Towards an accurate theoretical description of processes on surfaces and interfaces

Abstrakt:
Surfaces and interfaces play a key role in many industrial and natural
processes. However, their accurate theoretical description is still
rather challenging. Density functional theory (DFT), the most widely
used modelling method applied to adsorption, can lead to misleading
results when standard approximations are employed. This can be in many
situations attributed to a missing description of electron dispersion
forces. We discuss two different schemes one can use to improve
the description of dispersion within DFT. First, a so-called
van der Waals density functional (vdW-DF) of Lagreth and Lundqvist groups.
For this scheme we proposed a modification that improves its accuracy
and we show applications of the improved method to a range of systems.
Second, we discuss the random phase approximation (RPA) to
the correlation energy. This, in principle, offers higher accuracy
than vdW-DF but at a much larger computational cost. We show two
ways how to reduce the cost and discuss other issues related to
the RPA scheme.