University of HeidelbergInterdisciplinary Center for Scientific Computing

Theoretical/Quantum Chemistry

Group of PD Dr. Markus Pernpointner

Institute of Physical Chemistry
Theoretical Chemistry Group Heidelberg

Open Positions

Master thesis on the following subject:

Investigation of the relativistic Renner-Teller effect in the X-CN (X=Cl, Br, I) photoelectron spectra by application of accurate electronic structure and quantum dynamical methods.

An initial quantum chemical study on the relativistic Renner-Teller effect in the Br-CN cation was already undertaken by application of a quadratic vibronic coupling model (QVCM) in combination with accurate four-component Fock space coupled cluster methods (J. Phys. B, 46, 125101, 2013).
We could hereby obtain accurate linear and quadratic coupling parameters for the interaction of the two spin-orbit-coupled surfaces of the Br-CN cation. Our approach was compared to alternative routes based on the direct evaluation of matrix elements in order to obtain the required parameters. Usage of the QVCM hereby was resticted to the coupling mode (bending) and based on fully relaxed four-component FSCC calculations. In the next step we want to go beyond this initial investigation and the following steps will be covered by the master project:

* generation of the coupling 3D hypersurfaces for the BrCN cation including all internal coordinates.
* Performing a high-quality numerical fit of the surfaces with Morse-type functions. Linear combinations of polynomials have not shown the required accuracy.
* Doing quantum dynamics on the generated surfaces fully covering relativity and coupling of states and modes. Derivation of the spectrum.

Last updated 15.04.2016. © Copyright University Heidelberg. Publishing Information.