Relativistic DFT investigation for reaction energies and electronic/bonding properties of Schiff-base polypyrrolic uranyl(V) complexes: effects of group 14-functionalized uranyl exo-oxo group.

contextThe safe immobilization of radionuclides and the removal of nuclear waste contamination from environment require a thorough understanding of the structures, reaction behaviour and bonding properties of uranium complexes. The cation-cation interaction (CCI), which is also known as the direct actinyl-actinyl bonding interaction, is common only for An(V). A series of binuclear uranyl compounds of Schiff-base polypyrrolic macrocycle (H

methodsStructural optimizations of all compounds were performed in the gas phase using the Priroda code. A generalized gradient approximation (GGA) of the Perdew-Burke-Ernzerhoff (PBE) functional was used. All-electron correlation-consistent double-ς polarized quality basis sets were used in all calculations. Single point calculations have been performed by using the ADF 2012 code on the basis of optimized geometries from Priroda code. The scalar relativistic zero-order regular approximation (ZORA) method and Slater-type triple-zeta polarization (TZP) basis sets were employed. Solvation effects were considered with the Conductor-Like Screening Model (COSMO) and spin-orbit coupling (SOC) effects were explicitly included in the calculations. Single-point calculations were carried out using the Gaussian09 program. Stuttgart relativistic large-core effective core potentials (RLC-ECPs) and corresponding basis sets were applied for U, def2SVP for Sn and Pb, and 6-31G* for other atoms. Then, the quantum theory of atoms in molecules (QTAIM) data were computed with the Multiwfn 3.3.3 package.