Dr. Libor Veis: Pushing the limits of computations of strongly correlated molecules

First lecture from the series of lectures by our scientists who have done research at our institute as Heyrovsky Young Scientists.

Pushing the limits of computations of  strongly correlated molecules

RNDr. Libor Veis, Ph.D

Strongly correlated molecules, i.e. molecules with energetically quasi-degenerate or-bital levels, represent a long-standing challenge of computational chemistry. Many im-portant chemical problems with high socio-economic impact fall into this category, e.g. catalysts or high temperature superconductors. Generally, when the manifold of quasi-degenerate orbitals is small, conventional methods based on the exact diagonalization are available and routinely employed. However, when dozens of orbitals are strongly corre-lated, such as in case of multi-center transition metal complexes, the electronic structure problem is much more challenging.

In this talk, I will review our recent efforts in pushing the limits of computations of strongly correlated molecules, which are well beyond the reach of the exact diagonalization. In particular, I will briefly introduce the density matrix renormalization group (DMRG) method, one of the methods especially suitable for strongly correlated molecules and mainly its highly scalable implementation developed in our group. Furthemore, I will discuss how the missing weak correlation, which is crucial for chemical accuracy, can be accounted for by means of the adiabatic connection approach. Last but not least, I will introduce the projection-based DMRG-indensity functional theory (DFT) embed-ding, which we have recently developed with the aim of treatment of real-life (extended) problems.