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## II. EXPERIMENTAL DETAILS AND RESULTS 

Details of sample preparation were described in a previous paper [8]. Structural characterization con- firms the single phase composition of the sample in a tetragonal Mo 2 FeB 2 -type structure with a = 7 . 765 ˚ A and c = 3 . 902 ˚ A lattice parameters. The actual composition of the sample was determined to be Ce 2 . 005 Pd 1 . 988 Sn 0 . 997 after SEM/EDAX analysis. 

Specific heat was measured using the heat pulse technique in a semi-adiabatic He-3 calorimeter in the range between 0.5 and 20K, at zero and applied mag- netic field up to 4T. DC-magnetization measurements were carried out using a standard SQUID magnetome- ter operating between 2 and 300K, and as a function of field up to 5T. Electrical resistivity was measured between 0.5K and room temperature using a standard four probe technique with an LR700 bridge. 

As shown in Fig. 1, the magnetic field affects quite differently the specific heat C$_{m}$ ( T ) anomalies of both transitions. While the temperature of the lowest ( T$_{C}$ = 2 . 1 K) rapidly increases with field, the upper one ( T$_{M}$ = 4 . 8 K) reminds practically unaffected up to B = 0 . 2T. The well defined first order transition at T$_{C}$ ( B = 0) transforms into a broaden anomaly by the effect of applied field, which extends between 2 ≤ T ≤ 3 K for B = 0 . 1 T, see Fig. 1. Such a broad- ening can be explained by the poly-crystalline nature of the sample since the crystals are randomly oriented between the easy and hard directions of magnetiza- tion. This random orientation yields to a continuous distribution of transitions according to the respective projections of the crystals respect to the magnetic field. 

The fact that the jump of the specific heat remains unaffected and the temperature of the maximum value of C$_{m}$ (at T = T$_{M}$ ) does not decrease up to B = 0 . 2 T are further evidences that the upper transition cannot be considered as AF in a canonical sense. Neverthe- 

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less, the cusp of M ( T ) at that temperature reveals that some type of AF interactions play some role in the magnetic structure below T$_{M}$ . The lack of varia- tion of C$_{m}$ ( T ) for fields B ≤ 0 . 2 T indicates that the arguments used in Ref.[8] to recognize the formation of Ce-Ce pairs remains valid at low field. At higher field (i.e. B ≥ 0 . 5 T ) the maximum value of C$_{m}$ ( T$_{M}$ ) starts to decrease with a concomitant broadening of the anomaly, see Fig. 1. Such a behavior indicates that an induced ferromagnetic state sets in, which at B = 4T clearly tends to a Schottky-type anomaly. 

According to the C$_{m}$ ( T ) /T behavior depicted in Fig. 1, the temperature dependence of the magnetic entropy gain S$_{m}$ reduces its thermal increase as the external field increases. Independently of that reduc- tion, S$_{m}$ ( T ) reaches the full expected value of 2RLn2 at T ≈ 20 K even for B = 1 T . For highest measured field (c.f. B = 4 T) only 80% of the total entropy of the doublet GS is reached at that temperature (c.f. our upper limit of temperature). 

ρ ( T, B ) measurements, shown in Fig. 2a, indicate that magnetic correlations above T$_{M}$ are progressively quenched by magnetic field and the transition itself is smeared once the applied field induces the FM behav- ior. Concerning the lower transition, the ρ ( T ) hystere- 

