Heterogeneous Catalysis Using 26.5 eV Soft X-ray Laser

A new desk-top, 26.5 eV/photon (46.9 nm), soft x-ray (extreme ultraviolet, EUV) laser has been employed to study gas phase cluster chemistry in our group. The soft x-ray laser not only ionizes all the neutral clusters, but it is a very gentle ionization source that does not seriously fragment the metal oxide clusters (e.g. VmOn, NbmOn, and TamOn clusters), and even hydrogen bonded clusters (H2O)n, (CH3OH)n, (NH3)n, (HCOOH)n, and van der Waals (SO2)n, and (CO2)n. In studies of these weakly bound and metal oxide clusters, neutral cluster distributions obtained by 26.5 eV soft x-ray ionization are much the same as those distributions obtained with near threshold ionization by a 118 nm laser, with the exception that some oxygen rich clusters can not be ionized by the 118 nm light. The 26.5 eV, soft x-ray laser is an ideal light source with which we can detect all neutral cluster species and their reaction products