Professor A.J. Downs

Research

The scope of our research takes in the synthesis and chemistry of novel inorganic and organometallic compounds, mostly of the Typical Elements but also of transition metals. The emphasis is on reactive molecular species important for their roles as reaction intermediates. The work is diverse in the practical and analytical skills employed and has relevance in areas as varied as the environment (O3 and SO2), catalysis of biologically or commercially important reactions and semiconductor and solid-state device technology.

Specific objectives include:

The investigation of processes with known or potential catalytic action, e.g. in relation to the activation of O2 or organic molecules.

The development of new materials with unusual oxidising/reducing or acid/base properties.

The development of new chemical routes and mechanistic understanding of chemical vapour deposition processes leading to thin films of metals or semiconductors.

In-depth investigation of the effects of coordinating organic units like CH3 or C2H5 to metal centres.

Experimental methods which feature prominently in our work include the following:

The use of high-vacuum, inert-atmosphere, and non-aqueous-solvent techniques.

The application of spectroscopic techniques (principally infra-red and Raman spectroscopies), typically in conjunction with matrix isolation and related approaches, to the monitoring of chemical changes, to the characterisation of new compounds, and to problems of stoicheiometry, stereochemistry and bonding.

The structural and spectroscopic characterisation of gaseous molecules by electron diffraction, and of crystalline solids at low temperatures by X-ray and neutron diffraction methods.

Recent investigations have been concerned with the formation and properties of the following: (a) metal derivatives of the ligands CO, CH3,C2H5, and O2, where interest centres on the ability of the metal centre to perturb the coordinated ligand; (b) hydrides of the Typical Elements, e.g. hydride and borane derivatives like [GaH3]n; ( and c) ozone and dioxygen and their photolytic reactions.