FT pulsed-ESR/electron spin transient nutation of hyperbranched polycationic organic high-spin polymers

As a novel electron magnetic resonance technique for the characterization of organic molecule-based magnets, an electron spin transient nutation method based on Fourier-transformed pulsed ESR spectroscopy was applied to polycationic organic polymers. The polymers are triphenylamine-based in the hyperbranched three-dimensional network with the unpaired electrons at the nitrogen cation sites. The FIDdetected nutation spectrum from one of the polymers exhibited several nutation-frequency components corresponding to high-spin species containing S=3. The static magnetic susceptibility of the polymer supported the high-spin ground state in the system under study. The present results demonstrate the potentialities of the charged high-spin polymers as well as the methodological advantage of nutation spectroscopy in identifying the spin multiplets of the molecule-based magnets in the frequency domain.