Structure and chemistry of SiOx (x<2) systems

The structure of SiOx materials and the chemical stability of Sin+ (n<4) species have been investigated experimentally by photoemission and X-ray absorption spectroscopy. SiOx thin films and interface systems formed by small amounts of SiOx deposited on different substrates (Cu(1 0 0), TiO2(1 1 0), Al) have been studied. Theoretical analysis based on quantum mechanical calculations and cluster models have permitted to account for the stability of the different Sin+ chemical states and for some disproportionation reactions observed under certain experimental conditions.