Activation of Strong π-Acids at [FeS] Clusters Enabled by a Noncanonical Electronic Structure.

Although Fe-S clusters are privileged metallocofactors for the reduction of N, CO, and other π-acidic substrates, their constituent metal ions─high-spin Fe and Fe─are typically not amenable to binding and activating strong π-acids. Here, we demonstrate that [FeS] clusters can overcome this limitation by adopting a noncanonical electronic structure. Specifically, we report the synthesis and characterization of a series of 3:1 site-differentiated [FeS] clusters in which the unique Fe site is bound by one of 10 electronically variable arylisocyanide ligands.

All-Optical Control of Bubble and Skyrmion Breathing.

Controlling the dynamics of topologically protected spin objects by all-optical means promises enormous potential for future spintronic applications. Excitation of bubbles and skyrmions in ferrimagnetic [Fe(0.35  nm)/Gd(0.

Steerable current-driven emission of spin waves in magnetic vortex pairs.

The efficient excitation of spin waves is a key challenge in the realization of magnonic devices. We demonstrate current-driven generation of spin waves in antiferromagnetically coupled magnetic vortices. We use time-resolved x-ray microscopy to directly image the emission of spin waves upon the application of alternating currents flowing directly through the magnetic stack.

A general method for metallocluster site-differentiation.

The deployment of metalloclusters in applications such as catalysis and materials synthesis requires robust methods for site-differentiation: the conversion of clusters with symmetric ligand spheres to those with unsymmetrical ligand spheres. However, imparting precise patterns of site-differentiation is challenging because, compared with mononuclear complexes, the ligands bound to clusters exert limited spatial and electronic influence on one another. Here, we report a method that employs sterically encumbering ligands to bind to only a subset of a cluster's coordination sites.