Experimental and Theoretical Evidence for U(C₆H₆) and Th(C₆H₆) Complexes

Abstract

The vibrational spectra of UBz and ThBz have been measured in solid argon. Complementary quantum chemical calculations have allowed the assignments of the vibrational spectra. According to the calculations, AcBz are stable molecules, as well as other species like BzAcBz and BzAc2Bz. Experimentally, there is no evidence for the sandwich compounds BzAcBz and BzAc2Bz due to the limitations in the reagent concentrations

On the Nature of Actinide– and Lanthanide–Metal Bonds in Heterobimetallic Compounds

“…Nevertheless, the lack of a s and p bond does not conflict with the previous calculations. [11,15] Although there are no bonding and antibonding pairs, the previous DFT calculations suggest that orbital interactions contribute about thirty percent to the total bonding energy. The covalent interactions were described as "s and p donations".…”

“…For example, Th 2 was detected both in the gas phase and in a rare gas matrix while U 2 has been detected in the gas phase but not yet isolated. [9][10][11][12][13] However, many challenges remain regarding the preparation of molecules containing actinide-actinide bonds, particularly in moving beyond the diatom towards the synthesis of complexes that can be characterized by single-crystal diffraction. In fact, complexes containing homodinuclear unsupported actinide-actinide or lanthanide-lanthanide bonds have not been observed to date, but heterobimetallic metal-metal complexes containing one f-element have been.…”

Ionization Energies for the Actinide Mono- and Dioxides Series, from Th to Cm: Theory versus Experiment

“…35 This approach has been successful in studying many actinide-containing systems. 13,[36][37][38][39][40][41][42][43][44] In the CASSCF treatment, the ideal active space of AnO 2 [An ) Th, Pa, U, Np, Pu, Am, and Cm] would be composed of 19 orbitals, 13 of which come from a linear combination of the 5f, 6d, and 7s orbitals of the actinide atom and the remaining 6 from the 2p orbitals of the oxygen atoms. This means that the smallest active space, the one for ThO 2 , would contain at least 12 electrons, that is, 4 valence electrons from the Th and 8 valence electrons from the oxygen 2p orbitals.…”

The chemiionization reactions Ce + O and Ce + O2: Assignment of the observed chemielectron bands

“…Spin‐orbit coupling effects were computed using the complete active space state interaction (CASSI) method 10, 11, in which an effective one‐electron spin‐orbit Hamiltonian, based on the atomic mean field approximation of the two‐electron part, was employed. This approach has been shown to work successfully in a number of earlier applications 12–23. All calculations were performed using the MOLCAS 7.0 program package 24.…”