Magnetic properties of McTa2S2C (M = Fe, Co, Ni, Cu) have been studied using SQUID DC and AC magnetic susceptibility. In these systems magnetic M 2+ ions are intercalated into van der Waals gaps between adjacent S layers of host superconductor Ta2S2C. Fe0.33Ta2S2C is a quasi 2D XY -like antiferromagnet on the triangular lattice. It undergoes an antiferromagnetic phase transition at TN (= 117 K). The irreversible effect of magnetization occurs below TN , reflecting the frustrated nature of the system. The AF phase coexists with two superconducting phases with the transition temperatures Tcu = 8.8 K and T cl = 4.6 K. Co0.33Ta2S2C is a quasi 2D Isinglike antiferromagnet on the triangular lattice. The antiferromagnetic phase below TN = 18.6 K coexists with a superconducting phase below Tcu = 9.1 K. Both Ni0.25Ta2S2C and Cu0.60Ta2S2C are superconductors with Tcu (= 8.7 K for Ni and 6.4 K for Cu) and T cl (= 4.6 K common to McTa2S2C). Very small effective magnetic moments suggest that Ni 2+ and Cu 2+ spins are partially delocalized.

In this work, magnetization studies on quasi bi-dimensional nanoparticles of Pd encapsulated in a graphite host as a function of magnetic field and temperature are presented. We found that an important magnetic signal can be attributed to the Pd nanoparticles. The obtained magnetic behaviour is interpreted in view of theoretical studies which predict ferromagnetism in slabs of Pd with some monolayers of thickness.

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