Our main research objective is the design of transition-metal based structures that convert electric and chemical bond energy in an efficient manner. More specifically, we address the mechanistic details how multiple electrons (or holes) can be stored in a molecular coordination compound and how charge storage couples to moving multiple electrons to or from a substrate such as a H+ or H2. We pursue this objective by a mechanism-inspired strategy that relies on the principal triad: platform design – electron-precise metal structures – understanding structure-function-relationships.
A.B. is indepted to the Stipendien-Fonds der Chemischen Industrie, the Eliteprogram for Postdocs of the Baden-Württemberg Stiftung, and the Deutsche Forschungsgemeinschaft (DFG) for the financial support of research projects.
At present, we make use of the unique physical and chemical properties of metal-sulphur bonds of late transition metal thiolate complexes for the named purpose. Following our pincipal strategy, we designed a structurally and electronically flexible thiolate-arene-thiolate platform that stabilizes a series of electron-precise nickel-sulphur structures that perform hydrogen oxidation and formation, just depending on their redox-state. This unique [Ni2S2] system is ideal for studying the mechanistic aspects of two-electron storage and reactivity. The same platform allows us to explore the intruiging electronic and reactivity properties of radical-ligand structures of the group 10 metals that perform complementary reactivity: free radical chemistry.
The following three examples briefly highlight the strategy that we pursue to devise defined electronic structures for detailed studies of reactivity and physical properties.
Single-crystal X-ray diffraction, variable temperature magnetic spin resonance, vibrational and electronic absorption spectroscopy and electrochemistry are routine experimental techniques applied in studying electronic structure-property relationships. Expertise of collaborators on computational studies of electronic structure-property relationships of open-shell coordination compounds has complemented and expanded the scope of our experimental efforts.