Infrared spectroscopic studies of some uranyl nitrate complexes

Abstract

The i.r. spectra of UO 2(NO 3) 2·6H 2O, UO 2(NO 3) 2(NH 3) 2, K 2UO 2(NO 3) 2F 2 and K 2UO 2(NO 3) 2(CN) 2 have been measured in the region from 4000 to 30 cm −1. The vibrational assignments of their skeletal vibrations have been made on the basis of a normal coordinate analysis in which a modified valence force field is assumed. Approximate force constants associated with the UO, UNO 3 and UL (LH 2O, NH 3, F, CN) bonds have been obtained for the respective complexes. The ligation effects on the UO bonds in the complexes have been investigated through the calculations of overlap integrals of 1π u -molecular orbitals in the uranyl bonding. It has been suggested that the UO stretching force constant, which is a good measure for the UO bond strength, is closely related to the overlap integrals of the 1π u -molecular orbitals.