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arXiv · 0809.1774

Strong polarization-induced reduction of addition energies in single-molecule nanojunctions

Kristen Kaasbjerg·Karsten Flensberg
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Abstract

We address polarization-induced renormalization of molecular levels in solid-state based single-molecule transistors and focus on an organic conjugate molecule where a surprisingly large reduction of the addition energy has been observed. We have developed a scheme that combines a self-consistent solution of a quantum chemical calculation with a realistic description of the screening environment. Our results indeed show a large reduction, and we explain this to be a consequence of both (a) a reduction of the electrostatic molecular charging energy and (b) polarization induced level shifts of the HOMO and LUMO levels. Finally, we calculate the charge stability diagram and explain at a qualitative level general features observed experimentally.

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Kristen Kaasbjerg, Karsten Flensberg. 2008-09-10. Strong polarization-induced reduction of addition energies in single-molecule nanojunctions. https://doi.org/10.1021/nl8021708

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