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Updated: May 12, 2026

Exploring the Radical Nature of a Carbon Surface by Electron Paramagnetic Resonance and a Calibrated Gas Flow
Published on: April 24, 2014
Surface-Supported Hydrocarbon π Radicals Show Kondo Behavior
Stefan Müllegger1, Mohammad Rashidi, Michael Fattinger
1Institute of Semiconductor and Solid State Physics, Johannes Kepler University Linz , Altenberger Strasse 69, 4040 Linz, Austria.
Abstract:
Stable hydrocarbon radicals are utilized as spin standards and prototype metal-free molecular magnets able to withstand ambient conditions. Our study presents experimental results obtained with submolecular resolution by scanning tunneling microscopy and spectroscopy from monomers and dimers of stable hydrocarbon π radicals adsorbed on the Au(111) surface at 7-50 K. We provide conclusive evidence of the preservation of the radical spin-1/2 state, aiming to establish α,γ-bisdiphenylene-β-phenylallyl (BDPA) on Au(111) as a novel Kondo system, where the impurity spin is localized in a metal-free π molecular orbital of a neutral radical state in gas phase preserved on a metal support.
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