The compound described by K2MgNb2(CuS2)4 crystallizes in the monoclinic Pm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to two equivalent S(3) and two equivalent S(5) atoms. In the second K site, K(2) is bonded in a 4-coordinate geometry to one S(2), one S(4), and two equivalent S(6) atoms. Mg(1) is bonded in a 3-coordinate geometry to one Cu(2), two equivalent Cu(1), one S(1), and two equivalent S(5) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent Cu(1), one S(1), one S(3), and two equivalent S(6) atoms to form distorted corner-sharing NbCu2S4 tetrahedra. In the second Nb site, Nb(2) is bonded to two equivalent Cu(1), one S(2), one S(4), and two equivalent S(5) atoms to form distorted NbCu2S4 tetrahedra that share corners with two equivalent Nb(1)Cu2S4 tetrahedra and edges with two equivalent Cu(3)S4 tetrahedra. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 7-coordinate geometry to one Mg(1), one Nb(1), one Nb(2), one S(1), one S(2), one S(5), and one S(6) atom. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one Mg(1), one S(1), one S(3), and two equivalent S(6) atoms. In the third Cu site, Cu(3) is bonded to one S(2), one S(4), and two equivalent S(5) atoms to form CuS4 tetrahedra that share edges with two equivalent Nb(2)Cu2S4 tetrahedra. There are six inequivalent S sites. In the first S site, S(1) is bonded in a distorted pentagonal planar geometry to one Mg(1), one Nb(1), one Cu(2), and two equivalent Cu(1) atoms. In the second S site, S(2) is bonded in a distorted pentagonal planar geometry to one K(2), one Nb(2), one Cu(3), and two equivalent Cu(1) atoms. In the third S site, S(3) is bonded in a 4-coordinate geometry to two equivalent K(1), one Nb(1), and one Cu(2) atom. In the fourth S site, S(4) is bonded in a 3-coordinate geometry to one K(2), one Nb(2), and one Cu(3) atom. In the fifth S site, S(5) is bonded in a 5-coordinate geometry to one K(1), one Mg(1), one Nb(2), one Cu(1), and one Cu(3) atom. In the sixth S site, S(6) is bonded in a 4-coordinate geometry to one K(2), one Nb(1), one Cu(1), and one Cu(2) atom. is represented by the CIF file [CIF]
data_K2MgNb2(CuS2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.746
_cell_length_b   7.565
_cell_length_c   9.681
_cell_angle_alpha   90.000
_cell_angle_beta   102.968
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   410.111
_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
  K  K0  1  0.459  0.750  0.586  1.0
  K  K1  1  0.912  0.250  0.343  1.0
  Mg  Mg2  1  0.133  0.750  0.944  1.0
  Nb  Nb3  1  0.558  0.750  0.208  1.0
  Nb  Nb4  1  0.413  0.250  0.774  1.0
  Cu  Cu5  1  0.482  0.495  0.995  1.0
  Cu  Cu6  1  0.482  0.005  0.995  1.0
  Cu  Cu7  1  0.070  0.750  0.216  1.0
  Cu  Cu8  1  0.913  0.250  0.787  1.0
  S  S9  1  0.738  0.750  0.003  1.0
  S  S10  1  0.722  0.250  0.984  1.0
  S  S11  1  0.891  0.750  0.401  1.0
  S  S12  1  0.597  0.250  0.587  1.0
  S  S13  1  0.165  0.497  0.784  1.0
  S  S14  1  0.318  0.502  0.206  1.0
  S  S15  1  0.165  0.003  0.784  1.0
  S  S16  1  0.318  0.998  0.206  1.0
[/CIF]
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The compound described by K2MgNb2(CuS2)4 crystallizes in the monoclinic Pm space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to two equivalent S(3) and two equivalent S(5) atoms. In the second K site, K(2) is bonded in a 4-coordinate geometry to one S(2), one S(4), and two equivalent S(6) atoms. Mg(1) is bonded in a 3-coordinate geometry to one Cu(2), two equivalent Cu(1), one S(1), and two equivalent S(5) atoms. There are two inequivalent Nb sites. In the first Nb site, Nb(1) is bonded to two equivalent Cu(1), one S(1), one S(3), and two equivalent S(6) atoms to form distorted corner-sharing NbCu2S4 tetrahedra. In the second Nb site, Nb(2) is bonded to two equivalent Cu(1), one S(2), one S(4), and two equivalent S(5) atoms to form distorted NbCu2S4 tetrahedra that share corners with two equivalent Nb(1)Cu2S4 tetrahedra and edges with two equivalent Cu(3)S4 tetrahedra. There are three inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 7-coordinate geometry to one Mg(1), one Nb(1), one Nb(2), one S(1), one S(2), one S(5), and one S(6) atom. In the second Cu site, Cu(2) is bonded in a 5-coordinate geometry to one Mg(1), one S(1), one S(3), and two equivalent S(6) atoms. In the third Cu site, Cu(3) is bonded to one S(2), one S(4), and two equivalent S(5) atoms to form CuS4 tetrahedra that share edges with two equivalent Nb(2)Cu2S4 tetrahedra. There are six inequivalent S sites. In the first S site, S(1) is bonded in a distorted pentagonal planar geometry to one Mg(1), one Nb(1), one Cu(2), and two equivalent Cu(1) atoms. In the second S site, S(2) is bonded in a distorted pentagonal planar geometry to one K(2), one Nb(2), one Cu(3), and two equivalent Cu(1) atoms. In the third S site, S(3) is bonded in a 4-coordinate geometry to two equivalent K(1), one Nb(1), and one Cu(2) atom. In the fourth S site, S(4) is bonded in a 3-coordinate geometry to one K(2), one Nb(2), and one Cu(3) atom. In the fifth S site, S(5) is bonded in a 5-coordinate geometry to one K(1), one Mg(1), one Nb(2), one Cu(1), and one Cu(3) atom. In the sixth S site, S(6) is bonded in a 4-coordinate geometry to one K(2), one Nb(1), one Cu(1), and one Cu(2) atom. is represented by the CIF file [CIF]
data_K2MgNb2(CuS2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.746
_cell_length_b   7.565
_cell_length_c   9.681
_cell_angle_alpha   90.000
_cell_angle_beta   102.968
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   410.111
_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
  K  K0  1  0.459  0.750  0.586  1.0
  K  K1  1  0.912  0.250  0.343  1.0
  Mg  Mg2  1  0.133  0.750  0.944  1.0
  Nb  Nb3  1  0.558  0.750  0.208  1.0
  Nb  Nb4  1  0.413  0.250  0.774  1.0
  Cu  Cu5  1  0.482  0.495  0.995  1.0
  Cu  Cu6  1  0.482  0.005  0.995  1.0
  Cu  Cu7  1  0.070  0.750  0.216  1.0
  Cu  Cu8  1  0.913  0.250  0.787  1.0
  S  S9  1  0.738  0.750  0.003  1.0
  S  S10  1  0.722  0.250  0.984  1.0
  S  S11  1  0.891  0.750  0.401  1.0
  S  S12  1  0.597  0.250  0.587  1.0
  S  S13  1  0.165  0.497  0.784  1.0
  S  S14  1  0.318  0.502  0.206  1.0
  S  S15  1  0.165  0.003  0.784  1.0
  S  S16  1  0.318  0.998  0.206  1.0
[/CIF]
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