Authors

Abstract

A series of actinyl(VI) nitrate salts of the form MAnO(2)(NO3)(3), where M = NH4+ K+, Rb+, Cs+, and Me4N+ and AnO(2)(2+) = U, Np, Pu, and AnO(2)(NO3)(2)(H2O)(2)& BULL;H2O, and the uranyl tetranitrates M2UO2(NO3)(4) have been synthesized from aqueous solution and their structures determined using single-crystal X-ray diffraction. Together, these complexes represent an isostructural series of actinide complexes among the salts crystallized with the same charge-compensating cation and have been studied using vibrational spectroscopy including Raman and Fourier-transform infrared. Periodic trends in both the structural properties of these complexes and their vibrational spectra are presented and discussed, in particular the invariant nature of the O equivalent to An equivalent to O asymmetric stretching frequencies observed across the actinyl series. Electronic structure calculations were performed at a variety of levels of theory to aid in the interpretation of the vibrational data and to correlate trends in the data with the underlying electronic properties of these molecules.