Controlling Through‐Space and Through‐Bond Exchange Pathways in Bis‐Cobaltocenes for Molecular Spintronics

Abstract

Pinching molecules via chemical strain suggests intuitive consequences, such as compression at the pinched site, and clothespin‐like opening of other parts of the structure. If this opening affects two spin centers, it should result in reduced communication between them. We show that for naphthalene‐bridged biscobaltocenes with competing through‐space and through‐bond pathways, the consequences of pinching are far less intuitive: despite the known dominance of through‐space interactions, the bridge plays a much larger role for exchange spin coupling than previously assumed. Based on a combination of chemical synthesis, structural, magnetic and redox characterization, and a newly developed first‐principles theoretical pathways analysis, we can suggest a comprehensive explanation for this nonintuitive behavior. These results are of interest for molecular spintronics, as naphthalene‐linked cobaltocenes can form wires on surfaces for potential spin‐only information transfer.