A5027301068- Laser-Matter Interactions and Applications
- Mass Spectrometry Techniques and Applications
- Advanced Chemical Physics Studies
- Spectroscopy and Quantum Chemical Studies
- Ion-surface interactions and analysis
- Astrophysics and Star Formation Studies
- Photoreceptor and optogenetics research
- Hydraulic and Pneumatic Systems
- Electron and X-Ray Spectroscopy Techniques
- DNA and Nucleic Acid Chemistry
- Molecular spectroscopy and chirality
- Atomic and Molecular Physics
- Cold Atom Physics and Bose-Einstein Condensates
- Photorefractive and Nonlinear Optics
- Photocathodes and Microchannel Plates
- Diamond and Carbon-based Materials Research
- Molecular Spectroscopy and Structure
- Geochemistry and Geologic Mapping
- Advanced biosensing and bioanalysis techniques
- Cavitation Phenomena in Pumps
- Quantum, superfluid, helium dynamics
- Quantum Electrodynamics and Casimir Effect
- Advanced Fiber Laser Technologies
- Water Systems and Optimization
- Strong Light-Matter Interactions
Kyoto University
2023-2024
Institut Lumière Matière
2021-2024
Centre National de la Recherche Scientifique
2021-2024
Université Claude Bernard Lyon 1
2016-2024
Photoionization of acetylene by extreme ultraviolet light results in a stand-alone contribution from the outermost valence orbital, followed well-separated photoelectron bands deeper molecular orbitals. This makes an ideal candidate for probing photoionization dynamics polyatomic molecules free spectral congestion often arising after interaction with attosecond pulse train. Here, using angle-resolved interferometric technique, we extract time delays orbital relative to atomic target, namely...
We report ultrafast extreme ultraviolet photoelectron spectroscopy of 6-methyluracil (6mUra) and 5-fluorouracil (5FUra) in the gas phase 6mUra 5-fluorouridine an aqueous environment. In phase, internal conversion (IC) occurs from 1ππ* to 1nπ* states tens femtoseconds, followed by intersystem crossing 3ππ* state several picoseconds. solution, undergoes IC almost exclusively ground (S0) about 100 fs, which is essentially same process as that for unsubstituted uracil, but much faster than...
Ultrafast internal conversion of furan upon deep UV excitation at 200 nm is studied by using extreme ultraviolet time-resolved photoelectron spectroscopy with a time resolution 15 fs. Ballistic nuclear wavepacket motion from the 1B2(ππ*) state to ground fully observed 21.7 eV probe pulses. Through performance comparison results electronic structure calculations MS(3)-CASPT2(10,10)/cc-pVTZ level theory, signals conical intersection regions are identified.
The effect of deuterium isotopes on the internal conversion ethylene is studied by using extreme ultraviolet time-resolved photoelectron spectroscopy. For deuterium-labeled ethylene, time scale for ultrafast increased a factor approximately √2, in agreement with results ab initio multiple spawning calculations, indicating essential role played hydrogen motion process. Following conversion, metastable species an electron binding energy ∼9 eV produced, and it decays constant similar to that...
An investigation of how polycyclic aromatic hydrocarbons respond to extreme ultraviolet radiation provides insight into internal molecular dynamics that can help improve models interstellar chemistry.
Following ionization by an extreme ultraviolet (XUV) attosecond pulse train, a polyatomic molecule can be promoted to more-than-one excited states of the residual ion. The ensuing relaxation dynamics is often facilitated several reaction coordinates, making them difficult disentangle usual spectroscopic means. Here, we show that in atto-chemistry isotope labeling efficient tool for unraveling pathways highly photoionized molecules. Employing XUV pump and near-infrared probe pulse, found...
Unraveling ultrafast processes induced by energetic radiation is compulsory to understand the evolution of molecules under extreme excitation conditions. To describe these photo-induced processes, one needs perform time-resolved experiments follow in real time dynamics absorption light. Recent have demonstrated that on few tens femtoseconds are expected such situations and a very challenging task identify role played electronic nuclear degrees freedom, charge, energy flows structural...
Abstract We present experiments where extreme ultraviolet femtosecond light pulses are used to photoexcite large molecular ions at high internal energy. This is done by combining an electrospray ionization source and a mass spectrometer with pulsed based on harmonic generation. allows one study the interaction between energy photons selected in conditions that accessible large-scale facilities. show even without ion trapping device, systems as protein can be studied. observe induced...
Ultrafast charge, energy and structural dynamics in molecules are driven by the topology of multidimensional potential surfaces that determines coordinated electronic nuclear motion. These processes also strongly influenced interaction with molecular environment, making very challenging a general understanding these on microscopic level. Here we use electrospray mass spectrometry technologies to produce isolated ions controlled micro-environment. We measure ultrafast photo-induced ππ*-πσ*...
The effects of methyl substitution on the ultrafast internal conversion from S
Gas phase experiments combined with ultrafast technologies can provide information on the intrinsic properties of molecular systems at picosecond, femtosecond, or even attosecond timescales. However, these are often limited to relatively simple model systems. In this context, electrospray ionization sources (ESI) have offered new perspectives as they allow produce large fragile ions in gas phase, mimicking molecules their natural environment. While time-resolved UV-visible been successfully...
Transmission matrix and hydroacoustic sources of a centrifugal pump, at very low load, are determined by an experimental method ; with external excitation (f1ow fluctuations generated small rotating valve connected on by-pass around the machine), more important than pump (even load), transmission is accurately determined. Then obtained simple difference. The main results : - in terms no variation matrix, about sources, under particular load (beginning recirculation phenomena), spectra...
Photoionization as a half-scattering process is not instantaneous. Usually, time delays in photoionization are of the order few tens attoseconds (1 = 10$^{-18}$ s). While going from single atom to nano-object, one can expect delay increase since photoelectron scatters over larger distance. Here, we show that this no longer valid case planar systems. Using attosecond interferometry, find 2D carbon-based molecule, naphthalene, significantly smaller compared its 3D diamond-like counterpart,...
We present a new experimental set-up combining ultrafast XUV technics with electrospray sources. First results of dynamics in large molecular ions are shown demonstrating perspectives for applications attochemistry.
The development of attosecond technology has brought new perspectives in real time observation electron and nuclear dynamics atoms molecules, with the ultimate goal controlling reactivity molecules down to resolution [1] . In this context, understanding processes occurring after absorption high energy photons complex is compulsory. Recently, experiments conducted on large systems [2] , [3] have shown remarkable results photo-induced such as charge migration