A5050112283- Spectroscopy and Quantum Chemical Studies
- Advanced Chemical Physics Studies
- DNA and Nucleic Acid Chemistry
- Photoreceptor and optogenetics research
- Atmospheric Ozone and Climate
- Astrophysics and Star Formation Studies
- Photochemistry and Electron Transfer Studies
- Astro and Planetary Science
- Mass Spectrometry Techniques and Applications
- Photosynthetic Processes and Mechanisms
- Analytical Chemistry and Chromatography
- Chemical and Physical Studies
- Luminescence and Fluorescent Materials
- Organic Light-Emitting Diodes Research
- Chemical Reaction Mechanisms
- Advanced Fluorescence Microscopy Techniques
- RNA and protein synthesis mechanisms
- Quantum, superfluid, helium dynamics
- Magnetic Properties and Synthesis of Ferrites
- Molecular Spectroscopy and Structure
- Fluorine in Organic Chemistry
- Advanced Condensed Matter Physics
- Multiferroics and related materials
- bioluminescence and chemiluminescence research
Stockholm University
2023-2025
Aix-Marseille Université
2024-2025
Université Paris-Saclay
2019-2024
Centre National de la Recherche Scientifique
2019-2024
Institut des Sciences Moléculaires d'Orsay
2019-2024
Physique des interactions ioniques et moléculaires
2024
The Open University
2020-2021
Centre Hospitalier d'Orsay
2019-2020
Université Paris-Sud
2019
Institut de Chimie Moléculaire et des Matériaux d'Orsay
2019
An electrospray ion source has been coupled to a cryogenic electrostatic ion-beam storage ring enable experimental studies of the fundamental properties biomolecular ions and their reactions in gas phase on longer timescales than with previous instruments. Using this equipment, we have measured vibrational radiative cooling rate deprotonated anion chromophore cyan fluorescent protein, color-shifted mutant iconic green protein. Time-resolved dissociation rates collisionally activated are...
Carbonic acid (H2CO3) is a weak relevant to astrobiology which, date, remains undetected in space. Experimental work has shown that the beta-polymorph of H2CO3 forms under space conditions through energetic (UV photon, electron, and cosmic ray) processing CO2- H2O-rich ices. We present systematic set VUV photoabsorption spectra pure mixed CO2 H2O ices exposed 1 keV electrons at 20 80 K simulate different interstellar Solar System environments. Ices were then annealed obtain layer which was...
Dipole-bound states in anions exist when a polar neutral core binds an electron diffuse orbital through charge-dipole interaction. Electronically excited cores can also bind to form Core-Excited Dipole-Bound States (CE-DBSs), which are difficult observe because they usually lie above the detachment threshold, leading very short lifetimes and, thus, unstructured transitions. We report here photodetachment spectroscopy of cryogenically cooled acetylacetonate anion (C5H7O2-) recorded by...
The UV photofragmentation spectra of cold cytosine-M+ complexes (M+: Na+, K+, Ag+) were recorded and analyzed through comparison with geometry optimizations frequency calculations the ground excited states at SCS-CC2/Def2-SVPD level theory. While in all complexes, state minimum is planar (Cs symmetry), ππ* has NH2 group slightly twisted an out-of-plane metal cation. This was confirmed by comparing simulated Franck-Condon vibrationally resolved CytNa+ CytK+. Vertical excitation transitions...
Abstract The photodynamics of protonated tryptophan and its mono hydrated complex TrpH + −H 2 O has been revisited. A combination steady‐state IR UV cryogenic ion spectroscopies with picosecond pump‐probe photodissociation experiments sheds new lights on the deactivation processes conformer‐selected complex, supported by quantum chemistry calculations at DFT coupled‐cluster levels for ground excited states, respectively. band origin exhibits a transient less than 100 ps, assigned to lifetime...
The calcination of (nano) Prussian blue analogues is now a fully controlled and understood route to synthesize Co–Fe spinel oxides.
We report a comprehensive study of the structures and deactivation processes protonated adrenaline through cryogenic UV photodissociation spectroscopy. Single double-resonance UV-UV hole burning spectroscopies have been performed compared to coupled-cluster SCS-CC2 calculations on ground first electronic states. Three conformers were assigned, two lowest energy gauche along with higher conformer an extended structure which is indeed global minimum in solution. This demonstrates kinetic...
Oxidation of the nucleobases is great concern for stability DNA strands and considered as a source mutagenesis cancer. However, precise spectroscopy data, in particular their electronic excited states are scarce if not missing. We here report an original way to produce isomer-selected radical cations bases, exemplified case cytosine, through photodissociation cold cytosine-silver (C-Ag+) complex. IR-UV dip C-Ag+ features fingerprint bands two keto-amino cytosine tautomers. UV (UVPD)...
We use UV and infrared photodissociation spectroscopy to study monohydrated protonated guanine in a dual cryogenic ion trap spectrometer. The complexes are formed through helium-mediated collisions between bare electrosprayed low-pressure water vapor clustering maintained at 180 K, before being transferred quadrupole 10 K. spectrum of the complex exhibits sharp vibronic transitions band origin becomes broader higher intensity further blue, which is very similar but with notable blue shift ∼1850 cm
The photophysics of biochromophore ions often depends on the isomeric or protomeric distribution, yet this and individual isomer contributions to an action spectrum, can be difficult quantify.
The Cover Feature illustrates the effect of a single water molecules upon photo physics cold protonated tryptophan. Vibrational spectra along with excited state dynamics are recorded by IR and UV cryogenic ion spectroscopy assigned comparison quantum chemistry calculations. More information can be found in Research Article Keisuke Hirata, Shun-Ichi Ishiuchi, Masaaki Fujii, Gilles Grégoire co-workers.
Ices are widely present in the cold regions across Universe, for instance, interstellar medium as mantles on and circumstellar dust surfaces of small bodies Solar System - beyond distance around 3-5 AU known “snowline" (i.e. at temperatures below 150-170 K). The continuous energetic processing icy objects induces physical chemical changes within ice. Laboratory experiments that simulate (ions, photons, electrons) ices therefore essential interpreting directing future astronomical...