Research Projects

The hypothesis that the unpaired spin of organic radicals/radical ions might serve as the elemental metal-like charge carrier and magnetic properties, motivated the preparation of such molecules. A few radicals displaying good conductivity have been prepared after Haddon’s conclusion that lowering the potential energy barrier to charge transfer (U) is required to the point of the low kinetic energy of the unpaired electrons. However, radical ions (anions/cations) have been unexplored for conductivity applications due to the unavailability of stable radical ions. Like organic open-shell materials, stable closed-shell electron-deficient materials exhibit extraordinary properties as n-type semiconductors for the preparation of next-generation optoelectronic devices such as OLEDs, OFETs, and OPVs. Again, low-lying LUMO made its isolation difficult, since it would react with moisture, solvents, and silica! Stable organic radical anions and their neutral electron-deficient precursors are challenging targets, but they promise multifunctional properties that combine magnetic, optical, conductivity, and transport properties. Moreover, the LUMO energy of a π-conjugated organic scaffold can be greatly lowered by introducing electron-withdrawing groups over the periphery of the skeleton which ultimately increases the electron uptake probability and helps in radical anion stabilization is well known. organic materials having low-lying LUMO levels provide extra options because of the design and synthetic tailorability, that can lead to tuneable optoelectronic properties. Unlike inorganic semiconducting materials, organic compounds have sufficient solubility. Therefore, it is easy to fabricate low-cost devices. Among many synthetic scaffolds pyrene has attracted huge attention because of its unique photophysical properties and easy functionalization. However, pyrene-based electron-deficient materials and radical ions are rare, and no report exists on the K-region substituted stable radical anions. As the search for stable open-shell materials with metal-like charge carriers and magnetic properties is ongoing, and extended π-conjugated organic systems seem to be excellent candidates, this suggests that a new molecular design of the electron-deficient system might provide stable radical anions with exceptional optoelectronic properties. The present proposal is to explore the synthesis of new ambient stable radical anions/ dianions/ diradical dianions and their electron-deficient precursor materials for organic electronics. We proposed the design of new pyrene-based electron acceptors incorporating pyrazine, benzothiazole (BT), benzothiazole quinone (BTQ), Indanone, benzothiophene (BTP), cyano, keto, malononitrile, sulfoxide, and sulfone as electron-withdrawing groups. We expect these electron-deficient compounds and their stable radial anions will provide excellent materials for electronic applications.