Magnetization and specific heat of CePd1-xNixAl

CePdAl crystallizes in the hexagonal ZrNiAl-type structure (space group $P\overline {6} 2m$), where the magnetic Ce3+ ions form a network of equilateral triangles in the ab plane similar to the kagome lattice. It is a well known antiferromagnetic heavy-fermion system with Neel temperature TN=2.7K. Magnetization and specific-heat measurements performed on CePd1xNixAl polycrystals show that the antiferromagnetic order in the system is suppressed by Ni substitution. TN is reduced to zero temperature at a Ni concentration x=0.144. At high temperatures the magnetization data follow a CurieWeiss law. The Weiss temperature $\Theta $ is negative with $\left| {\Theta } \right|$ increasing with x possibly due to the increasing Kondo effect. Indeed, the Kondo temperature increases with x as documented by an analysis of the specific heat and magnetic entropy of CePd1xNixAl for the samples with x=0, 0.062, 0.097, and 0.144. (C) 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim