Mononuclear Lanthanide Complexes in Triangular Dodecahedron Geometry: Manifestation of Single Ion Magnet Behavior for DyIII Analogue

In this work, a tridentate N,N,O ligand [(E)-4-nitro-2-((pyridine-2-ylmethylene)­amino)­phenol] (LNO2H) is employed for the synthesis of neutral structurally similar complexes [DyIII(LNO2)2(Cl)­(H2O)]•H2O (1) and [ErIII(LNO2)2(Cl)­(CH3OH)]•3CH3OH (2). Both complexes are characterized by single-crystal X-ray diffraction studies. LnIII ion in complexes 1 and 2 is eight coordinated and possesses triangular dodecahedron geometry as confirmed by the SHAPE analysis. The Hirshfeld surface calculation emphasizes the importance of hydrogen bond interaction that controls the overall crystal packing. The magnetic studies reveal that complex 1 shows single ion magnet (SIM) behavior with an effective energy barrier of 34.16 K and pre-exponential parameter 6.51 × 10–6 s. The CASSCF based ab initio calculations were performed on complexes 1 and 2 to extract SH parameters and the plausible magnetic relaxation dynamics.