Networks from Higher Nuclearity Systems

The absorption spectrum of this complex displayed an intense absorption at 320 nm (e = 44870 M-1 cm-1) assigned to a 5d( r ) — 6p(a) transition influenced by gold-gold interactions. This complex showed a broad emission at 520 nm by excitation in a range between 300 and 400 nm, with a lifetime of 11.6 p,s in the solid state. This emission was assigned to the S — Au interaction. 

As shown in this example, although the structure displayed a complexity not found in the previous examples, the assignment of the origin of the luminescence did not differ much from simpler sulfur-gold complexes in less aggregated systems. 

As regards the heterometals that, together with gold, form supramolecular entities, there are not very many. It would be tempting to think that the group congeners silver 

This topic will be divided into two parts according to the heterometal interacting with gold the first will focus on the luminescent supramolecular structures that contain gold and other coinage elements the second will examine those containing gold and other heterometals. 

This complex was luminescent in solution and in the solid state. In acetonitrile solution, it displayed an emission at 345 nm, by excitation at 284 nm, which is similar to that of the ligand precursor and is attributed to a fluorescent process. In the solid state, it emitted at 515 nm and the ligand precursor, [H(py)2im]BF4, at 514 nm. Consequently, the remarkable similarity between the emissions of the ligand and the metal salt in both the solid state and solution suggested a ligand-centered emission. 

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