A very high-resistivity value ( p 4 ~-4300 p*ncm>, associated to a strong negative temperature dependence (a = l/p 1 &/AT --K-'), is measured in pure icosahedral A163C~25Fe12 phases (a single grain and polyq&erystalline samples). Moreover the resistivity of the defective as-quenched ~A&$2u25Felz samples is much smaller ( p 4 ~ -1300 yQcm) and increases sharply (up to -4300pQcm) after annealing treatment. We show also that the temperature and magnetic-field dependences of the resistivity and the Hall effect can be analysed through electron-electron interactions and localization theories.

An anomalous Hall effect is measured in pure decagonal A18OMn20 and A178Mn». We show that the Hall resistivity pH is linear with the magnetization M measured for the same fields and temperatures: pH(H T) =ROH +4wRsM (H T). The very dominant term RsM of p& reveals a strong spin-orbit scattering, which is observed in Al-Mn quasicrystals. Rs is found to be temperature independent in the range 6.5 -110 K. From our susceptibility, specific-heat, and magnetoresistance data, we deduce that M results from a very low fraction of magnetic moments, which increase drastically with the nominal Mn concentration and that are correlated by Ruderman-Kittel-Kasuya-Yosida interactions. In this respect, the Al-Mn decagonal phase behaves very similarly to previously measured Al-Mn icosahedral and amorphous phases.

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