Аннотация:Nitrate complexes of rare earth elements demonstrate a variety of composition and structure, but their properties remain insufficiently studied. Using both known and new synthetic approaches, previously unknown nitrate complexes of lanthanides were obtained in our work. The crystal structure of the obtained compounds was established by X-ray diffraction analysis. In the course of the work, a systematic study of nitrate complexes of rare earth elements with various counterions was carried out. In this case, several families were synthesized, which made it possible to trace the crystallographic regularities in the series of lanthanides and to reveal the stability limits for compounds of the same type:1. (NO)3[Ln2(NO3)9], Ln = La – Gd; (NO)2[Ln(NO3)5], Ln = Tb – Lu2. (A,B)2[Ln(NO3)5], Ln = Dy, Ho, Er, Tm, Yb, A,B = PyH, N-NO2Py, NO23. (PhenH2)[Eu(NO3)5]In addition, new synthetic approaches were tested, which made it possible for the first time to obtain nitrate complexes of a previously unknown composition and structure: framework (BMIM)6[La4(NO3)18](C2H4Cl2) (Fig. 1a) (BMIM – butylmethylimidazolium cation), chain NO[Ho(NO3)4], layered (Н3O)2[La3(NO3)11(H2O)2](H2O)5 (Fig. 1b).Anhydrous nitrate complexes of lanthanides can exhibit the properties of Lewis acids and find applications in organic catalysis. The presence of series of compounds of the same type makes it possible to trace the change in such functional properties as luminescence and molecular magnetism, as well as to reveal patterns between the composition, nature of the metal, and the manifested properties.Acknowledgements – This work was supported by NUST “MISiS” grant No. K2-2020-039“VII Russian Day of Rare Earth”, February 14–16, 2022 Arbuzov IOPC FRC Kazan Scientific Center of RAS