Title :

Gas-phase hydration of nopinone: the interplay between theoretical methods and experiments unveils the conformational landscape

Author(s) :

Neeman, Elias [Auteur]
Physique Moléculaire aux Interfaces [PMI]
Avilés Moreno, Juan Ramón [Auteur]
Universidad Autónoma de Madrid [UAM]
Huet, Therese [Auteur]
Physique Moléculaire aux Interfaces [PMI]

Journal title :

Physical Chemistry Chemical Physics

Pages :

18137-18144

Publisher :

Royal Society of Chemistry

Publication date :

2021

ISSN :

1463-9076

HAL domain(s) :

Chimie/Chimie théorique et/ou physique

English abstract : [en]

The structure of microsolvated nopinone formed in the supersonic jet expansion is investigated in the gas phase. The rotational spectra of nopinone⋯(H2O)n (n = 1, 2, 3) were analysed by means of Fourier transform microwave ...
Show more >The structure of microsolvated nopinone formed in the supersonic jet expansion is investigated in the gas phase. The rotational spectra of nopinone⋯(H2O)n (n = 1, 2, 3) were analysed by means of Fourier transform microwave spectroscopy. In the present study, three monohydrates, two dihydrates and two trihydrates were observed and characterized. The observed structures are the lowest energy conformers predicted by quantum chemical calculations. In all the observed hydrates of nopinone, water was found to be linked to the ketone group (C[double bond, length as m-dash]O) with a strong hydrogen bond (ONOP⋯HW) and finishing with a dispersive one (OW⋯HNOP). The structure of nopinone was found to alter the structure of water dimer and water trimer, which make nopinone be surrounded with a chain of water molecules. A remarkable decrease in the H-bonding length was observed when the number of attached water molecules is increased. Different DFT and ab initio calculations at the equilibrium structure allowed the identification of the observed conformers. Evaluation of the B3LYP-D3 and ωB97X-D results revealed deficiencies in reproducing the structure of one observed monohydrated structure while MP2 and M06-2X reproduce all the three observed structures. A comparison with similar bicyclic ketones highlights how a small change in the bicyclic ring leads to different effects in the microsolvation of biogenic VOCs. This study presents the first step of molecular aggregation to understand the atmospheric formation of aerosols at the molecular scale.Show less >

Language :

Anglais

Popular science :

Non

ANR Project :

Physiques et Chimie de l'Environnement Atmosphérique

Collections :

• Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM) - UMR 8523

Source :

Harvested from HAL