Magnetic behaviour of a spin-canted asymmetric lanthanide quinolate trimer

Abstract

An asymmetrical dysprosium trimer with a molecular formula of [Dy₃(hq)₇(hqH)(NO₃)₂(H₂O)] was obtained through a reflux reaction employing as starting material Dy(NO₃)₃·nH₂O and 8-quinolinoline as ligand. Magnetic susceptibility investigations show the system to be an SMM, which was corroborated by sub-Kelvin μSQUID studies. Upon cooling, the magnetic susceptibility also exhibits a decrease in the χ_MT product, which was confirmed to be due to intramolecular antiferromagnetic interactions. μSQUID measurements, moreover, reveal a marked magnetic behaviour in the angular dependence of the hysteresis loops. The latter is a direct consequence of the non-colinear spin arrangement of the anisotropy axes of each Dy(III) ion in [Dy₃(hq)₇(hqH)(NO₃)₂(H₂O)] and the interaction between the ions, as also evidenced by CASSCF calculations. Our results evidence the effect of spin canting along with the intramolecular interactions, which can induce non-trivial magnetic behaviour in SMMs.