Cluster ions reactions with acetylene

F. Reactions of Carbon Cluster Ions with Acetylene.. 

The chemistry of mixed carbon- and silicon-containing cluster ions has been studied by several groups " . Parent reported the rate constants for the reactions of SiC " (n = 2-8) and Si2C (n 6) with acetylene " . In this stndy an interesting exchange of carbon atoms upon reaction of "C-labeled Si2 "C + clustes was observed (equation 24). 

A new experimental setup has recently been designed to study the chemical properties of size-selected metal clusters deposited on oxide substrates [210,211], Pd clusters have been produced by a laser evaporation source, ionized, then guided by ion optics through differentially pumped vacuum chambers and size-selected by a quadrupole mass spectrometer [210-212], The monodispersed clusters have been deposited with low kinetic energy (0,l-2eV) onto an MgO thin-film surface. The clusters-assembled materials obtained in this way exhibit peculiar activity and selectivity in the polymerization of acetylene to form benzene and aliphatic hydrocarbons [224], Figure 6 shows the temperature-programmed reaction (TPR) spectra for the cyclotrimerization of acetylene on supported Pd (1 30)... 

---