Mass and Lifetime Enhancement due to Disorder onAgcPd1−cAlloys

Residual resistivities of ${\mathrm{Ag}}_c{\mathrm{Pd}}_{1-c}$ alloys for $0.2<~c<~0.8$ were calculated from first principles using the Korringa-Kohn-Rostoker coherent-potential approximation and yielded quantitiative agreement with experiment with no adjustable parameters. Some aspects of Mott's $\mathrm{sd}$ model are confirmed, but the $s$ sheet velocities and lifetimes vary in a surprising manner with concentration because of the energy dependence of the disorder self-energy at the top of the $d$-band complex. These variations are analogous to electron-phonon mass and lifetime renormalization.