The material described by MgCo4(AsS)4 crystallizes in the trigonal R3 space group. Mg(1) is bonded in a 11-coordinate geometry to one Co(2), three equivalent Co(1), one As(2), three equivalent As(1), and three equivalent S(1) atoms. There are two inequivalent Co sites. In the first Co site, Co(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 Co site, Co(2) is bonded to one Mg(1), three equivalent As(1), and three equivalent S(1) atoms to form distorted CoMgAs3S3 pentagonal bipyramids that share edges with three equivalent As(1)MgCo3S tetrahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded to one Mg(1), one Co(2), two equivalent Co(1), and one S(1) atom to form distorted AsMgCo3S tetrahedra that share corners with six equivalent As(1)MgCo3S tetrahedra, corners with two equivalent S(2)Co3As trigonal pyramids, and  an edgeedge with one Co(2)MgAs3S3 pentagonal bipyramid. In the second As site, As(2) is bonded in a 5-coordinate geometry to one Mg(1), three equivalent Co(1), and one S(2) atom. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to one Mg(1), one Co(2), two equivalent Co(1), and one As(1) atom. In the second S site, S(2) is bonded to three equivalent Co(1) and one As(2) atom to form SCo3As trigonal pyramids that share corners with six equivalent As(1)MgCo3S tetrahedra. is represented by the CIF file [CIF]
data_MgCo4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.854
_cell_length_b   5.854
_cell_length_c   5.854
_cell_angle_alpha   93.051
_cell_angle_beta   93.051
_cell_angle_gamma   86.949
_symmetry_Int_Tables_number   1
_cell_volume   199.832
_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  0.294  0.794  0.706  1.0
  Co  Co1  1  0.493  0.494  0.012  1.0
  Co  Co2  1  0.521  0.021  0.479  1.0
  Co  Co3  1  0.988  0.993  0.006  1.0
  Co  Co4  1  0.994  0.488  0.507  1.0
  As  As5  1  0.624  0.881  0.114  1.0
  As  As6  1  0.076  0.576  0.924  1.0
  As  As7  1  0.381  0.386  0.376  1.0
  As  As8  1  0.886  0.124  0.619  1.0
  S  S9  1  0.411  0.145  0.874  1.0
  S  S10  1  0.864  0.364  0.136  1.0
  S  S11  1  0.126  0.911  0.355  1.0
  S  S12  1  0.645  0.626  0.589  1.0
[/CIF]
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The material described by MgCo4(AsS)4 crystallizes in the trigonal R3 space group. Mg(1) is bonded in a 11-coordinate geometry to one Co(2), three equivalent Co(1), one As(2), three equivalent As(1), and three equivalent S(1) atoms. There are two inequivalent Co sites. In the first Co site, Co(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 Co site, Co(2) is bonded to one Mg(1), three equivalent As(1), and three equivalent S(1) atoms to form distorted CoMgAs3S3 pentagonal bipyramids that share edges with three equivalent As(1)MgCo3S tetrahedra. There are two inequivalent As sites. In the first As site, As(1) is bonded to one Mg(1), one Co(2), two equivalent Co(1), and one S(1) atom to form distorted AsMgCo3S tetrahedra that share corners with six equivalent As(1)MgCo3S tetrahedra, corners with two equivalent S(2)Co3As trigonal pyramids, and  an edgeedge with one Co(2)MgAs3S3 pentagonal bipyramid. In the second As site, As(2) is bonded in a 5-coordinate geometry to one Mg(1), three equivalent Co(1), and one S(2) atom. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 5-coordinate geometry to one Mg(1), one Co(2), two equivalent Co(1), and one As(1) atom. In the second S site, S(2) is bonded to three equivalent Co(1) and one As(2) atom to form SCo3As trigonal pyramids that share corners with six equivalent As(1)MgCo3S tetrahedra. is represented by the CIF file [CIF]
data_MgCo4(AsS)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.854
_cell_length_b   5.854
_cell_length_c   5.854
_cell_angle_alpha   93.051
_cell_angle_beta   93.051
_cell_angle_gamma   86.949
_symmetry_Int_Tables_number   1
_cell_volume   199.832
_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  0.294  0.794  0.706  1.0
  Co  Co1  1  0.493  0.494  0.012  1.0
  Co  Co2  1  0.521  0.021  0.479  1.0
  Co  Co3  1  0.988  0.993  0.006  1.0
  Co  Co4  1  0.994  0.488  0.507  1.0
  As  As5  1  0.624  0.881  0.114  1.0
  As  As6  1  0.076  0.576  0.924  1.0
  As  As7  1  0.381  0.386  0.376  1.0
  As  As8  1  0.886  0.124  0.619  1.0
  S  S9  1  0.411  0.145  0.874  1.0
  S  S10  1  0.864  0.364  0.136  1.0
  S  S11  1  0.126  0.911  0.355  1.0
  S  S12  1  0.645  0.626  0.589  1.0
[/CIF]
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