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Double- and triple-decker lanthanide phthalocyaninates reveal single-molecular magnetic (SMM) behaviour, which is characterized by exceptionally high energy barriers and blocking temperatures [1]. Further improvement of SMM properties of sandwich lanthanide complexes can be achieved by the increase of the number of decks, which provides multinuclear complexes with f-f coupling between proximal Ln3+ ions. Among the ways to form extended complexes based on sandwich phthalocyaninates, cation-induced assembling of crown-substituted complexes attracts special attention. In the present work we have firstly shown that this method affords formation of supramolecular assemblies, whose architecture is the same both in solution and in solid state. This investigation was performed on the example of the previously synthesized model complex (1), which contains one terminal crown-substituted deck capable of cation-induced dimerization in the presence of potassium ions [2]. The interaction of (1) with KOAc in solution was studied using UV-Vis and NMRtitrations together with NMR DOSY, the results were consistent with the formation of the dimer. Finally, the structure of the dimer was firstly proved by single crystal XRD of solvates (1)2*(KBPh4)4·4(CH3CN)·7(CHCl3), which were obtained by slow diffusion of KBPh4 in CH3CN into the solution of (1) in CHCl3 at 25 °C. Comparison of the hydrodynamic radius deduced from NMR DOSY and molecular size from XRD analysis revealed that these data are in good agreement with each other. The structural characteristics of the dimer suggest the possibility of the magneticdipolar f-f interaction between the ions at M1 and M2 cites, as well as additional weaker coupling between ions at M2 and M2' cites, which can be observed in the case of isostructural complexes with Tb(III) and Dy(III).
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