An investigation of the impact of alkyl spacer length of the flexible ligands and influence of shape and coordination ability of the counterions has been done on a series of five silver(I)-bis(imidazole-2-thione) coordination polymers. The five compounds, namely, and [Ag 2 L 6 Br 2 ] n (L 4 = 1,1′-(butane-1,4-diyl)bis(3methylimidazoline-2-thione) and L 6 = 1,1′-(hexane-1,4-diyl)bis(3-methylimidazoline-2-thione) have been characterized by elemental analysis, IR spectra, thermogravimetric analysis (TGA), powder X-ray diffraction, and single crystal X-ray diffraction. In the title polymers, the L 4 and L 6 ligands exhibit unprecedented coordination modes, and the Ag(I) centers adopt a range of coordination geometries. The single crystal structural analysis of the title compounds shows that polymers based on the L 4 ligand predominately adopt AgS 4 core structure which does not appear in the polymers containing L 6 ligand. The TGA experimental data reveal that these compounds start to decompose in the temperature range of 240−341 °C. All of the synthesized compounds, in particular, polymer 2, possess antibacterial activity against the selected strain of Gram-negative (Escherichia coli, Pseudomonas aeruginosa) and Gram-positive (Staphylococcus aureus, Bacillus subtilis) bacteria.
The Cu(SO(3))(4)(7-) anion, which consists of a tetrahedrally coordinated Cu(I) centre coordinated to four sulfur atoms, is able to act as a multidentate ligand in discrete and infinite supramolecular species. The slow oxidation of an aqueous solution of Na(7)Cu(SO(3))(4) yields a mixed oxidation state, 2D network of composition Na(5){[Cu(II)(H(2)O)][Cu(I)(SO(3))(4)]}·6H(2)O. The addition of Cu(II) and 2,2'-bipyridine to an aqueous Na(7)Cu(SO(3))(4) solution leads to the formation of a pentanuclear complex of composition {[Cu(II)(H(2)O)(bipy)](4)[Cu(I)(SO(3))(4)]}(+); a combination of hydrogen bonding and π-π stacking interactions leads to the generation of infinite parallel channels that are occupied by disordered nitrate anions and water molecules. A pair of Cu(SO(3))(4)(7-) anions each act as a tridentate ligand towards a single Mn(II) centre when Mn(II) ions are combined with an excess of Cu(SO(3))(4)(7-). An anionic pentanuclear complex of composition {[Cu(I)(SO(3))(4)](2)[Fe(III)(H(2)O)](3)(O)} is formed when Fe(II) is added to a Cu(+)/SO(3)(2-) solution. Hydrated ferrous [Fe(H(2)O)(6)(2+)] and sodium ions act as counterions for the complexes and are responsible for the formation of an extensive hydrogen bond network within the crystal. Magnetic susceptibility studies over the temperature range 2-300 K show that weak ferromagnetic coupling occurs within the Cu(II) containing chains of Na(5){[Cu(II)(H(2)O)][Cu(I)(SO(3))(4)]}·6H(2)O, while zero coupling exists in the pentanuclear cluster {[Cu(II)(H(2)O)(bipy)](4)[Cu(I)(SO(3))(4)]}(NO(3))·H(2)O. Weak Mn(II)-O-S-O-Mn(II) antiferromagnetic coupling occurs in Na(H(2)O)(6){[Cu(I)(SO(3))(4)][Mn(II)(H(2)O)(2)](3)}, the latter formed when Mn was in excess during synthesis. The compound, Na(3)(H(2)O)(6)[Fe(II)(H(2)O)(6)](2){[Cu(I)(SO(3))(4)](2)[Fe(III)(H(2)O)](3)(O)}·H(2)O, contained trace magnetic impurities that affected the expected magnetic behaviour.
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