Neutral gold clusters

Li, G.P. and Hamilton, LP. (2006) Complexes of small neutral gold clusters and hydrogen sulphide A theoretical study. Chemical Physics Letters, 420, 474 79. 

Figure 2. Left equilibrium geometries of the two lowest energy isomeric states of Au clusters obtained using LDA or GGA scalar relativistic pseudo-potentials. The ground state is Au for GGA and Auj for LDA (except for n=6, which LDA structure is also Aue). Right difference in the binding energy per atom of the planar and 3D structures given in the left panel for neutral gold clusters with 6

Gold is one of the least reactive metals in bulk form. However, in recent years a considerable amount of theoretical and experimental works have studied the reactivity of small neutral and charged Au clusters towards different molecules, like H2, O2, CO, and organic radicals " . The reactivity depends on the size and charge state of the cluster. In the previous section we have studied the reactivity towards oxygen adsorption of anionic silver and gold clusters. In this section we study the reactivity of neutral gold clusters towards molecular O2 (subsection 6.1) and CO (subsection 6.2). 

This is a difference between the results for the ground-state structure on the PES of the neutral gold cluster of seven atoms, presented in Refs. [14,44] and this work. Note that in Ref. [14], Au was predicted to be the global minimum. 

DF calculations were carried out on CO complexes of small neutral, cationic, and anionic gold clusters Au with n= 1-6. The -coordination mode (terminal C-coordination) was found to be the most favorable one irrespective of the charge of the cluster, and cluster planarity is more stable for the bare clusters and their carbonyls. As expected, adsorption energies are greatest for the cationic clusters, and decrease with size. Instead, the adsorption energies of... 

With respect to CO adsorption on neutral Aun clusters, our preliminary results show differences with previous calculations using cluster geometries extracted from the fee gold crystal. The adsorption energy of CO is minimum for the planar magic cluster Aue and shows maxima for the odd electron clusters Au5 and Au7, both with the CO absorbed on a bridge position, but the even-odd effect is not obtained for sizes larger than n=7. 

For a recent review on small gold clusters see Ref. [33] and Ref. [34] for the 2D-3D coexistence in small neutral and charged gold clusters. 

The neutral Au9 cluster [Au9 P(C6Hn)3 5(SCN)3] has structure (109), again based on the centred icosahedron but with different gold atoms missing compared to (107). It was prepared by reduction of [Au(SCN) P(C6Hu)3 ] with borohydride.688... 

It is possible to synthesize mixed-metal clusters containing Au(PR3) fragments by treating neutral as well as anionic precursors with either [Au(PR3)]+ or a compound that acts as a source of this cation. In many cases, a [Au(PR3)]+ unit is simply added to the cluster precursor to afford a cationic heteronuclear gold cluster (e.g., 59,62-66). Equation (27)... 

Bonding Patterns that Neutral and Charged Gold Clusters form with Small Ammonia Clusters and which implement Quantum Logic Gates... 

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