Name: Tobias Risthaus
Diploma / M.Sc degree: Westfälische Wilhelms-Universität Münster, Germany
(October 2010)

PhD Project: New hybrid methods for the investigation of solvent effects


Homepage: http://www.uni-muenster.de/Chemie.oc/grimme/group/index.html

Abstract of Research Project

Due to the high computational cost, conventional quantum chemistry is usually only applied to gas phase systems of limited size. Semi-empirical and force field methods are able to describe much larger systems including solvation, but they are less accurate and constrained to few applications due to the necessarily system-dependent parametrization. QM/MM methods attempt to circumvent this dilemma by the use of a unifying approach. Until recently, modern high-level DFT methods have not been used in such investigations, although the low-level DFT methods that were used instead may lack the appropriate precision. For instance, few investigations attempt to correctly describe van-der-Waals interactions that are extremely important for condensed-phase systems.

The objective of my PhD project is to attain a new level of accuracy in QM/QM/MM calculations. This will be made possible by combining a new method called VDW3, which joins inherent advantages of semi-empirical and force field methods, with double hybrid density functionals. These methods will be used for the solvation shell and the reactive species, respectively. This approach enables an investigation on the influence of solvents on energetic and selectivity aspects of reactions, starting with simple nucleophilic substitutions and, later on, electrophilic aromatic substitutions. Ultimately, a reliable and routine application of explicit solvation in QM calculations is intended.



Publications

T. Risthaus, A. Hansen, S. Grimme
Excited states using the simplified Tamm–Dancoff-Approach for range-separated hybrid density functionals: development and application
Phys. Chem. Chem. Phys. 16 (2014), 14408-14419.

T. Risthaus, S. Grimme
Benchmarking of London Dispersion-Accounting Density Functional Theory Methods on Very Large Molecular Complexes
J. Chem. Theory Comput. 9 (3) (2013), 1580–1591.

W. Uhl, J. Tannert, M. Layh, A. Hepp, S. Grimme, T. Risthaus
Cooperative Ge—N Bond Activation in Hydrogallation Products of Alkynyl(diethylamino)germanes(Et₂N)_nGe(C≡C^tBu)_{4 n}
Organometallics 32 (22) (2013), 6770–6779.


Tobias Risthaus
eMail: Tobias Risthaus