Professor Graeme Watson

My broad research aims are to develop approaches for and perform high quality atomistic and quantum mechanics simulations in the fields of solid state materials, molecular and bio-molecular chemistry. To achieve this funding from HEA, EU, EI and SFI has been secured. The group has expertise in forcefield and quantum (HF, DFT, DFT+U, TDDFT) simulations applied to materials, molecular and bio-molecular modelling.
Recent work performed on oxide thin films has developed a simulated amorphisation and crystallisation procedure which is the only methodology available for the prediction of thin film structure. Using this forcefield based approach we have studied a wide range of defects that form within supported thin films of rock salt (MgO, SrO, BaO) and fluorite (CaF2, BaF2) materials Current studies are extending our work to include TiO2 and CeO2 thin films.
Periodic density function theory has been used to study atomic and electronic structure. Recent work on adsorption at metal surfaces has investigated the adsorption of molecular at metal surfaces and shown the significance of surface relaxation and considerable difference in the properties of the group 10 metals]. Studies of oxides have included the unusual electronic structure of heavy oxides and materials with ns2 lone pairs such as those containing Pb(II), Sn(II) and Bi(III). Recently collaborative work with Prof. Egdell at Oxford University has confirmed our initial findings that the so called lone pair in formed through antibonding interactions and is hence directly related to the anion involved. This finding is contrary to current textbooks.
Also of relevance is our recent work on the atomic and electronic structure of defects at the surfaces of CeO2. These calculations, in which the structure and energetics of Ce(III) formation has been calculated for the first time from first principles (DFT+U) aim to understand the catalytic reactions that occur at the surface. Currently these studies are considering the surface dependent reactivity of CeO2 for the oxidation of CO and reduction of NO2.
Our modelling also includes bio-molecular systems. We have developed new homology models for the a1a adreoceptor and performed a series of investigations on ligand docking and dynamics. These studies have indicated that different ligands induce different conformational changes on the receptor. Such changes are large enough that the size and shape of the binding site is significantly affected. A small trial of virtual screening indicated that such changes generated by relatively small molecular dynamics simulations (2 ns) were sufficient to changes the relative scoring of ligand screened with the structures. This indicates that current rigid screening methods are likely to identify ligands which are structurally similar to those used in obtaining the target structure either by modelling or experiment.

RESEARCH CENTRES: I am also Director of Trinity Centre for High Performance Computing (TCHPC) www.tchpc.tcd.ie. This is an interdisciplinary centre for High Performance Computing research, service, support and training.