Speaker: Robert K. Thomson, Assistant Professor,
Department of Chemistry and Biochemistry,
University of Oklahoma
Novel Photochemical Methods of Generating U=N Multiple Bonds
Abstract:
Multiple bonds between uranium and main-group elements are important
molecular constructs as they help to shed light on the nature of bonding in
actinides and the degree of involvement of f-orbitals in such species. Uranium
nitrides (U¡ÔN) are
particularly fascinating multiply-bonded fragments as they have relevance to
the nuclear fuel cycle, where ceramic uranium nitrides (UN)x have been
proposed as new advanced nuclear fuels that can replace traditional
mixed-oxide (MOX) type fuel formulations. For these reasons, synthetic models
of these U¡ÔN complexes have been long sought after targets, with success
only being achieved very recently. This presentation will describe our
application of photochemistry to generate the first terminal uranium nitride
complex and its subsequent C-H bond activation chemistry and spectral
properties. Our
investigations have also uncovered a new photochemically-induced U-N bond
cleavage process that results in U=N double bond formation. Our application
of photochemistry to the synthesis of rare actinide species is a fundamentally
new approach, and these results have inspired others to begin applying
photochemical approaches to actinide science.