Research

Functional Organic Molecules for Spintronics

 

Our group develops functional materials based on organic molecules that contain one or more unpaired electrons for applications in spin electronics or simply ‘spintronics’. The research in our group lies at the interface between organic synthesis, materials science, and supramolecular chemistry and revolves around spin-delocalized open-shell systems. Our biggest excitement is to design and make molecules, where new functionality arises from the presence of unpaired electrons. Our aim is to learn how to introduce and control multiple functionalities in a bulk material or a device made of these molecules, by manipulating spin interactions between the unpaired electrons.

 

One type of molecules that we investigate are π-conjugated hydrocarbons with a biradicaloid singlet ground state, which have recently emerged as a specific type of Kekulé polycyclic hydrocarbons. On account of their small HOMO–LUMO gaps and low-lying triplet excited states that can be populated thermally, organic biradicaloids hold potential as molecular building blocks for applications in spintronics. Last year, we reported the first helically twisted biradicaloid hydrocarbon, “C”-shaped cethrene, an isomer of a “Z”-shaped and planar biradicaloid zethrene. We showed that in cethrene, the singlet–triplet (S–T) energy gap is significantly decreased, compared to its isomer heptazethrene, on account of through-space interactions that arise within the frontier molecular orbitals because of the helical twist.

 
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