DYNAMIC NUCLEAR-POLARIZATION AND OVERHAUSER SHIFT ON C60 - RADICAL-ANION SALTS

Electronic and magnetic properties of C60- tetraphenylphosphonium radi cal anion salts have been studied with the help of magnetic resonance technique. By applying the Overhauser shift method the Dynamic Nuclear Polarization, nuclear spin-lattice relaxation times and Overhauser sh ift have been determined simultaneously. The very short nuclear spin-l attice relaxation times of C-13 and H-1 are caused may by localized el ectronic moments rather than by the relaxation via conduction electron s. The C-13 NMR signals from ''bucky-balls'' and phenyl groups of coun terions can be separated. The results point to the incomplete charge t ransfer from the counterion to C60 molecule resulting in a large Overh auser shift signal from protons and carbon nuclei of the counterion.