Bridging The Gap: Rotational Study Of H2 In Complexes With Small Aromatic Molecules

Dohmen, Robin

Permalink

https://hdl.handle.net/2142/116756 Copy

Description

Title

Bridging The Gap: Rotational Study Of H2 In Complexes With Small Aromatic Molecules

Author(s)

Dohmen, Robin

Contributor(s)

• Obenchain, Daniel A.
• Pinacho, Pablo
• Schnell, Melanie

Issue Date

2022-06-24

Keyword(s)

Mini-symposium: Benchmarking in Spectroscopy

Abstract

Molecular hydrogen plays a key role in our efforts to shift our energy production to renewable resources. Hydrogen is an important energy storage molecule which in the future may replace our fossilized fuels as a transportable energy source. To appropriately model hydrogen storage materials, an understanding of the fundamental binding to organic systems is required. In previous works only a few inorganic and metallic complexes with hydrogen have be investigated by rotational spectroscopy.\footnote{Jäger, W. et al., \textit{J. Chem. Phys.}, \textbf{127} 054305, 2007, DOI: 10.1063/1.2756534 }$^,$\footnote{Obenchain, D., Frank, H., Pickett, H., Novik, S., \textit{J. Chem. Phys.}, \textbf{146} 204302, 2017, DOI:10.1063/1.4983042} This work aims to bridge the gap to large covalent organic frameworks (COF) by focusing on the microwave structure of hydrogen heterodimers with small aromatic ring systems.\footnote{Geng, K., He, T., Liu, R. et al., \textit{Chem. Rev.}, \textbf{120} 8814, 2020, DOI: 10.1021/acs.chemrev.9b00550} In this work the binding sites of hydrogen to halogen benzaldehydes which serve as mimics COF monomers, specifically boronic ester based COFs, are studied. These volatile systems possess a large dipole moment and provide a method of increasing the complexity of the system by the introduction of quadrupolar nuceli to finally look at small boronic esters in hydrogen complexes. Of particular interest are the differences observed for the rotational spectrum of \textit{ortho}- and \textit{para}-hydrogen and its structural impact investigated by isotopic substitution. The significant differences between these two species demonstrate there are significant differences in binding strength of \textit{o}-\chem{H_2} and \textit{p}-\chem{H_2} which are experimentally observable. Broadband rotational spectra are presented, are supplemented with cavity Fourier transform microwave spectroscopy data to resolve the additional hyperfine splitting of \textit{o}-\chem{H_2} ($j = 1$). These experimental results can be directly compared to a number of quantum chemical predictions to provide a foundation for the simulation of large scale covalent organic frameworks.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

text

Language

eng

Handle URL

https://hdl.handle.net/2142/116756

DOI

https://doi.org/10.15278/isms.2022.FB06

Copyright and License Information

Copyright 2022 held by the authors

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