Formation and Chemistry of Molecular Metal Nitrides

Nitrides of metals have gained great importance over the last years in fields like electronics, petroleum and aerospace. Often they are produced by powder-metallurgical processes. For many metal nitrides the classical thermodynamical approach to their formation fails, because either the diffusion process is too slow for the respective solid state reaction, or the thermodynamically stable phase of the final complex cannot be accessed. In general, most of the studies that have been carried out in the gas phase, have dealt with the reaction of macro particles with nitrogen or with the formation of nitrides on surfaces. So far, no satisfying and rigorous investigations on the gas phase formation and reactivity on a molecular level have been carried out. The group of Prof. Böhme at the department of chemistry of the York University in Toronto has developed a unique inductively coupled plasma/selected ion flow tuberiple quadrupol mass spectrometer that is ideal for investigations of the formation and the chemical reactivity of metal nitrides. The goal of the project can be separated into (i) investigation of the formation of the Nitrides and (ii) the determination of basic physical properties and gas phase ion chemistry of the successfully synthesized metal nitrides. The experimental setup provides several possible regions in which the gas-phase formation of nitrides can be investigated. The first possibility is in the cold region of the plasma. The second possibility is the region between the ICP source and the entrance into the quadrupole of the SIFT tube, in the so called q0 region, and the third possibility is the flow tube itself in which the metal ions are in thermodynamic equilibrium. The investigation of basic properties, (e.g. ionization energy, proton affinity and bond dissociation energy) and the gas phase ion chemistry and reactivity of the transition metal nitrides can be performed in the flow tube of the apparatus. First feasibility studies have been carried out and show promising results for future experiments that are planned within the framework of the Schrödinger scholarship application.