Calculations gold clusters

Rosch, N., Gorling, A., Ellis, D.E. and Schmidbaur, H. (1989) Aurophilicity as Concerted Effect Relativistic MO Calculations on Carbon-Centered Gold Clusters. Angewandte Chemie International Edition, 28, 1357-1359. 

Gilb, S., Weis, P., Furche, F., Ahlrichs, R. and Kappes, M.M. (2002) Structures of small gold cluster cations (Au u< 14) Ion mobility measurements versus density functional calculations. Journal of Chemical Physics, 116, 4094—4101. 

Fernandez, E.M., Soler, J.M. and Baibas, L.C. (2006) Planar and cagelike structures of gold clusters Density-functional pseudopotential calculations. Physical Review B - Condensed Matter, 73, 235433-1-235433-8. 

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... 

CO desorption from photoexcited free (carbonyl)gold clusters has been studied by photoelectron spectroscopy. For the particular example [Au2(CO)]-, the unimolecular desorption threshold has been approximated by statistical calculations using the experimentally determined rate constants.294... 

Fig. I Low-resolution ESI mass spectra of the nine fractionated gold clusters (left). The deconvolved mass spectra (right). The calculated spectra for Au (SG)m are shown by the colored peaks with the corresponding n-m values [2]...

As an additional point, the f-factors calculated for the four sites of Aujj [25], as well as those for several smaller and larger magic-number and non-magic number cuboctahedra, for most of which no real examples of gold cluster compounds exist, exhibit a linear dependence on the coordination number of each site. Several of these are shown in Fig. 5. Thus, the coordination numbers of... 

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

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. 

The nature of the bonding in heteronuclear gold cluster compounds has been investigated primarily by means of semiempirical molecular orbital calculations and the results of these studies have allowed a number of structural generalizations to be made. These theoretical developments have been discussed in detail in a series of papers by Mingos et al. (210, 256, 279-282) and only a brief description of the results of this work will be given in this section. 

There have been a number of theoretical studies of small gold clusters and their reactivity with oxygen,1,8,13-21 but because of the different DFT methodologies (see Appendix at the end of this chapter) used it is scarcely surprising that the answers are qualitatively different. Most of the calculations confirm the experimental observations, and add some gloss to them the most recent calculations agree extraordinarily well with experimental... 

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