Focused electron beam-induced deposition from Ru(CO)₄(fumaronitrile): incomplete carbonyl loss and nitrogen retention.

UNLABELLED: The additive manufacturing of metal nanostructures using direct-write focused electron beam-induced deposition (FEBID) requires exploration and development of new metal-coordinated precursor complexes. In this study, we introduce (η 2-fumaronitrile)(tetracarbonyl)ruthenium(0), a novel FEBID precursor designed using a mechanism-based approach in which the ligand set consists of neutral two-electron donor ligands weakly bound to the metal centre atom. Nanostructures were fabricated using this precursor via FEBID, and their elemental composition was determined through energy-dispersive X-ray spectroscopy. The resulting deposits consistently exhibited a metal content in the range of 8-12 at.%, highlighting the need for a deeper understanding of the role of competing mechanisms preventing detached neutral ligands from desorption during the FEBID process. GRAPHICAL ABSTRACT: Fate of (η 2-fumaronitrile)(tetracarbonyl)ruthenium in the focused electron-beam induced deposits. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1140/epjd/s10053-026-01225-9.