BCS THEORY AND ISOTOPE EFFECT OF QUASI-ZERO-DIMENSIONAL SUPERCONDUCTORS NEAR THE MOTT TRANSITION

We calculate the B.C.S superconducting critical temperature of weakly coupled molecular levels as a function of the bandwidth B when the Deb ye energy omega(D) has the same order of magnitude is B, a case corres ponding to the Fullerenes, where B approximately 0.3 eV. For such a na rrow band, electron correlations should induce a pseudogap in the dens ity of states, leading to unusual behaviour of various quantities such as the isotope effect. These singular properties might disappear unde r strong enough pressure.