All-Electron Hybrid Density Functional Calculations on UFn and UCln (n = 1-6).

We calculate the bond dissociation energies of the series UFn and UCln (n = 1-6) using the all-electron third-order Douglas-Kroll-Hess approximation in combination with hybrid density functionals. The spin-orbit (SO) operator is included self-consistently using the nuclear-only SO and the screened-nuclear SO approximations. Results are in very good agreement with experimental values, with the exception of the smallest molecules of each series, UF and UCl. By shifting the one-electron orbital energies of UF6 and UCl6 to match the HOMO level with the ΔSCF calculated value of the first ionization energy, we are able to reproduce the main features of the photoelectron spectrum of these two molecules.