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arXiv · 2410.17156

Interpreting tunneling spectroscopic maps of a dinuclear Co(II) complex on gold

Roberto Robles·Chao Li·Sara Realista·Paulo Nuno Martinho·Manuel Gruber·Alexander Weismann·Nicolás Lorente·Richard Berndt
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Abstract

Scanning tunneling microscope data from a dinuclear Co(II) complex adsorbed on Au(111) are analysed using density functional theory calculations. We find that the interaction with the substrate substantially changes the geometry of the non-planar molecule. Its electronic states, however, remain fairly similar to those calculated for a gas-phase molecule. The calculations reproduce intriguing contrasts observed in experimental maps of the differential conductance dI/dV and reveal the relative importance of geometric and electronic factors that impinge on the image contrasts. For a meaningful comparison, it is important that the calculations closely mimic the experimental mode of measurement.

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Roberto Robles, Chao Li, Sara Realista, Paulo Nuno Martinho, Manuel Gruber, Alexander Weismann, Nicolás Lorente, Richard Berndt. 2024-10-22. Interpreting tunneling spectroscopic maps of a dinuclear Co(II) complex on gold. https://doi.org/10.1103/physrevb.111.085409

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