Professor Refson's research interests encompass both the development of density-functional theory (DFT) -based techniques for computer simulation of materials, and the application of those techniques to materials science. He is a lead developer of CASTEP, the UK's world-class plane-wave DFT materials modelling computer program, widely used on supercomputers across the UK and worldwide. His wide portfolio of research topics include studies of transport in materials for batteries and other energy-related applications, complex magnetic systems and strongly correlated electrons, phonon spectroscopy, and defects in spin-ice pyrochlore oxides. He is a member of the UK Car-Parrinello consortium, to exploit cutting-edge supercomputers (including ARCHER) for materials simulation.
He has a joint appointment with the ISIS spallation neutron facility at the Rutherford Appleton Laboratory. There he leads a programme exploiting the synergies between simulations and experiment, with a particular focus on vibrational spectroscopy and magnetic systems.