The mechanism of Fe induced bond stability of uranyl(v)

Abstract

The stabilization of uranyl(V) (UO2+) by Fe(II) in natural systems remains an open question in uranium chemistry. Stabilization of UVO2+ by Fe(II) against disproportionation was also demonstrated in molecular complexes....

Np(V) Retention at the Illite du Puy Surface

“…This suggests stronger covalent interaction between the Np­(V) sorbed and O eq of the clay binding site compared to Np­(V) aq . Similar empirical observations have been made for U­(V) complexes (compounds 2 and 7) . Lower UO ax bond covalency was found for 2, but the electronic density on U remained similar as a result of differences in the U-equatorial ligand interaction.…”

“…Similar empirical observations have been made for U(V) complexes (compounds 2 and 7). 59 Lower U�O ax bond covalency was found for 2, but the electronic density on U remained similar as a result of differences in the U-equatorial ligand interaction. Additionally, the intensity of the shoulder B′ is lower in comparison to shoulder B, indicating that a fraction of Np(IV) might also be present.…”

Electronic Structure of Actinyls: Orbital Properties

“…With the foundation laid for the orbital character, we will in a future paper apply this analysis of the orbital covalency as a basis to determine the orbitals to be used in a study of the many-body wave functions of the initial and, especially the M 4 and M 5 excited states. This later work will allow us to obtain theoretical predictions to compare with observed X-ray absorption spectroscopy, XAS, especially for the near-edge XAS, X-ray absorption near edge spectra (XANES). , However orbital analysis, especially the covalent character of the orbitals, is of value in itself to understand chemical bonds and chemical bonding. This value of orbitals was recognized by Mulliken and he developed the method of population analysis as a means to understand orbital character. − As well as characterizing the atomistic composition of orbitals, population analysis makes it possible to distinguish bonding from antibonding orbital character.…”

“…2,3 Understanding of spectral data from cuttingedge X-ray spectroscopic tools using advanced theory is essential for properly interpreting bonding properties including stability and reactivity relations. 4 However, precise computations remain challenging due to the large number of electrons and their relativistic nature in large actinide systems. One specific open question is, can we infer bond covalency for the actinyl molecules by advanced X-ray spectroscopy and correlate the results to advanced theory?…”

“…This later work will allow us to obtain theoretical predictions to compare with observed X-ray absorption spectroscopy, XAS, especially for the near-edge XAS, X-ray absorption near edge spectra (XANES). 4,12 However orbital analysis, especially the covalent character of the orbitals, is of value in itself to understand chemical bonds and chemical bonding. This value of orbitals was recognized by Mulliken and he developed the method of population analysis as a means to understand orbital character.…”