Complex compounds of zinc nitrate with thiourea, benzamide and benzoic acid were synthesized. The advantages of the mechanochemical method, the optimal conditions of synthesis are presented. By means of IR-spectroscopy and differential thermal analysis methods, ligands and the complex compound formed on their basis, the nature of the bond, central atomic circle, polyhedron, shifts in valence and deformation vibrations, thermal stability, nature of effects, thermolysis products, residual products were determined.