Nano Research

, Volume 9, Issue 11, pp 3515–3527 | Cite as

Unraveling the mark of surface defects on a spinterface: The nitronyl nitroxide/TiO2(110) interface

  • Reza Kakavandi
  • Arrigo Calzolari
  • Yulia B. Borozdina
  • Prince Ravat
  • Thomas Chassé
  • Martin Baumgarten
  • M. Benedetta CasuEmail author
Research Article


Metal-free organic radicals are fascinating materials owing to their unique properties. Having a stable magnetic moment coupled to light elements makes these materials central to develop a large variety of applications. We investigated the magnetic spinterface coupling between the surface of a single rutile TiO2(110) crystal and a pyrene-based nitronyl nitroxide radical, using a combination of thickness-dependent X-ray photoelectron spectroscopy and ab initio calculations. The radicals were physisorbed, and their magnetic character was preserved on the (almost) ideal surface. The situation changed completely when the molecules interacted with a surface defect site upon adsorption. In this case, the reactivity of the defect site led to the quenching of the molecular magnetic moment. Our work elucidates the crucial role played by the surface defects and demonstrates that photoemission spectroscopy combined with density functional theory calculations can be used to shed light on the mechanisms governing complex interfaces, such as those between magnetic molecules and metal oxides.


organic spinterface photoemission spectroscopy density functional theory calculations 


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Unraveling the mark of surface defects on a spinterface: The nitronyl nitroxide/TiO2(110) interface


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Copyright information

© Tsinghua University Press and Springer-Verlag Berlin Heidelberg 2016

Authors and Affiliations

  • Reza Kakavandi
    • 1
  • Arrigo Calzolari
    • 2
  • Yulia B. Borozdina
    • 3
  • Prince Ravat
    • 3
  • Thomas Chassé
    • 1
  • Martin Baumgarten
    • 3
  • M. Benedetta Casu
    • 1
    Email author
  1. 1.Institute of Physical and Theoretical ChemistryUniversity of TübingenTübingenGermany
  2. 2.CNR-NANO Istituto NanoscienzeModenaItaly
  3. 3.Max Planck Institute for Polymer ResearchMainzGermany

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