A5105931348- Advanced Chemical Physics Studies
- Mass Spectrometry Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- Atmospheric Ozone and Climate
- Spectroscopy and Laser Applications
- Atmospheric chemistry and aerosols
- Atomic and Molecular Physics
- Molecular spectroscopy and chirality
- Photochemistry and Electron Transfer Studies
- Catalysis and Oxidation Reactions
- Laser-Matter Interactions and Applications
- Molecular Spectroscopy and Structure
- Catalytic Processes in Materials Science
- Estrogen and related hormone effects
- Electron and X-Ray Spectroscopy Techniques
- Surface Chemistry and Catalysis
- Astrophysics and Star Formation Studies
- Inorganic Fluorides and Related Compounds
- Photoreceptor and optogenetics research
- X-ray Spectroscopy and Fluorescence Analysis
- Origins and Evolution of Life
- Porphyrin and Phthalocyanine Chemistry
- Inorganic and Organometallic Chemistry
- Astro and Planetary Science
- Molecular Junctions and Nanostructures
Synchrotron soleil
2016-2025
Inter-American Development Bank
2022
Impact
2022
University of Nottingham
2001-2020
Instituto de Física Fundamental
2011-2020
Moorabbin Hospital
2019
University of Chile
2019
Osservatorio Astronomico di Cagliari
2014
Université Paris-Sud
2003-2013
Centre National de la Recherche Scientifique
2005-2013
We present an inversion method called pBasex aimed at reconstructing the original Newton sphere of expanding charged particles from its two-dimensional projection by fitting a set basis functions with known inverse Abel integral. The have been adapted to polar symmetry photoionization process optimize energy and angular resolution while minimizing CPU time response cartesian noise that could be given detection system. presented here only applies systems unique axis although it can overcome...
DESIRS is a new undulator-based VUV beamline on the 2.75 GeV storage ring SOLEIL (France) optimized for gas-phase studies of molecular and electronic structures, reactivity polarization-dependent photodynamics model or actual systems encountered in universe, atmosphere biosphere. It equipped with two dedicated endstations: Fourier-transform spectrometer (FTS) ultra-high-resolution absorption spectroscopy (resolving power up to 10(6)) an electron/ion imaging coincidence spectrometer. The...
We present a versatile double imaging particle coincidence spectrometer operating in fully continuous mode, named DELICIOUS III, which combines velocity map device and modified Wiley-McLaren time of flight momentum analyzer for photoelectrons photoions, respectively. The is installed permanent endstation on the DESIRS vacuum ultraviolet (VUV) beamline at French National Synchrotron Radiation Facility SOLEIL, dedicated to gas phase VUV spectroscopy, photoionization, molecular dynamics...
We studied the photoionization of 2-pyridone and its tautomer, 2-hydroxypyridine by means VUV synchrotron radiation coupled to a velocity map imaging electron/ion coincidence spectrometer. The efficiency (PIE) spectrum is composed steps. state energies [2-pyridone]+ cation in ground à excited electronic states, as well [2-hydroxypyridine]+ state, are determined. slow photoelectron spectra (SPES) dominated 000 transitions corresponding states together with several weaker bands population pure...
Electron–nuclei coupling accompanying excitation and relaxation processes is a fascinating phenomenon in molecular dynamics. A striking unexpected example of such presented here the context photoelectron circular dichroism measurements on randomly oriented, chiral methyloxirane molecules, unaffected by any continuum resonance. Here, we report that forward-backward asymmetry electron angular distribution, with respect to photon axis, which associated can surprisingly reverse direction...
We report here the recent upgrade of SAPHIRS permanent photoionization end-station at DESIRS vacuum ultraviolet beamline synchrotron SOLEIL, whose performances have been enhanced by installing an additional double-skimmer differential chamber. The smaller molecular beam profile obtained interaction region has increased mass resolution double imaging photoelectron photoion coincidence (i(2)PEPICO) spectrometer, DELICIOUS III, installed in chamber endstation, a factor two, to M/ΔM ∼ 1700...
Photoelectron circular dichroism (PECD) manifests itself as an intense forward/backward asymmetry in the angular distribution of photoelectrons produced from randomly-oriented enantiomers by photoionization with circularly-polarized light (CPL). As a sensitive probe both dynamics and chiral molecular potential, PECD attracts much interest especially recent performance related experiments visible VUV laser sources. Here we report, use quasi-perfect CPL synchrotron radiation using double...
We present a photoelectron-photoion coincidence (PEPICO) spectrometer named DELICIOUS II which combines velocity map imaging apparatus with Wiley–McLaren time of flight analyzer for the study gas phase samples in interaction synchrotron radiation (SR). This versatile system is capable providing photoelectron images on mass-selected compounds kinetic energy resolutions ΔE/E=5% and 17 eV bandwidth, as well threshold spectra measured resolution 0.8 meV, demonstrated 3p−1 ionization argon....
ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTRegiospecific aldol condensations of the kinetic lithium enolates methyl ketonesGilbert Stork, George A. Kraus, and Gustavo GarciaCite this: J. Org. Chem. 1974, 39, 23, 3459–3460Publication Date (Print):November 1, 1974Publication History Published online1 May 2002Published inissue 1 November 1974https://pubs.acs.org/doi/10.1021/jo00937a054https://doi.org/10.1021/jo00937a054research-articleACS PublicationsRequest reuse permissionsArticle...
Threshold photoelectron spectra (TPES) of the isotopomers methyl radical (CH3, CH2D, CHD2, and CD3) have been recorded in 9.5−10.5 eV VUV photon energy range using third generation synchrotron radiation to investigate vibrational spectroscopy corresponding cations at a 7−11 meV resolution. A threshold photoelectron−photoion coincidence (TPEPICO) spectrometer based on velocity map imaging Wiley−McLaren time-of-flight has used simultaneously record TPES several species produced Ar-seeded beam...
Measuring the ultrafast dynamics of chiral molecules in gas phase has been a long standing and challenging quest molecular physics. The main limitation to reach that goal lack highly sensitive chiroptical measurement. By enabling discrimination with up several 10% sensitivity, photoelectron circular dichroism (PECD) offers solution this issue. However, tracking processes requires measuring PECD ultrashort light pulses. Here we compare obtained different sources, from extreme ultraviolet...
Complex reactive processes in the gas phase often proceed via numerous reaction steps and intermediate species that must be identified quantified to develop an understanding of pathways establish suitable mechanisms. Here, photoelectron-photoion coincidence (PEPICO) spectroscopy has been applied analyse combustion intermediates present a premixed fuel-rich (ϕ = 1.7) ethene-oxygen flame diluted with 25% argon, burning at reduced pressure 40 mbar. For first time, multiplexing...
We present a microwave discharge flow tube coupled with double imaging electron/ion coincidence device and vacuum ultraviolet (VUV) synchrotron radiation. The system has been applied to the study of photoelectron spectroscopy well-known radicals OH OD. scheme provides high selectivity yields spectra pure radicals, removing ever-present contributions from excess reactants, background, or secondary products, therefore obviating need for prior knowledge all possible byproducts. encompassing...
The methanol-to-hydrocarbons (MTH) process is an industrially relevant method to produce valuable light olefins such as propylene. One of the ways enhance propylene selectivity modify zeolite catalysts with alkaline earth cations. underlying mechanistic aspects this type promotion are not well understood. Here, we study interaction Ca2+ reaction intermediates and products formed during MTH reaction. Using transient kinetic spectroscopic tools, find strong indications that differences between...
Circular dichroism in the angular distribution of valence photoelectrons emitted from randomly oriented chiral molecules has been observed experiments that use circularly polarized VUV synchrotron radiation. Photoionization outermost carbonyl oxygen lone pair electrons pure enantiomers prototype molecule camphor is shown to have an asymmetry forward–backward scattering (relative propagation direction light beam) magnitude approaching 3% at 9.2 eV photon energy. The reverses on exchange...
An electron imaging technique has been used to study the full angular distribution of valence photoelectrons produced from enantiomerically pure molecular beams camphor when these are photoionized with circularly polarized light. In addition familiar beta parameter, this provides a new chiral term, taking form an additional cosine function in which consequently displays forward-backward ejection asymmetry. Several ionization channels have studied using synchrotron radiation 8.85-26 eV photon...
Gas phase studies of biological molecules provide structural and dynamical information on isolated systems. The lack inter- or intra-molecular interactions facilitates the interpretation experimental results through theoretical calculations, constitutes an informative complement to condensed phase. However advances in field are partially hindered by difficulty vaporising these systems, most which thermally unstable. In this work we present a newly developed aerosol mass thermodesorption...
The valence shell photoionization of the simplest proteinaceous chiral amino acid, alanine, is investigated over vacuum ultraviolet region from its ionization threshold up to 18 eV. Tunable and variable polarization synchrotron radiation was coupled a double imaging photoelectron/photoion coincidence (i2PEPICO) spectrometer produce mass-selected photoelectron spectra derive state-selected fragmentation channels. circular dichroism (PECD), an orbital-sensitive, conformer-dependent chiroptical...
We report the first experimental measurement of near-threshold photo-ionization spectra polycyclic aromatic hydrocarbon clusters made pyrene C16H10 and coronene C24H12, obtained using imaging photoelectron photoion coincidence spectrometry with a VUV synchrotron beamline. The results ionization energy are confronted to calculated ones from simulations dedicated electronic structure treatment for large ionized molecular clusters. Experiment theory consistently find decrease cluster size....
Chiral molecules are widespread in nature, playing a fundamental role bio-chemical processes and the origin of life itself. The observation dynamics chiral is crucial for understanding control activity photo-excited states. One most promising techniques study systems time-resolved photoelectron circular dichroism (TR-PECD), which offers an intense sensitive probe vibronic geometric molecular structure as well electronic structures, their evolution on femtosecond timescale. However, non-local...
The inner-shell photoionization of unoriented camphor molecules by circularly polarized light has been investigated from threshold to a photoelectron kinetic energy approximately 65 eV. Photoelectron spectra the carbonyl C 1s orbital, recorded at magic angle 54.7 degrees with respect propagation direction, show an asymmetry up 6% on change either photon helicity or molecular enantiomer. These observations reveal circular dichroism in resolved emission between forward and backward scattering...