The Wärnmark Group
The KW group during the annual group excursion, this time a hike from Knivsåsen to Skrylle. September 2022
Research - Main Fields
Currently, Iron Carbene Sensitizers are a big part of research in our group, where the electronic properties of iron complexes are studied and adjusted. Using strongly σ-donating N-heterocyclic carbene (NHC) ligands, the aim is to alter the energy of electronic states in iron complexes, making them potential candidates as photosensitizers in solar cells. Because of abundance and availability of iron, replacing the widely employed, scarce, ruthenium and iridium-based complexes is an exciting prospect. The challenge is to extend the lifetime of a short-lived triplet metal-to-ligand charge transfer (3MLCT) excited state by increasing the complex ligand field and destabilizing a low-lying metal-centered state (MC).
Picture: Lisa A. Fredin, Front Cover ChemSusChem, 9(7) 2016
Another project is within the field of Supramolecular Chemistry - the chemistry beyond the molecule. This means that we are using non-covalent interactions between molecules, mainly hydrogen bonds, to construct assemblies of molecules that should have new properties that are more than the sum of the individual molecules. Self-assembly is used in Nature to build up organs such as the brain from smaller components. In our group we use advanced organic chemistry to covalently build up the molecules (building blocks) we want to assemble by non-covalent interactions after designing the molecules with respect to hydrogen-bonding pattern and their spatial positions to form the desired aggregate. For this purpose we use molecular modeling and quantum mechanical calculations. Characterization of the so formed assembles in solution is challenging and a lot of effort is devoted to apply and to develop methods for their characterization, some involving advanced mathematics.
Picture: Dovilė Račkauskaitė, Front Cover JACS 33/2015