New preparation of superconducting alkali-metal fullerides utilizing monomethylamine as solvent

Abstract

Monomethylamine is employed as a solvent for the preparation of alkali-metal (K, Rb, Cs and mixtures) doped [60]fullerene (C₆₀). Not only is the initial solution homogeneous, but also the extended temperature range of this solvent, as compared to ammonia, provides favourable conditions for the preparation of single phase, well defined materials with high superconducting volume fractions. The materials were characterized by dc magnetization and X-ray diffraction measurements.