A5038206478- Advanced Chemical Physics Studies
- Mass Spectrometry Techniques and Applications
- Electron and X-Ray Spectroscopy Techniques
- Advancements in Solid Oxide Fuel Cells
- X-ray Spectroscopy and Fluorescence Analysis
- Electronic and Structural Properties of Oxides
- Atomic and Molecular Physics
- Magnetic and transport properties of perovskites and related materials
- DNA and Nucleic Acid Chemistry
- Ion-surface interactions and analysis
- Laser-Matter Interactions and Applications
- Inorganic Fluorides and Related Compounds
- Fuel Cells and Related Materials
- Electrocatalysts for Energy Conversion
- Advanced Electron Microscopy Techniques and Applications
- Spectroscopy and Quantum Chemical Studies
- Luminescence Properties of Advanced Materials
- Photochemistry and Electron Transfer Studies
- Advanced X-ray Imaging Techniques
- Semiconductor materials and devices
- nanoparticles nucleation surface interactions
- Copper-based nanomaterials and applications
- X-ray Diffraction in Crystallography
- Surface and Thin Film Phenomena
- Catalytic Processes in Materials Science
University of Tartu
2014-2024
University of Turku
2013-2023
Czech Academy of Sciences, Institute of Physics
2010-2023
Tohoku University
2019
Synchrotron soleil
2019
Turku Centre for Biotechnology
2018
A detailed experimental and theoretical investigation of the dynamics leading to fragmentation doubly ionized molecular thiophene is presented. Dissociation double-ionized molecules was induced by S $2p$ core photoionization ionic fragments were detected in coincidence with Auger electrons from core-hole decay. Rich observed electron-ion-ion maps exhibiting ring breaks accompanied hydrogen losses and/or migration. The probabilities various dissociation channels seen be very sensitive...
We report unambiguous experimental and theoretical evidence of intramolecular photoelectron diffraction in the collective vibrational excitation that accompanies high-energy photoionization gas-phase CF4, BF3, CH4 from 1s orbital central atom. show ratios between vibrationally resolved cross sections (v-ratios) exhibit pronounced oscillations as a function photon energy, which is fingerprint electron by surrounding atomic centers. This interpretation supported excellent agreement...
We report an experimental and theoretical study of single-molecule inner-shell photoemission measured over extended range photon energies. The vibrational intensity ratios $I(\ensuremath{\nu}=1)/I(\ensuremath{\nu}=0)$ from the C $1s$ photoelectron spectra carbon monoxide, although mostly determined by bond length change upon ionization, are shown to be affected also recoil scattering neighboring oxygen atom. Static-exchange density functional theory (DFT) is used encompass all these effects...
Since spring 2019 an experimental setup consisting of electron spectrometer and ion time-of-flight mass for diluted samples has been available users at the FinEstBeAMS beamline MAX IV Laboratory in Lund, Sweden. The enables to study interaction atoms, molecules, (molecular) microclusters nanoparticles with short-wavelength (vacuum ultraviolet X-ray) synchrotron radiation follow nuclear dynamics induced by this interaction. Test measurements N2 thiophene (C4H4S) molecules have demonstrated...
The Coulomb explosion mechanism of a CH<sub>2</sub>I<sub>2</sub> molecule is rather different to that CH<sub>3</sub>I. kinetic energy iodine ions ∼3 times larger due repulsion the two ions, while carbon almost same for both, as indicated by red arrows represent energies atomic ions.
Photofragmentation of thymine and 5-bromouracil into cation neutral fragments following the core ionization by soft x-rays using photoelectron-photoion-photoion coincidence technique has been studied. The fragment ion mass spectra were recorded in with C 1s photoelectron spectra. In case thymine, deuterated samples used to identify fragments. Deuteration or bromination allowed us study not only main fragmentation channels these pyrimidine bases, but also investigate if replacement an...
X-ray free-electron lasers (XFELs) made available a new regime of x-ray intensities, revolutionizing the ultrafast structure determination and laying foundations novel field nonlinear optics. Although earlier studies revealed nanoplasma formation when an XFEL pulse interacts with any nanometer-scale matter, process itself has never been decrypted its timescale was unknown. Here we show that time-resolved ion yield measurements combined near-infrared laser probe reveal surprisingly population...
Abstract The increasing availability of X-ray free-electron lasers (XFELs) has catalyzed the development single-object structural determination and dynamics tracking in real-time. Disentangling molecular-level reactions triggered by interaction with an XFEL pulse is a fundamental step towards developing such applications. Here we report real-time observations XFEL-induced electronic decay via short-lived transient states diiodomethane molecule, using femtosecond near-infrared probe laser. We...
The dependence of the fragmentation doubly charged gas-phase methionine (C5H11NO2S) on electronic-state character parent ion is studied experimentally by energy-resolved electron ion–ion coincidence spectroscopy. dication electronic states are populated Auger transitions following site-specific sulfur 2p core ionization. Two channels observed to be strongly dependent with vacancies in weakly bound molecular orbitals. All-electron calculations applied assign final ionized methionine. In...
We have studied the fragmentation of gas phase thymidine following valence and core ionization using synchrotron radiation, combined with electron energy ion mass resolved detection in coincidence. To identify certain fragment masses 13C labelled was also used. find that large part, photofragmentation can be described as separated thymine 2-deoxy-d-ribose cations. However, intact radical cation, formation base sugar cations from glycosidic bond cleavage several new thymidine-specific...
X-ray absorption commonly involves dissociative core ionization producing not only momentum correlated charged fragments but also low- and high-energy electrons capable of inducing damage in living tissue. This gives a natural motivation for studying the induced fragmentation processes biologically important molecules such as amino acids. Here acid glycine following carbon 1s has been studied. Using photoelectron-photoion-photoion coincidence technique, detailed analysis on sample molecule...
Fragmentation of gas-phase chloro- and bromoacetic acid samples, particularly its dependency on the atomic site initial core ionization, was studied in photoelectron-photoion-photoion coincidence (PEPIPICO) measurements. The fragmentation investigated after ionizing carbon $1s$ bromine $3d$ or chlorine $2p$ orbitals. It observed that samples had many similar pathways their relative weights depended strongly ionization site. Additional Auger PEPIPICO measurements revealed a clear dependence...
The electronic structure and photofragmentation in outer inner valence regions of Sen (n ⩽ 8) clusters produced by direct vacuum evaporation have been studied with size-selective photoelectron-photoion coincidence technique using vacuum-ultraviolet synchrotron radiation. experimental ionization potentials these were extracted from the partial ion yield measurements. calculations for possible geometrical structures microclusters executed. energies calculated compared results. In addition,...
Abstract Single-photon laser enabled Auger decay (spLEAD) is an electronic de-excitation process which was recently predicted and observed in Ne. We have investigated it using bichromatic phase-locked free electron radiation extensive angle-resolved photoelectron measurements, supported by a detailed theoretical model. first used separately the fundamental wavelength resonant with Ne + 2 s –2 p transition, 46.17 nm, its second harmonic, 23.08 then their combination. In latter case phase...
The persistent photoinduced magnetization (PPM) in the low bandwidth material Pr(1-x)Ca(x)MnO₃ at hole doping level of x = 0.1 is reported. Upon zero-field cooling under photoexcitation, significant improvement ferromagnetic (FM) ordering was observed temperature spin-glass phase. However, upon field cooling, FM found to be suppressed due weakening double-exchange interaction. High kinetic energy x-ray photoelectron spectroscopy measurements indicated a slight increase Mn³⁺ peak...