Cyano-Bridged d–f Ensembles of the Dysprosium Tetrapyridine Complexes with the Hexacyanoferrate Anion

The reactions of DyX3 · 6H2O (X = NCS, Cl) with 2,2':6',2''-terpyridine (Terpy) and K3Fe(CN)6 in aqueous-alcohol solutions afford cyano-bridged ensembles [Dy(Terpy)(H2O)3Fe(CN)6] · nH2O, [Dy2(Terpy)2(H2O)3(CO3)(NCS)Fe(CN)6] · 4H2O, and [Dy2(Terpy)2(H2O)4(CO3)(NCS)Fe(CN)6] · 11.4H2O. The compounds obtained are identified by the data of elemental analysis, IR spectroscopy, X-ray diffraction analysis, and X-ray structure analysis (CIF files CCDC nos. 1827138–1827140). The study of the magnetic properties of complex [Dy(Terpy)(H2O)3Fe(CN)6] · nH2O shows the low-spin state of Fe3+. The dynamic magnetic behavior of this complex exhibits a slow magnetic relaxation.