Superconductivity of potassium and rubidium heterofullerides modified with low-melting alloys

The paper provides experimental data on the synthesis and study of the superconducting properties of potassium and rubidium heterofullerides modified by Wood’s alloy — Sn, Pb, Bi, Cd (hereinafter W) with a melting temperature Tm = 61.5 °C or Y alloy — Bi, Sn, Pb, In, Cd, Tl with Tm = 41.5 °C. The synthesis of heterofullerides was carried out by the interaction of fullerides of the composition K2C60 and Rb2C60, which do not have superconducting properties, with one of the alloys W or Y in an organic solvent — toluene at 100–110 °C. The samples obtained in this case showed superconducting properties with Tc = 8 K for K2YC60 and Rb2WC60 and 16 K for K2WC60.