Antiferromagnetic transition in CePd<SUB>2</SUB>B<SUB>2</SUB>C and possible heavy-fermion behaviour in CePt<SUB>2</SUB>B<SUB>2</SUB>C

Our measurements of the magnetic susceptibility, resistivity and specific heat of CePd2B2C, a quaternary borocarbide, show clearly that Ce is in a stable trivalent state in this compound and orders antiferromagnetically at TN ~4.5 K. In contrast, our preliminary investigations of CePt2B2C suggest that replacement of Pd by Pt led to the formation of a heavy-fermion state without magnetic ordering down to 2 K