Welcome to the Knecht Group webpage. We have recently been relocating to the Superheavy Ion Research Center (GSI) in Darmstadt/Germany. 🙂 Find information about our research interests and our latest software developments.

Our research is centred around the density matrix renormalization group (DMRG) approach, which is on the edge of becoming a well-established electronic structure method in chemistry to tackle the exponential scaling problem of solving a full-configuration-interaction type problem. We are particularly interested in developing DMRG-based ab initio wave function methods – possibly combined with density functional theory (DFT) – that allow for the prediction of electronic and magnetic properties such as X-ray, UV-Vis, EPR and NMR spectra of closed and open-shell molecules covering any element of the periodic table of elements.

Other research interests include the (range-separated) ensemble DFT method for the calculation of ground- and excited states (properties) formulated in a time-independent framework as opposed to the widely used time-dependent (TD)-DFT approach, the implementation and development of relativistic multiconfigurational methods, the description of excited-state (reaction) dynamics and the implementation of embedding approaches for (DMRG-based) ab initio wave function methods, aiming towards the study of chemical reactions including solvent and/or protein matrix effects.

Further information about our research and publications can also be found at ResearcherID and ResearchGate.


  • 19-07-2020: Fruitful outcome of our collaboration with the experimental group of F. Merkt (ETH Zürich)! Stay tuned for reading about our work on a “Complete characterization of the 3p Rydberg complex of a molecular ion: MgAr+. I. Observation of the Mg(3pσ)Ar+ B+ state and determination of its structure and dynamics.” which has just been accepted for publication in J. Chem. Phys..
  • 08-06-2020: New date for my Nernst-Haber-Bodenstein award 2020
    price ceremony by the German Physical Chemistry Society (Deutsche Bunsengesellschaft): November 10th 2020 live from the University of Giessen (Germany) starting at 2.30 pm (CEST). More news and video link will follow here. Stay tuned.
  • 02-06-2020: Started my new position as Scientist in the Superheavy Elements Chemistry group at GSI Darmstadt today.
  • 29-05-2020: New paper submitted: Complete characterization of the 3p Rydberg complex of a molecular ion: MgAr+. I. Observation of the Mg(3pσ)Ar+ B+ state and determination of its structure and dynamics.
    A great collaboration with my experimental colleagues from the Merkt lab.
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                 with two kids at home ...
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  • pre-/mdi-CORONA works: check out my software collaboration papers on [Open]Molcas and DIRAC.
  • 01-11-2019: Check out my “Trendbericht Theoretische Chemie: Relativistische Quantenchemie” summarising the latest developments in relativistic (multi-configuration) electron correlation approaches.
  • 25-09-2019: Looking forward to write an “invited Perspective review” article on relativistic (multi-configuration) electron correlation approaches and their application to heavy-element chemistry for PCCP.
  • 07-05-2019: New paper submitted: Analytical gradients and nonadiabatic couplings for the state-average density matrix renormalization group self-consistent field method. A giant leap forward towards ab initio dynamics with DMRG-SCF wave functions. 🙂
  • 28-03-2019: Exciting news on my (long-term) project regarding state-averaged DMRG-SCF in a relativistic framework. The implementation is done and I am writing the paper right now. So look forward to read more soon. As a byproduct, the code also works with an external magnetic field applied. See below one of the bonding “πu” orbitals in N2+ when applying an external magnetic field of B = 20 000 Tesla…

  • 22-01-2019: Back from Kobe/Japan with good inspirations for new projects to work on in 2019. We even had a chance to see the year 2012-fastest supercomputer (“K computer”) in the TOP 500 list.
The K supercomputer at RIKEN/KOBE in the back

Our work on U2 is featured on the cover of January’s 2019 Nature Chemistry issue

(cover design by Tulsi Voralia)