Magnetic properties of 9,9-disubstituted 9,10-dihydroacridine-10-yloxyls

Ferromagnetic intermolecular interactions were observed for 9-R-9-(pentadeuteriophenyl)-9,10-dihydroacridine-10-yloxyls (R=n-C12H25, n-C13H27). Superexchange-like interaction across the 9-phenyl ring is proposed, as illustrated by acridinoxyl ∥ phenyl ⊥ acridinoxyl, where the symbols ∥ and ⊥ denote the presence and absence of orbital overlaps, respectively.