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arXiv · 1908.05933

Vibrational signatures of diamondoid dimers with large intramolecular London dispersion interactions

Christoph Tyborski·Tobias Hueckstaedt·Roland Gillen·Tommy Ott·Nataylia A. Fokina·Andrey A. Fokin·Peter R. Schreiner·Janina Maultzsch
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Abstract

We analyze the vibrational properties of diamondoid compounds via Raman spectroscopy. The compounds are interconnected with carbon-carbon single bonds that exhibit exceptionally large bond lengths up to 1.71 A. Attractive dispersion interactions caused by well-aligned intramolecular H--H contact surfaces determine the overall structures of the diamondoid derivatives. The strong van-der-Waals interactions alter the vibrational properties of the compounds in comparison to pristine diamondoids. Supported by dispersion-corrected density functional theory (DFT) computations, we analyze and explain their experimental Raman spectra with respect to unfunctionalized diamondoids. We find a new set of dispersion-induced vibrational modes comprising characteristic CH/CH$_{2}$ vibrations with exceptionally high energies. Further, we find structure-induced dimer modes that are indicative of the size of the dimers.

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Christoph Tyborski, Tobias Hueckstaedt, Roland Gillen, Tommy Ott, Nataylia A. Fokina, Andrey A. Fokin, Peter R. Schreiner, Janina Maultzsch. 2019-08-16. Vibrational signatures of diamondoid dimers with large intramolecular London dispersion interactions. https://arxiv.org/abs/1908.05933

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