The CO stretch frequency of fully CO covered Ag-clusters in dependence on cluster size

Silver clusters Agn prepared either by the gas aggregation technique (GAT) or by matrix aggregation of Ag were embedded in CO and CO/Ar-matrices. The vibrational CO stretch frequency at the monolayer coverage, which is found on bulk silver at 2110 cm-1, preserves its value with decreasing particle size, Agn n≥300. For smaller clusters a decrease of this frequency with decreasing size was observed. For the smallest investigated clusters Agn, n∼30, a value of 2080 cm-1 was obtained. The weakening of the CO bond is an indication of a charge transfer from the cluster to the CO monolayer. This result is in accordance with the surface plasmon absorption measurements of Ag-clusters isolated in CO matrices

Presence of Li Clusters in Molten LiCl-Li

Molten mixtures of lithium chloride and metallic lithium are of significant interest in various metal oxide reduction processes. These solutions have been reported to exhibit seemingly anomalous physical characteristics that lack a comprehensive explanation. In the current work, the physical chemistry of molten solutions of lithium chloride and metallic lithium, with and without lithium oxide, was investigated using in situ Raman spectroscopy. The Raman spectra obtained from these solutions were in agreement with the previously reported spectrum of the lithium cluster, Li(8). This observation is indicative of a nanofluid type colloidal suspension of Li(8) in a molten salt matrix. It is suggested that the formation and suspension of lithium clusters in lithium chloride is the cause of various phenomena exhibited by these solutions that were previously unexplainable