Georgia Zissimou

Georgia Zissimou

Affiliation: University of Cyprus

Research Interests: synthesis and oxidative stability of azaacenes including radicals, diradicals, zwitterions, quinoidal structures

Title: π-Systems in Motion: From Blatter Radicals to Azaacene Semiconductorsus

Abstract: High-spin organic radicals, n-type semiconductors, and non-fullerene acceptors (NFAs) are increasingly important in the development of advanced materials for electronics, spintronics, and optoelectronic applications. Among these, 1,2,4-benzotriazinyl (Blatter) radicals have emerged as robust, air- and moisture-stable species due to the delocalization of their unpaired electron. Their favorable stability and accessible synthesis have led to their incorporation in a wide range of functional systems, including OLEDs, photodetectors, pH sensors, liquid crystalline photoconductors, thin-film devices, quantum information platforms, and organic batteries.

Recent investigations have focused on higher-spin analogues of Blatter radicals, such as di- and tri-radicals and radicaloids. These systems offer enhanced magnetic interactions and stability through extended π-delocalization, positioning them as promising molecular building blocks for spintronic applications.

In parallel, nitrogen-containing polycyclic aromatic compounds—specifically azaacenes with five or more fused rings—are gaining traction for their tunable electronic and optical properties. Analogous to pentacene, these materials can act as organic semiconductors in transistors, light-emitting devices, memory storage, and photovoltaics. The substitution of carbon with nitrogen in the acene core can promote n-type behavior, although p-type variants have also been reported.

This presentation will highlight recent synthetic strategies and structure–property studies of Blatter-type radicals and azaacenes, emphasizing their potential as functional components in next-generation organic electronic and magnetic materials.