Crystal electric field in RAgSb2 (R = Ho, Er, Tm) intermetallic compounds

The magnetic scattering spectra of RAgSb2 (R = Ho, Er, Tm) intermetallic compounds are measured and their crystal electric field parameters are determined using inelastic neutron scattering. It is revealed that the ground state is a nonmagnetic singlet for the HoAgSb2 compound, a Kramers doublet with a strongly aniso-tropic g factor for the ErAgSb2 compound, and a quasi-doublet (random doublet) characterized by an extremely anisotropic g factor for the TmAgSb2 compound. The exchange interaction is estimated in the molecular field approximation. The magnetic properties of the RAgSb2 compounds are analyzed in terms of the energy level schemes and eigenfunctions determined in this study. The calculated anisotropic magnetic susceptibilities for all compounds are in good agreement with the experimental data obtained for single crystals.