Number 67 (Story #1), February 12, 1992 by Phillip F. Schewe and Ben Stein BUCKYBALL SUPERCONDUCTIVITY IS MEDIATED BY PHONONS . This is the interpretation scientists at AT&T Bell Labs give to their studies of superconducting compounds of rubidium and carbon-60. They observed that when 13C atoms were substituted for 12C atoms in buckyball molecules, the critical temperature of the Rb3C60 sample decreased by an amount one would expect from BCS theory, which describes superconductivity in terms of electron pairs mediated by phonons (lattice vibrations). An "isotope shift" of this type has been observed in many low-temperature metal superconductors. (A.P. Ramirez et al., 17 Feb. 1992 issue of Physical Review Letters; contact Arthur P. Ramirez, 908-582-2494.)