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arXiv · 0707.1045

Long-range repulsive interaction between TTF molecules on a metal surface induced by charge transfer

I. Fernandez-Torrente·S. Monturet·K. J. Franke·J. Fraxedas·N. Lorente·J. I. Pascual
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Abstract

The low-coverage adsorption of a molecular electron donor, tetrathiafulvalene, on Au(111) is characterized by the spontaneous formation of superlattice of monomers, whose spacing exceeds the equilibrium distance of non-covalent interactions and depends on coverage. The origin of this peculiar growth mode is due to a long-range repulsive interaction between molecules. The analysis of molecular-pair distributions obtained by scanning tunneling microscopy measurements permits us to determine that the nature of TTF intermolecular interactions on Au (111) is electrostatic. A repulsion between molecules is caused by the accumulation of charge due to electron donation into the metal surface, as pictured through density functional theory calculations.

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I. Fernandez-Torrente, S. Monturet, K. J. Franke, J. Fraxedas, N. Lorente, J. I. Pascual. 2007-07-06. Long-range repulsive interaction between TTF molecules on a metal surface induced by charge transfer. https://doi.org/10.1103/physrevlett.99.176103

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