Professor Kohn's proposal is for theoretical research in the physics of solids. Principal emphasis will be on density functional theory and surface physics. A. Density functional theory (DFT) He plans to build on recent contributions by his group to DFT of excited states and of time dependent processes. In view of the very wide practical use of DFT for groundstate properties, a thorough exploration of the possibilities offered by DFT for the calculation of excited state properties and of time dependent phenomena (e.g. linear response theory) will be undertaken. B. Surface Physics He shall extend his studies of the electronic structure of metal surfaces by detailed consideration of an "exactly" soluble model system: a jellium positive background sphere of radius R with N interacting electrons. He plans to calculate and compare the energy and density by DFT, hypernetted chain theory and quantum chemical methods. A second major interest is in the dynamics of inelastic scattering of atoms from surfaces, with the emission or absorption of phonons. Here he plans to build on completed model calculations in two limits: adiabatic and anti-adiabatic corresponding to incident velocities fast or slow relative to characteristic speeds of the target atoms. His aim is a consistent and comprehensive theory. Other potential projects are Landau theory of semi-infinite systems and electronic structure of quasicrystals.
