**Abstract**

The possibility of the formation of India perchlorate and mixed ligand complexes has been studied. It is assumed that during the extraction of indium in aqueous solutions of hydrochloric acid at various concentrations and constant ionic strength maintained by the addition of perchloric acid, indium is present in the organic phase in the form of ionic aggregates HClO4 · HInCl4. To study the hydration of Ions, the method of electrical conductivity was carried out in the "In(ClO4)3 - HClO4 - H2O" system. The structure of aqueous solutions of India perchlorates was determined by IR spectroscopy. The structures of trivalent perchlorate India have been established.

**Keywords:** perchlorate ion, indium, gallium, complexation, ionic state, NMR, IR, extraction, coordination number
