2025/07/21 by Arneth, J., Pachl, C., Greif, G. +4
#FOS: Physical sciences #Strongly Correlated Electrons (cond-mat.str-el)
paper · doi:10.48550/arxiv.2507.15547
We report the synthesis, crystal structure and magnetic properties of the triply-capped, slightly distorted trigonal-prismatic complex [Er(PPTMP)2(H2O)][OTf]3 (PPTMP = (4-(6-(1,10-phenanthrolin-2-yl)pyridin-2-yl)-1H-1,2,3-triazol-1-yl)methyl pivalate) (1). Complex 1 is shown to exhibit field-induced slow relaxation of the magnetisation at B = 0.1 T via two distinct relaxation paths. Using tunable high-frequency/high-field electron paramagnetic resonance spectroscopy, we experimentally determine the effective g-factors and zero field splittings of the two energetically lowest Kramers doublets (KD). Our data reveal that the triply-capped, slightly distorted trigonal-prismatic ligand field favours an m ≃ ± 9/2 magnetic ground state, while the main contribution to the first excited KD at Δ1 → 2 = 780(5) GHz is suggested to be m ≃ ± 5/2. The ground state g-tensor has generally axial form but hosts significant transversal components, which we conclude to be the source of SMM-silent behaviour in zero field. Our findings are backed up by ab-initio spin-orbit configuration interaction calculations showing excellent agreement with the experimental data.