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arXiv · 0907.0490

Tuning Molecule-Mediated Spin Coupling in Bottom-Up Fabricated Vanadium-TCNE Nanostructures

Daniel Wegner·Ryan Yamachika·Xiaowei Zhang·Yayu Wang·Tunna Baruah·Mark R. Pederson·Bart M. Bartlett·Jeffrey R. Long·Michael F. Crommie
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Abstract

We have fabricated hybrid magnetic complexes from V atoms and tetracyanoethylene (TCNE) 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 TCNE molecule, as supported by density functional calculations.

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Daniel Wegner, Ryan Yamachika, Xiaowei Zhang, Yayu Wang, Tunna Baruah, Mark R. Pederson, Bart M. Bartlett, Jeffrey R. Long, Michael F. Crommie. 2009-07-02. Tuning Molecule-Mediated Spin Coupling in Bottom-Up Fabricated Vanadium-TCNE Nanostructures. https://doi.org/10.1103/physrevlett.103.087205

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