Gold clusters atomic orbitals

We conclude that the bond O2-H2 AU5 formed in the complex FA Aus is an example of a nonconventional hydrogen bond. The 5d orbital of the gold atom Au5 in three-gold cluster exhibits a lone-pair character which induces its proton acceptor ability. 

Molecular orbital calculations on different gold clusters up to 13 gold atoms lead to similar results128 130. ... 

Theoretical studies of varying sizes of neutral and anionic gold (An) and silver (Ag) clusters indicate that they exhibit an even-odd oscillation in their stability and electronic properties (Fig. 34.5) [17]. Thus, clusters which have an even number of atoms tend to be more stable in the neutral state, while those having an odd number of atoms tend to be more stable in the anionic state. Since the 6s orbital energy of Au is almost as low as 5d orbitals, the strong s-d hybridization in Au favours ID and 2D structures in the case of the gold clusters. 

The topology of the centered gold clusters can be considered to be either spherical or toroidal depending on whether the center gold atom uses a nine-orbital spherical sp d ... 

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