Fine structure of the electronic absorption spectra of uranyl compounds

Abstract

The vibrational structure of electronic absorption spectra of uranyl compounds has been studied and the results applied to the influence of solvents, and of the hydrogen ions in aqueous solutions of the uranyl ion. These investigations illustrate the influence of solvents upon the energy of vibrational transitions, changes of band intensity and changes of general vibrational structure in the spectrum. It has been shown in the analysis that the vibronic spectra of the uranyl ion can be interpreted by superposition of vibrations on the electronic transitions. The magnitude of the totally symmetric vibration ν 1, the values of force constant, the distance U—O and the dissociation limit of a band progression 0″ - n′ have been determined. Hence the potential curve of one of the electronic excited states of uranyl has been calculated. The problem of the characteristic intensity distribution in the spectra of uranyl compounds has been discussed. In this connexion the influence of hydrolysis on the molecular structure of products of uranyl ion hydrolysis has been explained.