TRANSPORT AND MAGNETIC-PROPERTIES OF RERUSN3 (RE = LA, CE, PR, ND, SM) - A HEAVY FERMION COMPOUND CERUSN3 AND A NEW VALENCE FLUCTUATING COMPOUND SMRUSN3

The electrical resistivity, thermoelectric power, Hall effect, magnetoresistivity, magnetic susceptibility and magnetization of intermetallic ternary compounds RERuSn3 (RE = La, Ce, PT, Nd and Sm), CeRuSnx (2.85 less-than-or-equal-to x less-than-equal-to 3.15), CeRu(Sn1-yIny)3 and NdRuSn2.91 have been measured. CeRuSn3 was reported to be a heavy fermion compound with an enormous coefficient of electronic specific heat gamma = 1.67 J K-2/mole at 0. 6 K. In order to gain a deeper insight into the heavy fermion state of CeRuSn3, non-stoichiometric compounds CeRuSn, (2.85 less-than-or-equal-to x less-than-or-equal-to 3.15) have also been investigated. The low temperature resistivity shows a maximum at x = 3.0 as a function of x. Sn deficient samples show three step phase transitions at 33 K. 4 K and 1.3 K. PrRuSn3 and NdRuSn3 do not show any magnetic ordering down to 1.8 K. SmRuSn3 is a new valence fluctuating compound with an antiferromagnetic ordering at 6 K.