Vibrational spectroscopy of gas-phase metal-carbide clusters and nanocrystals

Neutral Ti8C12 and Ti14C13 clusters are produced in the gas phase with puls ed-nozzle laser vaporization. Infrared multiphoton excitation with a pulsed free-electron laser results in thermionic electron emission for these clus ters, and the parent molecular ions are detected. Multiphoton ionization is strongly enhanced on vibrational resonances of these clusters, making it p ossible to observe infrared resonance-enhanced multiphoton ionization spect ra. These spectra indicate C-C bonding for the "met-cars" while Ti14C13 has remarkable similarities to bulk KC.