[Zurück]

F. Libisch, C. Huang, J. Chen, E Carter:
"Tackling Molecule-Surface Interactions Using Embedding Methods";
Vortrag: Density-based embedding for multiscale simulations, Lausanne, Schweiz (eingeladen); 24.03.2014 - 27.03.2014.

Quantum mechanical embedding methods allow for the theoretical description of problems that cannot be
tackled with one single ab‐initio method. We use density-based embedding methods to combine the advantages of
different techniques: a system of interest is partitioned into different parts, each described by a suitable method.
In such a way, we may treat a cluster of atoms (treated with high-level correlated wavefunction theory) embedded
in an extended periodic bulk or surface crystal (treated by density functional theory). The interaction between subsystems
is mediated by a local embedding potential. We compare different approaches to determine this potential:
(i) matching of the subsystem densities to the reference density of the entire system on the density-functional
theory level [1] or (ii) a fully self-consistent minimization of the total energy as a function of the embedding potential [2].
While the latter approach is computationally quite challenging, it considers the back-action of the embedded
cluster on the entire system. We finally present two applications: the dissociation of
oxygen molecules by an aluminum surface [3], and the hot‐electron mediated dissociation of hydrogen on a gold
surface [4]. For both cases we compare to experimental results.