The compound described by Rb4MgTi2(CuS2)4 crystallizes in the monoclinic P2/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a distorted body-centered cubic geometry to eight equivalent S(2) atoms. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to one Mg(1) and four equivalent S(1) atoms. Mg(1) is bonded to two equivalent Rb(2) and four equivalent S(1) atoms to form MgRb2S4 octahedra that share corners with four equivalent Ti(1)S4 tetrahedra, corners with four equivalent Cu(2)S4 tetrahedra, and edges with two equivalent Cu(1)S4 tetrahedra. Ti(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form TiS4 tetrahedra that share corners with two equivalent Mg(1)Rb2S4 octahedra, edges with two equivalent Cu(1)S4 tetrahedra, and edges with two equivalent Cu(2)S4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with four equivalent Cu(2)S4 tetrahedra,  an edgeedge with one Mg(1)Rb2S4 octahedra, and edges with two equivalent Ti(1)S4 tetrahedra. In the second Cu site, Cu(2) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with two equivalent Mg(1)Rb2S4 octahedra, corners with four equivalent Cu(1)S4 tetrahedra, and edges with two equivalent Ti(1)S4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 6-coordinate geometry to two equivalent Rb(2), one Mg(1), one Ti(1), one Cu(1), and one Cu(2) atom. In the second S site, S(2) is bonded in a 7-coordinate geometry to four equivalent Rb(1), one Ti(1), one Cu(1), and one Cu(2) atom. is represented by the CIF file [CIF]
data_Rb4MgTi2(CuS2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.913
_cell_length_b   5.788
_cell_length_c   13.405
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   83.848
_symmetry_Int_Tables_number   1
_cell_volume   456.121
_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
  Rb  Rb0  1  0.759  0.760  0.000  1.0
  Rb  Rb1  1  0.312  0.840  0.500  1.0
  Rb  Rb2  1  0.688  0.160  0.500  1.0
  Rb  Rb3  1  0.241  0.240  0.000  1.0
  Mg  Mg4  1  0.000  0.500  0.500  1.0
  Ti  Ti5  1  0.500  0.500  0.754  1.0
  Ti  Ti6  1  0.500  0.500  0.246  1.0
  Cu  Cu7  1  0.000  0.500  0.755  1.0
  Cu  Cu8  1  0.500  0.000  0.755  1.0
  Cu  Cu9  1  0.000  0.500  0.245  1.0
  Cu  Cu10  1  0.500  0.000  0.245  1.0
  S  S11  1  0.727  0.715  0.655  1.0
  S  S12  1  0.273  0.285  0.655  1.0
  S  S13  1  0.727  0.715  0.345  1.0
  S  S14  1  0.746  0.252  0.156  1.0
  S  S15  1  0.254  0.748  0.844  1.0
  S  S16  1  0.273  0.285  0.345  1.0
  S  S17  1  0.254  0.748  0.156  1.0
  S  S18  1  0.746  0.252  0.844  1.0
[/CIF]
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The compound described by Rb4MgTi2(CuS2)4 crystallizes in the monoclinic P2/m space group. There are two inequivalent Rb sites. In the first Rb site, Rb(1) is bonded in a distorted body-centered cubic geometry to eight equivalent S(2) atoms. In the second Rb site, Rb(2) is bonded in a 5-coordinate geometry to one Mg(1) and four equivalent S(1) atoms. Mg(1) is bonded to two equivalent Rb(2) and four equivalent S(1) atoms to form MgRb2S4 octahedra that share corners with four equivalent Ti(1)S4 tetrahedra, corners with four equivalent Cu(2)S4 tetrahedra, and edges with two equivalent Cu(1)S4 tetrahedra. Ti(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form TiS4 tetrahedra that share corners with two equivalent Mg(1)Rb2S4 octahedra, edges with two equivalent Cu(1)S4 tetrahedra, and edges with two equivalent Cu(2)S4 tetrahedra. The corner-sharing octahedral tilt angles are 59°. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with four equivalent Cu(2)S4 tetrahedra,  an edgeedge with one Mg(1)Rb2S4 octahedra, and edges with two equivalent Ti(1)S4 tetrahedra. In the second Cu site, Cu(2) is bonded to two equivalent S(1) and two equivalent S(2) atoms to form distorted CuS4 tetrahedra that share corners with two equivalent Mg(1)Rb2S4 octahedra, corners with four equivalent Cu(1)S4 tetrahedra, and edges with two equivalent Ti(1)S4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 6-coordinate geometry to two equivalent Rb(2), one Mg(1), one Ti(1), one Cu(1), and one Cu(2) atom. In the second S site, S(2) is bonded in a 7-coordinate geometry to four equivalent Rb(1), one Ti(1), one Cu(1), and one Cu(2) atom. is represented by the CIF file [CIF]
data_Rb4MgTi2(CuS2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.913
_cell_length_b   5.788
_cell_length_c   13.405
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   83.848
_symmetry_Int_Tables_number   1
_cell_volume   456.121
_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
  Rb  Rb0  1  0.759  0.760  0.000  1.0
  Rb  Rb1  1  0.312  0.840  0.500  1.0
  Rb  Rb2  1  0.688  0.160  0.500  1.0
  Rb  Rb3  1  0.241  0.240  0.000  1.0
  Mg  Mg4  1  0.000  0.500  0.500  1.0
  Ti  Ti5  1  0.500  0.500  0.754  1.0
  Ti  Ti6  1  0.500  0.500  0.246  1.0
  Cu  Cu7  1  0.000  0.500  0.755  1.0
  Cu  Cu8  1  0.500  0.000  0.755  1.0
  Cu  Cu9  1  0.000  0.500  0.245  1.0
  Cu  Cu10  1  0.500  0.000  0.245  1.0
  S  S11  1  0.727  0.715  0.655  1.0
  S  S12  1  0.273  0.285  0.655  1.0
  S  S13  1  0.727  0.715  0.345  1.0
  S  S14  1  0.746  0.252  0.156  1.0
  S  S15  1  0.254  0.748  0.844  1.0
  S  S16  1  0.273  0.285  0.345  1.0
  S  S17  1  0.254  0.748  0.156  1.0
  S  S18  1  0.746  0.252  0.844  1.0
[/CIF]
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