Structurally tuned magnetic properties of TbmRhnIn3m+2n (m=1,2; n=0,1) intermetallic antiferromagnets

We report the evolution of the magnetic properties of a new series of intermetallic compounds TbmRhnIn3m+2n(m=1,2;n=0,1) which are structurally related to a class of Ce-based heavy-fermion superconductors (HFS). Measurements of temperature-dependent magnetic susceptibility, specific heat and X-ray resonant magnetic scattering (XRMS) were performed on single crystalline samples of TbIn3, TbRhIn5 and Tb2RhIn8. The tetragonal materials TbRhIn5 and Tb2RhIn8 both order antiferromagnetically with higher ordering temperatures (TN=45.5 and 42.8K, respectively) than their cubic relative TbIn3(TN=32.7K). Their commensurate magnetic structure and the direction of Tb magnetic moments will be discussed in terms of crystalline electrical field (CEF) effects and Ruderman-Kittel-Kasuya-Yoshida (RKKY) interaction with effects of magnetic frustration being released by lower dimensionality. A more general picture about the role of CEF in determining the magnetic properties of other R-based members of these series is discussed