Actinide inverse trans influence versus cooperative pushing from below and multi-center bonding

Abstract

Actinide-ligand bonds with high multiplicities remain poorly understood. Decades ago, an effect known as 6p pushing from below (PFB) was proposed to enhance actinide covalency. A related effect—also poorly understood—is inverse trans influence (ITI). The present computational study of actinide-ligand covalent interactions with high bond multiplicities quantifies the energetic contributions from PFB and identifies a hitherto overlooked fourth bonding interaction for 2nd-row ligands in the studied organometallic systems. The latter are best described by a terminal O/N ligand exhibiting quadruple bonding interactions with the actinide. The 4th interaction may be characterized as a multi-center or charge-shift bond involving the trans ligand. It is shown in this work that the 4th bonding interaction is a manifestation of ITI, assisted by PFB, and provides a long-sought missing piece in the understanding of actinide chemistry.

10-Valence-Electron C≡O and the 14-VE C≡Pt: Two Triple-Bonded Isoelectronic Families Differing by a dδ4 Ring

“…The OUIr + was prepared by Santos et al For reviews on uranyl analog complexes, see Wei et al, or Maria and Marçalo . A closer analysis of UA multiple bonding was given by Motta and Autschbach …”

Understanding the Complexation Behavior of Carbamoylphosphine Oxide Ligands with Representative f-Block Elements

“…In earlier investigations, density functional theory (DFT) methods were employed to deduce geometric configurations, and their effectiveness in elucidating experimental observations has been proven. − In this context, geometries of all of the complexes in the present study were optimized in the gas phase at the DFT level using the BP86 , density functional in conjunction with the def2-TVZP basis set. , For the heavy elements, an effective core potential (ECP) generated for a neutral atom with quasi-relativistic methods , was used to replace the inner-shell electrons (28 and 60 electrons for lanthanides and actinides, respectively). The rest of the electrons were explicitly treated using the standard def2-TZVP basis set.…”

f-Element Zintl Chemistry: Actinide-Mediated Dehydrocoupling of H2Sb1– Affords the Trithorium and Triuranium Undeca-Antimontriide Zintl Clusters [{An(TrenTIPS)}3(μ3-Sb11)] (An = Th, U; TrenTIPS = {N(CH2CH2NSiiPr3)3}3–)

“…The Quantum Theory of Atoms in Molecules analysis , was carried out within the ADF program. We quote Nalewajski–Mrozek bond orders since they reproduce expected bond multiplicities reliably in polar heavy atom structures whereas Mayer bond orders for polar bonds often do not conform with chemical intuition . The ADF-GUI (ADFview) was used to prepare three-dimensional plots of the electron density.…”