Stefan S. Rudel

NOUF6 Revisited: A Comprehensive Study of a Hexafluoridouranate(V) Salt

We have synthesized NOUF6 by direct reaction of NO with UF6 in anhydrous HF (aHF). Based on the unit cell volume and powder diffraction data, the compound was previously reported to be isotypic to O2 PtF6 , however, detailed structural data, such as the atom positions and all information that can be derived from those, were unavailable. We have therefore investigated the compound by using single-crystal and powder X-ray diffraction, IR, Raman, NMR, EPR, and photoluminescence spectroscopy, magnetic measurements, as well as chemical analysis, density determination, and quantum chemical calculations.

A 1D Coordination Polymer of UF5 with HCN as a Ligand

β-Uranium(V) fluoride was reacted with liquid anhydrous hydrogen cyanide to obtain a 1D coordination polymer with the composition 1∞ [UF5 (HCN)2 ], 1∞ [UF4/1 F2/2 - (HCN)2/1 ], revealed by single-crystal X-ray structure determination. The reaction system was furthermore studied by means of vibrational and NMR spectroscopy, as well as by quantum chemical calculations. The compound presents the first described polymeric HCN Lewis adduct and the first HCN adduct of a uranium fluoride.

Recent advances in the chemistry of uranium halides in anhydrous ammonia

Abstract This article presents an overview of recent advancements in the field of uranium chemistry, paying special attention to the preparation of starting materials and to the chemistry of uranium halides in liquid ammonia. Where suitable, insights into the chemistry of thorium are also presented. Herein, we report upon the crystal structures of several ammine complexes as well as their deprotonation products. Specific examples of hydrolysis products in liquid ammonia are showcased. Additionally, advancements in the preparation of uranium cyanides are presented.

Nanosized Gadolinium and Uranium—Two Representatives of High-Reactivity Lanthanide and Actinide Metal Nanoparticles

Gadolinium (Gd0) and uranium (U0) nanoparticles are prepared via lithium naphthalenide ([LiNaph])-driven reduction in tetrahydrofuran (THF) using GdCl3 and UCl4, respectively, as low-cost starting materials. The as-prepared Gd0 and U0 suspensions are colloidally stable and contain metal nanoparticles with diameters of 2.5 ± 0.7 nm (Gd0) and 2.0 ± 0.5 nm (U0). Whereas THF suspensions are chemically stable under inert conditions (Ar and vacuum), nanoparticulate powder samples show high reactivity in contact with, for example, oxygen, moisture, alcohols, or halogens. Such small and highly reactive Gd0 and U0 nanoparticles are first prepared via a dependable liquid-phase synthesis and stand as representatives for further nanosized lanthanides and actinides.

Formation and Properties of the Trichloroberyllate Ion

The activation of C-Cl bonds in dichloromethane and chloroform was observed by BeCl2 in the presence of PMe3 and PCy3. This leads to the formation of [Me3PCH2Cl]Cl and [Cy3PCHCl2][BeCl3]. The latter compound is the first example of a tricoordinated beryllium species with nonbulky ligands and proof of the existence and stability of the long-predicted [BeCl3]- ion. In analogy to the isoelectronic BCl3, the trichloroberyllate anion exhibits Lewis acidic behavior toward electron-pair donors and was probed for the electronic and steric influence of the Lewis base. [BeCl3]- can also act as a chloride ion donor or acceptor, leading to the formation of neutral phosphane adducts to BeCl2 and [BeCl4]2-. The existing equilibria between these species were investigated and showed high chloride mobility.