Synthesis, Crystal Structure and Luminescent Properties of [{Eu(1–x)Nd(1+x)(H2O)5(NO3)}2CB[6]] (NO3)4·HNO3·6H2O (x = 0.5, –0.5)

Supramolecular adducts of lanthanide complexes with cucurbituril, [{Eu_(1–x)Nd_(1+x)(H₂O)₅(NO₃)}₂ CB[6]](NO₃)₄·HNO₃·6H₂O (x = 0.5, –0.5), are prepared by heating a mixture of dissolved lanthanide nitrates and cucurbit[6]uril. According to the single-crystal XRD data for 1 and 2, the metal is connected to the macrocycle through the bidentate coordination of oxygen atoms of cucurbit[6]uril portals to the lanthanide(III) cations, thus leading to the formation of a molecular complex. In the crystal, the [{Ln(H₂O)₅(NO₃)}₂(CB[6])]⁴⁺ cations are interconnected by a system of hydrogen bonds. The compounds are shown to be isostructural and are characterized by a number of physicochemical methods: IR spectroscopy, powder XRD, and elemental analysis. Their luminescence spectra are recorded.