**Acknowledgement**

We would like to express our sincere gratitude to Professor Svetlana B. Meshkova (A. V. Bogatsky Physic-Chemical Institute of National Academy of Sciences of Ukraine, Odessa) and Professor Vladimir N. Kokozay (Taras Shevchenko Kyiv University) for synthesized heteroligand rare-earth metal's and polyheteronuclear chelate compounds, respectively.
