Solid (dibenzo-18-crown-6)KC60: significant enhanced air-stability and appearance of a strong 13C NMR signal of C60– below 200 K with an unexpected negative chemical shift
Abstract
Two novel properties, which arise primarily from intermolecular interactions between two aryl rings of the crown ether and neighbouring C60–, are found in solid (dibenzo-18-crown-6)KC60, viz. significantly enhanced air-stability and appearance of a strong 13C NMR signal of C60– below 200 K with an unexpectedly negative chemical shift.