Band-structure effects on the electronic properties of icosahedral alloys

Distinct deviations from smooth trends of the Hall coefficient, thermopower, and electronic specific heat with the composition in icosahedral AlCuMg and GaZnMg alloys are observed. These arise in regions where the free-electron Fermi wave vector is predicted to lie near Bragg planes determined from strong x-ray-diffraction maxima. Our results provide the first experimental evidence for anomalies in the electronic density of states near the Fermi level in these alloys, which may be important in the stabilization of this class of icosahedral phases via Hume-Rothery considerations.