Localization of Co-3d electrons in Y(Co1-xAlx)(2) paramagnetic alloys withitinerant spin fluctuations

Thermoelectric power (S) and electrical resistivity (rho) of Y(Co1-xAlx)(2) alloys with x in the range of 0-0.15 have been measured at temperatures fr om 2 to 300 K, in the longitudinal magnetic field of 0-15 T. The present re sults show that there is a rapid variation of the transport properties and a peculiarity in the dependency of lattice parameter on x at x approximate to 0.03; however, no change of the lattice symmetry has been detected. Alth ough the precise mechanism of the anomaly at x approximate to 0.03 has not been understood, the results suggest that it is related to a change in the localization of the Co-3d electrons caused by the increasing Go-Co separati on and by the disorder within the Co-sublattice in the Y(Co1-xAlx)(2) alloy s. (C) 2000 Elsevier Science B.V. All rights reserved.