PRESSURE-DEPENDENCE OF THE ELECTRONIC DENSITY-OF-STATES AND T-C IN SUPERCONDUCTING RB3C60

The functional dependence of the superconducting transition temperatur e T-c on the electronic density of states N(E(f)) was determined for R b3C60 by measuring the magnetic susceptibility under hydrostatic press ure to similar to 1 GPa in a commercial SQUID magnetometer. Both T-c a nd N(E(f)) decrease under pressure at the rates -31%/GPa and -14.5%/GP a, respectively, but lie above the corresponding values for K3C60 at t he same lattice parameter. The present results are consistent with wea k-coupling BCS theory with characteristic energy E(char)/k(B) approxim ate to 320-810 K.