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arXiv · 1508.01135

Bound excitons and many-body effects in x-ray absorption spectra of azobenzene-functionalized self-assembled monolayers

Caterina Cocchi·Claudia Draxl
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Abstract

We study x-ray absorption spectra of azobenzene-functionalized self-assembled monolayers (SAMs), investigating excitations from the nitrogen K edge. Azobenzene with H-termination and functionalized with CF3 groups is considered. The Bethe-Salpeter equation is employed to compute the spectra, including excitonic effects, and to determine the character of the near-edge resonances. Our results indicate that core-edge excitations are intense and strongly bound: Their binding energies range from about 6 to 4 eV, going from isolated molecules to densely-packed SAMs. Electron-hole correlation rules these excitations, while the exchange interaction plays a negligible role.

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Caterina Cocchi, Claudia Draxl. 2015-11-05. Bound excitons and many-body effects in x-ray absorption spectra of azobenzene-functionalized self-assembled monolayers. https://doi.org/10.1103/physrevb.92.205105

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