LOW-TEMPERATURE PROPERTIES OF CE(RU(1-X)M(X))(2)GE-2, M=FE, AU

We have performed measurements of electrical resistivity, AC susceptib ility, magnetization, Mossbauer effect and NMR on the series of interm etallic compounds Ce(Ru(1-x)M(x))(2)Ge-2, M = Fe, Au for 0 less than o r equal to x less than or equal to 0.1. The parent compound CeRu2Ge2 o rders ferromagnetically below 7.5 K, with f-electrons showing only a s mall mass-enhancement at low temperatures. However, its crystal struct ure and Fermi surface are closely related to the heavy-electron superc onductor CeRu2Si2. Analysis of X-ray diffraction patterns confirmed th e structure to be of the ThCr2Si2-type, with no foreign phases detecte d. The results of our Mossbauer studies indicate that Fe goes into the Ru sites with no magnetic moment. NMR signals were observed in the Fe -doped samples with quadrupolar interaction that can be related to Ge- 73 nucleus (I = 9/2).