Anisotropic magnetic behavior of PrAg 2Ge 2—a crystal field study

Abstract

A crystal field (CF) analysis of the experimental, single crystal magnetic susceptibility data (300–1.8 K) along and perpendicular to the [0 0 1] axis, of the Ag based rare earth intermetallic compound PrAg 2Ge 2, has been carried out for the first time, thus yielding first reliable set of CF parameters for the system. The susceptibility feature at 12 K is possibly due to CF effects rather than the magnetic order as proposed earlier. This removes the issue of the transition temperature being too large to scale properly with the de Gennes factor. We have used the set of CF parameters to find the Stark energies of the ground state and the excited states together with their corresponding eigenvectors, and the thermal variation of the magnetic specific heat. Possible explanation of the absence of magnetic ordering of the Pr sublattice and the nature of variation of the CF parameters with the substitution of transition-metal ion in PrAg 2Ge 2 is studied and discussed in relation to PrAu 2Ge 2. All computations have been carried out using the intermediate coupling scheme including the J-mixing.