Gold clusters features

The details given above gather the features that the nonconventional N-H- -Au bond formed between adenine and the triangle three-gold cluster shares with the conventional ones. In these bonds, the nitrogen atom of adenine is a H-bond donor and Au plays a role of a nonconventional H-bond acceptor. 

This comparison ends up the introductory part of the review. In the next sections, we discuss the main features of the nonconventional H-bond forming between gold and water clusters. In particular, the following questions are addressed in the next section What is the fate of the intramolecular H-bond of the water dimer when the latter interacts with a gold cluster, say, a triangular gold cluster Au3 [101], chosen as the simplest catalytic model of Au particles (see [103] and references therein) Is the water dimer capable of anchoring Au3, by itself an important issue in molecular electronics (see [104] and references therein) ... 

The choice of a triangular gold cluster, Au3Z, a few angstroms of size, is motivated by the fact that it can be considered as the simplest reference model of gold nanoparticles that demonstrates their exceptional catalytic features [ [14,18]a-b]. We hereby partly cover the gap between the gold atom and the gold surface, rather on the former side. 

The following features of centered gold clusters make their systematics very different from other metal cluster compounds such as metal carbonyl clusters ... 

The spectroscopic and crystallographic studies on the new osmium-gold clusters described here show a number of interesting features. 

Of the many gold cluster compounds in which the metal has an oxidation state between 0 and +1, only very few also feature bonds between gold and carbon . A recent example is the neutral cluster [Auio(C6F5)4(PPh3)5], prepared selectively by the reaction of [Au9(PPh3)g](N03)3 with [NBu4][Au(C6F5)2] in a 1 3 molar ratio . 

Because of the uncertainty surrounding TEM images of these smallest nanoclusters, other methods for obtaining particle size information were applied to the sol. The optical extinction in the ultraviolet-visible region of the spectrum (UV-vis) shows a trace of the plasmon feature typical of gold colloids, strongly suppressed due to finite-size effects [3] (Fig. 2, curve A). The spectrum resembles that of other gold cluster systems estimated at about 2 nm mean diameter [4], 1-2 nm [5] and about 1.2 run [6]. 

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