New Actinide Chemistry and Connections to Future Nuclear Energy Challenges
Professor John Arnold (University of California, Berkeley, Department of Chemistry)
Host: Professor Michael Therien
Tuesday, October 23, 2018 - 11:40am to 1:10pm
Location: French Family Science Center 2237
Rosenthal, Janet

Link for Professor Arnold

Abstract:  The chemistry of early actinide elements continues to be a flourishing field of active research. I will present work from two areas of our current research in this area of the periodic table.

The recovery of uranium from seawater has received considerable attention in the last few years due to the size of this yet-untapped source. The world’s oceans contain 4.5 billion tons of uranium, over a thousand times more than the entire known terrestrial supply. Development of an efficient and economical technology for recovering uranium from seawater could therefore make the world’s oceans a nearly limitless source of fuel for nuclear reactors.

While a major focus has been nuclear fuel applications, the large size, oxidation state accessibility, and 5f-orbital availability in the actinides have distinguished their coordination chemistry from that of other metals in the periodic table. I will describe recent results from our laboratory concerning the synthesis and reactivity of Th and U derivatives incorporating new supporting ligands. Examples include new species featuring An—C bonds.

I will also discuss stoichiometric and catalytic reactivity of Th and U complexes supported by bis(NHC) ligands, and interesting bimetallic species of U and Th with alanate ligands.


"An overview and recent progress in the chemistry of uranium extraction from seawater." Bernard F. parker, Zhicheng Zhang, Linfeng Rao, and John Arnold.  Dalton Trans., 2018, 47, 639-644.

"Chemical structure and bonding in a thorium(III)–aluminum heterobimetallic complex." Alison B. Altman,  Alexandra C. Brown,  Guodong Rao,  Trevor D. Lohrey,  R. David Britt,  Laurent Maron,  Stefan G. Minasian,  David K. Shuh  and  John Arnold.  Chem. Sci., 2018, 9, 4317 - 4324.

"Thorium Metallacycle Facilitates Catalytic Alkyne Hydrophosphination."  Mary E. Garner , Bernard F. Parker, Stephan Hohloch, Robert G. Bergman, and John Arnold. J. Am. Chem. Soc., 2017,  DOI: 10.1021/jacs.7b08323.

"A Homoleptic Uranium(III) Tris(aryl) Complex."  Michael A. Boreen, Bernard F. Parker, Trevor D. Lohrey, and John Arnold, J. Am Chem. Soc., 2016138, 15865–15868.