Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Chemical Bonding

Plutonium joins the carbene club

Researchers report first plutonium-carbon multiple bonds, illuminating periodic trends

by Brianna Barbu
February 15, 2024

 

A three-dimensional model of a complex with two N-heterocyclic carbenes and one alkylidene-containing pincer ligand bonded to a central plutonium atom.
Credit: Steve Liddle
Researchers have made plutonium complexes boasting alkylidene and N-heterocyclic carbene ligands.

Scientists from the University of Manchester and Los Alamos National Laboratory have reported the first-ever plutonium carbenes (J. Am. Chem. Soc. 2024, DOI: 10.1021/jacs.3c12719) . Besides being the first experimentally verified example of a Pu–C double bond, the three new complexes help establish how plutonium’s bonding and reactivity habits compare to other f-block elements.

Theoretical predictions say that actinides should become more ionic moving from left to right, but ”there’s no substitute for going out and actually seeing that it’s true” in the lab, says Steve Liddle of the University of Manchester, who led the work. The bonds between carbenes and metal atoms have a high covalent character, which makes them a good way to assess how covalent an element’s bonding can be.

Plutonium is rare and radioactive, so the researchers had to make the molecules in a special facility at Los Alamos and carefully plan their experiments to get the most possible information out of small amounts of material. Using crystallography and spectroscopy, they verified the structures and compared their bond lengths and reactivity to analogous complexes of uranium, neptunium, and lanthanides with similar atomic radii and electronic structures. Based on the comparisons, they found that plutonium’s bonding to the alkylidene and N-heterocyclic carbene ligands was more covalent than predicted, hinting that f-block elements’ behavior isn’t quite as clear-cut as theory might suggest.

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.