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The reaction of silver acetate and silver nitrate with the new phosphinethiosemicarbazone ligand 2-(2-(diphenylphosphino)benzylidene)-N-ethylthiosemicarbazone (HLPEt) gave rise to the complexes [Ag(LPEt)][sub4]∙2MeOH (1) and [Ag[sub2](LPEt)(HLPEt)][sub2]∙(NO3)2 (3). Slow crystallization of the mother liquors obtained from the synthesis of 1 and 3 afforded suitable crystals of [Ag[sub2](LPEt)(HLPEt)][sub2](CH[sub3]COO)[sub2]∙6MeOH (2) and [Ag[sub2](LPEt)(HLPEt)][sub2](NO[sub3])[sub2]∙2MeOH∙2H[sub2]O (4), respectively. Complexes 2 and 4 are tetranuclear silver clusters displaying a similar Ag[sub4]S[sub4]P[sub4] core, but containing different sizes, conformations for the Ag[sub4]S[sub4] metallacycles, and crystal packings. The four complexes are strongly luminescent in methanol solutions. A comparison between the emission bands of compounds 1-4 lead us to conclude that the luminescence is notably affected by the charge and the counterion of the cluster. [ABSTRACT FROM AUTHOR]

A unique case of a grid-of-mesocates sequentially assembled by supramolecular cobalt(ii) meso-helical units connected through hydrogen bonding is reported. [ABSTRACT FROM AUTHOR]

A method to modulate the strength of the superexchange coupling interaction in dinuclear helical assemblies based on the coordination preferences of the metal centres is described. [ABSTRACT FROM AUTHOR]

Abstract: The neutral single-stranded monohelicate [Pd(HL)]·2(CH3CN) (1) aggregates in the solid state to give an infinite 1D supramolecular chain through either the cooperative action of hydrogen bonding and π-stacking interactions or by aromatic π-stacking alone. [Copyright &y& Elsevier]

The ability to organize functional molecules into higher dimensional arrays with well-defined spatial relationships between the components is one of the major goals in supramolecular chemistry. We report here a new route for the preparation of supramolecular boxes, incorporating two types of metal ions: (i) alkali-metal ions, which induce the supramolecular architecture and essentially play a structural role in the final compounds; (ii) manganese(III) ions, which are redox-active systems and give functionality to the new cages. Our results evidence that the size of the cavity inside the box can be tuned depending on the alkali metal used, a characteristic that gives this new family of compounds the potential to act selectively against different substrates. These compounds behave as active catalysts for disproportionation of H2O2 or for water photolysis, but they catalyze neither catecholase reaction nor peroxidase action upon using bulky organic substrates. [ABSTRACT FROM AUTHOR]