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Updated: Jun 19, 2026

Chemical Vapor Deposition of an Organic Magnet, Vanadium Tetracyanoethylene
Published on: July 3, 2015
Tuning molecule-mediated spin coupling in bottom-up-fabricated vanadium-tetracyanoethylene nanostructures
Daniel Wegner1, Ryan Yamachika, Xiaowei Zhang
1Department of Physics, University of California, Berkeley, Berkeley, California 94720-7300, USA.
Abstract:
We have fabricated hybrid magnetic complexes from V atoms and tetracyanoethylene ligands via atomic manipulation with a cryogenic scanning tunneling microscope. Using tunneling spectroscopy we observe spin-polarized molecular orbitals as well as Kondo behavior. For complexes having two V atoms, the Kondo behavior can be quenched for different molecular arrangements, even as the spin-polarized orbitals remain unchanged. This is explained by variable spin-spin (i.e., V-V) ferromagnetic coupling through a single tetracyanoethylene (TCNE) molecule, as supported by density functional calculations.
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