Chemistry Staff Seminar Series Seminar

Ramon Rios:  Development of new organocascade reactions

Abstract: Organocatalysis have been emerged as an amazing tool for the stereocontroled synthesis of complex structures via organocascade reactions. The easy prediction of the stereochemical outcome of the reactions and high stereoselectivities often achieved, make organocascade reactions a wise approach for the synthesis of complex structures with several stereocenters. In this seminar we will show the latest organocascades reactions developed in our research group.

Chris-Kriton Skylaris:  Density functional theory calculations with thousands of atoms

The ability to describe at the atomic level of detail the interactions between nanoscale objects, such as biomolecular assemblies or nanoparticles is required for computational simulations in important application areas such as drug optimisation and catalysis. Such nanostructures typically involve thousands of atoms, and simulations are usually performed by empirical classical force fields or with hybrid quantum/classical (QM/MM) approaches. One way to overcome the limitations of the empirical nature of force fields or the arbitrariness of QM/MM interfaces would be to simulate entire nanostructures with density functional theory (DFT) calculations. To make progress towards this goal we need to reduce the computational scaling bottleneck of conventional DFT with linear scaling DFT approaches. In this context, I will describe the linear-scaling DFT approach that is implemented in our ONETEP program. We use atom-centred orbitals throughout the calculation which are optimised with localisation constraints to allow us to perform large-scale DFT with near-complete basis set accuracy. Tests of accuracy and scaling will be provided as example calculations and I will present some of our work in the calculation of free energies of binding. I will finish with describing our recent work in developing a large-scale DFT method for metallic systems and will provide some examples of calculations on metallic nanoparticles.