Investigation of single ion crystal field anisotropy in heavy fermion compounds CeIr3B2 and PrIr3B2

The ferromagnetic transition Tc=41 K of CeIr3B2 is the second highest Tc recorded after CeRh3B2 in among Ce-based compounds makes it an interesting candidate to investigate using inelastic neutron scattering (INS). The isostructural PrIr3B2 compound also exhibits magnetic ordering at TN=10 K in addition to expected structural transition at 280 K. The susceptibility of these compounds exhibits considerable strong anisotropy. Interestingly the susceptibility of CeIr3B2 reveals a crossover behavior at high temperature (250 K) from easy ab-plane to hard c-axis. Therefore, the detailed study of crystal field excitations (CEF) using INS on MERLIN is proposed to explore the role of CEF anisotropy on the magnetic ground state. This study will be helpful to explain the role of CEF anisotropy in the observed behavior of the magnetic susceptibility and will shed light on the crossover behavior.