Theoretical Search for Very Short Metal–Actinide Bonds: NUIr and Isoelectronic Systems

Abstract

Cumulated triple bonds: A new class of molecules, the isoelectronic series of NUIr, (depicted) has been postulated and theoretically studied. The bond between the actinide and the 5d‐metal atom is very short and is shown to correspond to triple bonding. The NU bond is also a triple bond.

Additive Covalent Radii for Single-, Double-, and Triple-Bonded Molecules and Tetrahedrally Bonded Crystals: A Summary

“…The uranyl-type series included members of the monosubstituted OUIr + series. The latter isoelectronic family was predicted 88 and subsequently observed. 89 The triple-bond character of the uranyl ion OUO 2+ is explained by its electron configuration 90 π π σ σ …”

Formation of unprecedented actinidecarbon triple bonds in uranium methylidyne molecules

“…Whereas numerous organic and inorganic compounds with multiple bonds are known (7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17), f elements (lanthanides and actinides) with multiple bonds are relatively rare, except for early actinides. Such bonding has aroused great interest recently in the search for actinide complexes with multiple bonds between two actinide metals (18)(19)(20)(21) and between actinide (An) and main-group ligands (L) (22)(23)(24)(25)(26)(27)(28).…”

On the Extreme Oxidation States of Iridium

“…Although the atomic charges at the metal atoms M are much more modest, the electronic structures of the M(CO) 3 ‐type systems correspond to the 18 e ideas. Neither these systems, nor the diatomic predicted LaIr, nor the triatomic predicted29 NUIr conflict with the nominal oxidation state of Ir −III .…”

“… Although the atomic charges at the metal atoms M are much more modest, the electronic structures of the M(CO) 3 ‐type systems correspond to the 18 e ideas. Neither these systems, nor the diatomic predicted LaIr, nor the triatomic predicted29 NUIr conflict with the nominal oxidation state of Ir −III . There may exist several so far unknown closed‐shell triple‐bonded32 neutral MM′ or M′M′ dimers of M = {Sc, Y, La–Lu}, M′ = {N–Bi; Co–Ir}, and the isoelectronic ions. The question of “metallic self‐oxidation”, that is, apparent cationic Mössbauer isomer shifts in metals and alloys, due to electron transfer to the conduction band, may deserve further study. This includes the common reference substances. …”

“…The idea here was that, at the end of a multiple bond, Ir behaves like N, just like Pt behaves like O 28. The NUIr species is analogous with the known NUN or with uranyl and was predicted by Gagliardi and Pyykkö 29. Its isoelectronic counterpart OUIr + was subsequently observed by mass spectroscopy by Santos et al 30.…”