Number 212 (Story #1), January 30, 1995 by Phillip F. Schewe and Ben Stein A NEW EXPERIMENTAL STUDY OF BUCKYBALL SUPERCONDUCTIVITY furnishes further evidence for the idea that interactions between electrons and phonons (vibrational modes of the crystal lattice) are responsible for superconductivity in fullerides. The fulleride compounds, crystals of carbon-60 molecules doped with alkali atoms such as potassium or rubidium, can become superconducting at temperatures as high as 30 K and above, higher than for any other materials except the cuprate superconductors. Scientists at the Institute for Solid State Research in Julich, Germany and at the Max Planck Institute in Stuttgart have examined the photoemission spectra of negatively charged C-60 molecules. They use laser light to detach single electrons from the buckyballs; in the process, the departing electrons sometimes lose energy by exciting phonons in the cagelike C-60 molecules. The existence of the phonons and their energies can be deduced from the observed spectrum of the electrons. The German scientists feel justified in relying on the more easily interpretable spectra of gaseous C-60 (rather than that of crystalline C-60) and in asserting that these spectra support the notion of an electron- phonon mechanism as an explanation for C-60 superconductivity, because previous experimental and theoretical research had shown that the intra-molecular phonons (those thought to be responsible for superconductivity) are only slightly different for the solid and gaseous phases. (O. Gunnarsson et al., upcoming article in Physical Review Letters.)