Recent Progress in Stable High-Spin Molecules Based on Nitroxide Radicals

Abstract

Organic-based open-shell π-electronic molecules are promising components for unique electronic devices because of the diversity in their design. Of these compounds, high-spin π-electronic molecules are attractive building blocks of molecule-based magnets and spintronic devices. However, there are only a few reports of high-spin π-electronic molecules with large intramolecular exchange interactions (Jintra/kB > + 300 K) and with isolable stability, although general guides of molecular designs to obtain high-spin π-electronic molecules have already been established. In this chapter, recent studies from our research group on high-spin π-electronic molecules are reported. First, stable trimethylenemethane analogues composed of nitroxide and nitronyl nitroxide or imino nitroxide moieties and their metal complexes are outlined. This is followed by the description of (nitronyl nitroxide)-substituted electron donor radical cations as new components for molecule-based magnets. Finally, a trinitroxide-substituted trioxytriphenylamine is discussed, which constitutes a novel spin-state conversion system.