Speaker
Description
Strong correlation referes to electron correlation effects inadequately described by DFT and single-reference methods like Coupled-Clusters. Examples for such systems are dissociation fragments (chemical bond breaking)[1] and partially occupied close-degenerate orbitals, for example in transition metals. Accurate treatment is possible by wave function based multi-reference methods, but computationally demanding.
With the aim of systematic improvement of existing method, strong correlation effects are investigated by application of Quantum Information Theory (QIT), which is able to quantify contributions of orbitals to electron correlation. Calculations are performed using the ab initio Density Matrix Renormalization Group (DMRG), which allows of large, strongly correlated systems.
[1] C. Stemmle, Ö. Legeza and B. Paulus, (accepted PRA)