Events in Physics
Nicholas Hine: Theory and Simulation of Nanomaterials with Linear-Scaling Density Functional Theory
Speaker: Nicholas Hine, Cavendish Laboratory, University of Cambridge
Electronic structure methods based on density functional theory (DFT) have been highly successful in recent years at predicting the properties of bulk materials. However, as the complexity and size of the system being studied is increased, traditional DFT methods inevitably hit a 'scaling wall' in terms of computational effort required, which rises as the cube of the number of atoms.
This would seem to preclude useful contact with experiment in the study of many nanomaterials, including nanocrystals, interfaces, proteins, and disordered molecular crystals, which require accurate calculations on systems comprising many thousands of atoms, beyond the scaling wall.
However, alternative methodologies exist, based on the density matrix rather than eigenstates, which can exploit real-space localisation to achieve linear-scaling with system size and make such calculations feasible and highly parallel. The ONETEP Linear-Scaling DFT code [1], of which I am an author, combines the benefits of linear-scaling, efficient parallelisation, and variational convergence akin to plane-wave approaches, together with a wide-ranging set of features. I will present an overview of the method and discuss a number of recent applications, including semiconductor nanorods, pigment-protein complexes, defects in metal oxides, and candidate organic photovoltaic materials.
[1]