METALLURGICAL, STRUCTURAL AND MAGNETIC-PROPERTIES OF CE(PD1-RRHR)(2)SI-2

We report on investigations of the metallurgic, crystallographic and m agnetic properties of the Ce(Pd1-rRhr)(2)Si-2 system. While the as-cas t samples show a miscibility gap for 0.3<r<0.7, complete miscibility w ith a monotonous evolution of the lattice parameters is found in sampl es annealed at 1200 degrees C. Although both pure compounds order anti ferromagnetically at 10 K (r=0) and 36 K (r=1) respectively, our magne tic susceptibility (chi) results indicate a magnetically non-ordered s tate at intermediate concentrations. The ordering temperature decrease s smoothly and continuously on the Pd-rich side, vanishing between r=0 .2 and r=0.3. On the Rh-rich side, this decrease is faster and at r=0. 8 the long-range magnetic order is replaced by enhanced magnetic fluct uations as evidenced by a broad maximum in chi(T) around 25 K. The ori entation-dependent chi of the strongly textured samples indicates an e volution towards an easy-axis system with increasing Rh content. The r esults are discussed and compared to the related systems Ce(Pd1-xTx)(2 )Si-2 (T=Ru and Cu). (C) 1998 Elsevier Science S.A.