Structure of uranyl complexes with o.o'-dihydroxyazo compounds

1. Reversible transient changes in the complexes of uranyl with the disodium salt of 1-(2-hydroxy-3,5-dinitrophenylazo)-2-hydroxynaphthalene-3, 6-disulfonic acid, which are explained by cis-trans isomerization, were detected by the pulse spectroscopy method. 2. A study of the IR absorption spectra of the ligand and the complex confirmed the postulation that the uranyl ion reacts with only one OH group of the coordinated ligand, which functions as a bidentate ligand in this complex. 3. A structure was proposed for the investigated complex on the basis of the IR spectral and elemental analysis data.