Reactions of Titanium-Carbon Cluster Cations with Acetone: New Evidence for the Stability of the Met-Cars

Reactivities of titanium-carbon clusters with acetone are investigated using a triple quadrupole mass spectrometer coupled with a laser vaporization source. Unlike the Met-Car Ti{sub 8}C{sub 12}{sup +}, the other titanium-carbon clusters studied here show some degree of chemical reactivity toward acetone. In addition to reacting via association channels, the carbon-poor cluster Ti{sub 8}C{sub 11}{sup +} is able to break the chemical bonds of acetone. It is also observed that the carbon-rich clusters Ti{sub 8}C{sub 13}{sup +} and Ti{sub 8}C{sub 14}{sup +} can undergo reactive loss of carbon, leading to the Ti{sub 8}C{sub 12}{sup +} species (Met-Car) upon interaction with the acetone reactant. These studies provide new insight into the reactivities of transition metal-carbon clusters and further evidence for the stability of Met-Cars. 10 refs., 3 figs.