Magnetic resonance and magnetic susceptibility study of vanadium oxide—decylamine nanotubes

We report on magnetic susceptibility, ⁵¹V NMR and EPR study of multiwall vanadium oxide—decylamine nanotubes. Our measurements reveal the presence of a diamagnetic V⁵⁺ and two paramagnetic V⁴⁺ ions, respectively. NMR spectra and magnetic susceptibility data estimate the V⁴⁺ ions as ∼31%–35% of the entire vanadium ions content. EPR evidences that the paramagnetic V⁴⁺ subsystem consists of ∼10% of individual ions (hyperfine structured polycrystalline pattern) and ∼90% of exchange coupled entities (Lorentzian line). (paper)