4), and one S(4) atom to form AsCo3S tetrahedra that share  a cornercorner with one Co(2)As3S2 square pyramid,  a cornercorner with one Co(4)As3S2 square pyramid, corners with two equivalent As(2)Co3S tetrahedra, and corners with two equivalent As(4)Co3S tetrahedra. In the fourth As site, As(4) is bonded to one Co(2), one Co(3), one Co(4), and one S(3) atom to form AsCo3S tetrahedra that share  a cornercorner with one Co(2)As3S2 square pyramid,  a cornercorner with one Co(4)As3S2 square pyramid, corners with two equivalent As(2)Co3S tetrahedra, and corners with two equivalent As(3)Co3S tetrahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded in a trigonal non-coplanar geometry to one Co(1), one Co(3), and one As(1) atom. In the second S site, S(2) is bonded in a distorted see-saw-like geometry to one Mg(1), one Co(1), one Co(3), and one As(2) atom. In the third S site, S(3) is bonded in a see-saw-like geometry to one Mg(1), one Co(2), one Co(4), and one As(4) atom. In the fourth S site, S(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(2), one Co(4), and one As(3) atom. is represented by the CIF card [CIF]
data_MgCo4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.559
_cell_length_b   7.329
_cell_length_c   5.646
_cell_angle_alpha   85.541
_cell_angle_beta   89.857
_cell_angle_gamma   94.149
_symmetry_Int_Tables_number   1
_cell_volume   228.682
_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  0.693  0.038  0.273  1.0
  Co  Co1  1  0.458  0.318  0.515  1.0
  Co  Co2  1  0.002  0.686  0.477  1.0
  Co  Co3  1  0.994  0.313  0.016  1.0
  Co  Co4  1  0.538  0.684  0.976  1.0
  As  As5  1  0.865  0.383  0.394  1.0
  As  As6  1  0.611  0.378  0.888  1.0
  As  As7  1  0.387  0.618  0.363  1.0
  As  As8  1  0.142  0.614  0.860  1.0
  S  S9  1  0.102  0.221  0.669  1.0
  S  S10  1  0.331  0.220  0.169  1.0
  S  S11  1  0.896  0.779  0.113  1.0
  S  S12  1  0.660  0.784  0.611  1.0
[/CIF]
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The structure described by MgCo4(AsS)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a 3-coordinate geometry to one Co(3), one As(1), one S(2), one S(3), and one S(4) atom. There are four inequivalent Co sites. In the first Co site, Co(1) is bonded in a 5-coordinate geometry to one As(1), one As(2), one As(3), one S(1), and one S(2) atom. In the second Co site, Co(2) is bonded to one As(1), one As(3), one As(4), one S(3), and one S(4) atom to form CoAs3S2 square pyramids that share corners with two equivalent Co(3)MgAs3S2 octahedra, corners with four equivalent Co(4)As3S2 square pyramids,  a cornercorner with one As(3)Co3S tetrahedra, and  a cornercorner with one As(4)Co3S tetrahedra. The corner-sharing octahedral tilt angles are 68°. In the third Co site, Co(3) is bonded to one Mg(1), one As(1), one As(2), one As(4), one S(1), and one S(2) atom to form distorted CoMgAs3S2 octahedra that share corners with two equivalent Co(2)As3S2 square pyramids, corners with two equivalent Co(4)As3S2 square pyramids, and  a cornercorner with one As(2)Co3S tetrahedra. In the fourth Co site, Co(4) is bonded to one As(2), one As(3), one As(4), one S(3), and one S(4) atom to form distorted CoAs3S2 square pyramids that share corners with two equivalent Co(3)MgAs3S2 octahedra, corners with four equivalent Co(2)As3S2 square pyramids,  a cornercorner with one As(3)Co3S tetrahedra, and  a cornercorner with one As(4)Co3S tetrahedra. The corner-sharing octahedral tilt angles range from 68-71°. There are four inequivalent As sites. In the first As site, As(1) is bonded in a 5-coordinate geometry to one Mg(1), one Co(1), one Co(2), one Co(3), and one S(1) atom. In the second As site, As(2) is bonded to one Co(1), one Co(3), one Co(4), and one S(2) atom to form distorted AsCo3S tetrahedra that share  a cornercorner with one Co(3)MgAs3S2 octahedra, corners with two equivalent As(3)Co3S tetrahedra, and corners with two equivalent As(4)Co3S tetrahedra. The corner-sharing octahedral tilt angles are 81°. In the third As site, As(3) is bonded to one Co(1), one Co(2), one Co(4), and one S(4) atom to form AsCo3S tetrahedra that share  a cornercorner with one Co(2)As3S2 square pyramid,  a cornercorner with one Co(4)As3S2 square pyramid, corners with two equivalent As(2)Co3S tetrahedra, and corners with two equivalent As(4)Co3S tetrahedra. In the fourth As site, As(4) is bonded to one Co(2), one Co(3), one Co(4), and one S(3) atom to form AsCo3S tetrahedra that share  a cornercorner with one Co(2)As3S2 square pyramid,  a cornercorner with one Co(4)As3S2 square pyramid, corners with two equivalent As(2)Co3S tetrahedra, and corners with two equivalent As(3)Co3S tetrahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded in a trigonal non-coplanar geometry to one Co(1), one Co(3), and one As(1) atom. In the second S site, S(2) is bonded in a distorted see-saw-like geometry to one Mg(1), one Co(1), one Co(3), and one As(2) atom. In the third S site, S(3) is bonded in a see-saw-like geometry to one Mg(1), one Co(2), one Co(4), and one As(4) atom. In the fourth S site, S(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Co(2), one Co(4), and one As(3) atom. is represented by the CIF card [CIF]
data_MgCo4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.559
_cell_length_b   7.329
_cell_length_c   5.646
_cell_angle_alpha   85.541
_cell_angle_beta   89.857
_cell_angle_gamma   94.149
_symmetry_Int_Tables_number   1
_cell_volume   228.682
_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  0.693  0.038  0.273  1.0
  Co  Co1  1  0.458  0.318  0.515  1.0
  Co  Co2  1  0.002  0.686  0.477  1.0
  Co  Co3  1  0.994  0.313  0.016  1.0
  Co  Co4  1  0.538  0.684  0.976  1.0
  As  As5  1  0.865  0.383  0.394  1.0
  As  As6  1  0.611  0.378  0.888  1.0
  As  As7  1  0.387  0.618  0.363  1.0
  As  As8  1  0.142  0.614  0.860  1.0
  S  S9  1  0.102  0.221  0.669  1.0
  S  S10  1  0.331  0.220  0.169  1.0
  S  S11  1  0.896  0.779  0.113  1.0
  S  S12  1  0.660  0.784  0.611  1.0
[/CIF]
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