THE INFLUENCE OF Y-DILUTION ON THE CRYSTALLINE ELECTRIC-FIELD PART OFTHE POINT-CONTACT SPECTRA OF VAN VLECK PARAMAGNET PRNI5

We report on the study of the influence of Y dilution on the crystalli ne electric field (CEF) in the Van Vleck paramagnet PrNi5 using point- contact (PC) spectroscopy. PC spectra of Pr1-xYxNi5 compounds (x = 0,0 .02, 0.05, 0.1 and 0.21 in the ballistic regime have been measured. A shift of the main CEI: peak (Gamma --> Gamma(5)(2)) situated at about 4.2 meV for x = 0 to 5.1 meV for x = 0.2 is observed. This shift is in agreement with that obtained from susceptibility measurements in this system. The asymmetry in the dV/dI dependences of all heterocontacts could be explained by the model taking into account the difference in effective masses of conduction electrons.