Laurent Nahon

Aryl radical addition–dehydrocyclization drives rapid polycyclic aromatic hydrocarbon growth

Shane J. Goettl, Bing‐Jian Sun, Andrew Martin Turner, Myriam Drissi et autres

Polycyclic aromatic hydrocarbons are ubiquitous in space, yet astrochemical models fail to reproduce their observed abundances because known growth mechanisms are far too slow. Here, we report a plausible pathway for rapid polycyclic aromatic hydrocarbon mass growth mediated by multi-ring aryl radicals …

us, tw, fr (code pays fourni par la source)

Vacuum-ultraviolet photoionization of a grandPAH molecule

Helgi Rafn Hróðmarsson, Ugo Jacovella, Serge Pluta, Xuelin Yao et autres

Context . So-called grandPAH molecules are proposed to be omnipresent in various interstellar regions as they are large enough to be photostable against strong interstellar radiation fields. They are also notoriously difficult to synthesize and sublimate. Measuring their gas phase spectra and …

fr, de, nl, us, pl, cz (code pays fourni par la source)

Spectroscopy and Conformer‐Selective Photoelectron Circular Dichroism of Chiral Molecules

Laurent Nahon, Anne Zehnacker

Like most chiroptical spectroscopy techniques, photoelectron circular dichroism (PECD), that is, the forward-backward asymmetry in the angular distribution of the electron resulting from the ionization of a chiral molecule by a circularly polarized light, is very sensitive to structural changes, in particular …

fr (code pays fourni par la source)

Dissociative Single and Double Ionization of Pyridine

Sitanath Mondal, Brendan Wouterlood, Gustavo A. García, Laurent Nahon et autres

Dissociative ionization processes of simple heterocyclic molecules like pyridine are relevant for an understanding of radiation damage processes in biological material that occur naturally in complex condensed environments. Pyridine can thereby be considered a simple analogue of nucleobases and related ring structures …

Dissociative Single and Double Ionization of Pyridine

Sitanath Mondal, Brendan Wouterlood, Gustavo A. García, Laurent Nahon et autres

Dissociative ionization processes of simple heterocyclic molecules like pyridine are relevant for an understanding of radiation damage processes in biological material that occur naturally in complex condensed environments. Pyridine can thereby be considered a simple analogue of nucleobases and related ring structures …

de, fr (code pays fourni par la source)

Angle-resolved photoelectron spectroscopy of the DABCO molecule probed with VUV radiation

Audrey Scognamiglio, Lou Barreau, Constant A. Schouder, D. Cubaynes et autres

We report a study of the diazabicyclo[2.2.2]octane (DABCO) molecule photoionized using VUV synchrotron radiation in combination with an ion--electron coincidence spectrometer. We determine accurately the adiabatic ionization energy to $7.199\pm0.006$~eV. Two vibrational progressions of DABCO cation ground state are resolved at $847~\text{cm}^{-1}\pm27~\text{cm}^{-1}$ …

Angle-resolved photoelectron spectroscopy of the DABCO molecule probed with VUV radiation

Audrey Scognamiglio, Lou Barreau, Constant A. Schouder, D. Cubaynes et autres

We report a study of the diazabicyclo[2.2.2]octane (DABCO) molecule photoionized using VUV synchrotron radiation in combination with an ion--electron coincidence spectrometer. We determine accurately the adiabatic ionization energy to $7.199\pm0.006$~eV. Two vibrational progressions of DABCO cation ground state are resolved at $847~\text{cm}^{-1}\pm27~\text{cm}^{-1}$ …

fr (code pays fourni par la source)

Linking photoelectron circular dichroism to the asymmetric total photoemission yield measured in aerosol nanoparticles of tyrosine

Sebastian Hartweg, Dušan K. Božanić, Gustavo Garcia-Macias, Laurent Nahon

Spectroscopic techniques that are sensitive to molecular chirality are important analytical tools to quantitatively determine enantiomeric excess and purity of chiral molecular samples. Many chiroptical processes however produce weak enantio-specific asymmetries due to their origin relying on weak magnetic dipole or electric …

de, fr, rs (code pays fourni par la source)

Gas-phase spectroscopy of chiral molecules

Etienne Rouquet, Valéria Lepère, Laurent Nahon, Garcia, Gustavo, A et autres

International audience

fr (code pays fourni par la source)

Dissociation and Cooling Dynamics of 2-cyanoindene Monocations: Survival of Small PAHs in Harsh Interstellar Radiation Fields

Arun Subramani, James Flotte de Pouzols, Paul Martini, José E. Navarro Navarrete et autres

Abstract The molecule, 2-cyanoindene, C 10 H 7 N (2CNI) is the only cyanosubstituted polycyclic aromatic hydrocarbon (PAH) detected in space, for which the hydrocarbon counterpart, indene, has also been observed in the same astrochemical environment—the molecular cloud TMC-1. In this study, …

Formation and transfer of HCl in a macromolecular noncovalent complex: does the roaming atom mechanism play a role?

Min Liu, Marwa Abdelmouleh, Alexandre Giuliani, Laurent Nahon et autres

In the last twenty years, the "roaming atom" mechanism emerged and gained enormous interest thanks to its success in explaining experimental results that are not accounted for by the widely accepted statistical transition state theory. However, despite intense efforts for describing this …

fr (code pays fourni par la source)

Dissociative single and double ionization of pyridine

Sitanath Mondal, Brendan Wouterlood, Gustavo A. García, Laurent Nahon et autres

Dissociative ionization processes of simple heterocyclic molecules like pyridine are relevant for an understanding of radiation damage processes in biological material that occur naturally in complex condensed environments. Pyridine can thereby be considered a simple analogue of nucleobases and related ring structures …

de, fr (code pays fourni par la source)