A5040304923- Advanced Chemical Physics Studies
- Mass Spectrometry Techniques and Applications
- Atomic and Molecular Physics
- X-ray Spectroscopy and Fluorescence Analysis
- Photochemistry and Electron Transfer Studies
- Per- and polyfluoroalkyl substances research
- Atmospheric Ozone and Climate
- Toxic Organic Pollutants Impact
- Atmospheric chemistry and aerosols
- Analytical chemistry methods development
- Analytical Chemistry and Chromatography
- Spectroscopy and Quantum Chemical Studies
- Ion-surface interactions and analysis
- Metabolomics and Mass Spectrometry Studies
- Pesticide Residue Analysis and Safety
- Quantum optics and atomic interactions
- Catalytic Processes in Materials Science
- Effects and risks of endocrine disrupting chemicals
- Molecular Spectroscopy and Structure
- Nuclear Physics and Applications
- Graphite, nuclear technology, radiation studies
- History and advancements in chemistry
- Chemical Reactions and Mechanisms
- Spectroscopy and Laser Applications
- Photocathodes and Microchannel Plates
Agilent Technologies (United States)
2017-2025
Torrey Pines Institute For Molecular Studies
2025
University of Ottawa
2003-2010
Daresbury Laboratory
2006-2010
Cardiff University
2009-2010
Heriot-Watt University
1997-2010
Lomonosov Moscow State University
2010
Max Planck Society
1999-2005
Fritz Haber Institute of the Max Planck Society
1999-2004
Max Planck Institute for Plasma Physics
2000-2004
Collision cross section (CCS) measurements resulting from ion mobility–mass spectrometry (IM-MS) experiments provide a promising orthogonal dimension of structural information in MS-based analytical separations. As with any molecular identifier, interlaboratory standardization must precede broad range integration into workflows. In this study, we present reference drift tube mobility mass spectrometer (DTIM-MS) where improvements on the measurement accuracy experimental parameters...
Inner-shell photoelectron spectra of the N 1s level in N2 have been measured with sufficient resolution to resolve splitting between gerade and ungerade components. The selective enhancement component on σ shape resonance is clearly seen, confirming that resonant behavior mainly caused by σu channel. two components found be 97(3) meV.
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...
Valence and C1s core level photoelectron spectra of gaseous alanine have been recorded with synchrotron radiation. Using ab initio Green's Function calculations the vertical outer valence ionization energies CMS-Xα orbital cross-sections, it is possible to account well for features both new hν = 92 eV spectrum also its differences an earlier 21.2 spectrum. Good agreement may be achieved by considering just contribution a single molecular conformation. This agrees previous experimental...
The absolute photoabsorption, photoionization and photodissociation cross sections the quantum efficiency of ammonia deuterated have been measured from ionization threshold to 25 eV using a double ion chamber monochromated synchrotron radiation. photoabsorption spectrum displays extensive vibrational progressions associated with Rydberg series converging onto excited levels 2A2´´ state. New structure has observed for ND3 in 10.0-11.3 range, due transitions into , states recorded improved...
The absolute photoabsorption cross section of benzene (C6H6), encompassing the C 1s−1 π*e2u resonance, 1s threshold, satellite thresholds, and extending up to 800 eV, has been measured using synchrotron radiation. Measurements discrete absorption structure from below ionization threshold have performed at high resolution. In order unambiguously assign all present in section, photoelectron spectra were region 350 eV along with spectra. single-hole sections derived units, their angular...
Per- and polyfluoroalkyl substances (PFASs) are often present in complex mixtures at trace levels environmental samples, posing difficulties for analytical chemists. Ion mobility offers highly replicable identifiers, enabling the use of community-based libraries PFAS annotation nontargeted analysis. Currently, limited software exists to leverage capabilities liquid chromatography ion high-resolution mass spectrometry (LC-IM-HRMS) FluoroMatch IM is a free vendor-neutral open-source tool rapid...
Tandem mass spectrometry (MS/MS) is a powerful technique for structural identification of small molecules, yet significant portion MS/MS spectra from untargeted experiments remain unidentifiable through spectrum library matching. ModiFinder, computational tool, tackles this issue by predicting the site chemical modifications on known analogs unidentified compounds using data. However, ModiFinder's performance limited insufficient peak data and fragmentation annotation ambiguities. In study,...
Tetra-nitrogen (N(4)), which has been the subject of recent controversy [Cacace, d. Petris, and Troiani, Science 295, 480 (2002); Cacace, Chem. Eur. J. 8, 3839 Nguyen et al., Phys. A 107, 5452 (2003); Nguyen, Coord. Rev. 244, 93 (2003)] as well great theoretical interest, prepared from N(4) (+) cation then detected a reionized gaseous metastable molecule with lifetime exceeding 0.8 micros in experiments based on neutralization-reionization mass spectrometry. Moreover, we have used nature...
Abstract There are thousands of different per- and polyfluoroalkyl substances (PFAS) in everyday products the environment. Discerning abundance diversity PFAS is essential for understanding sources, fate, exposure routes, associated health impacts PFAS. While comprehensive detection requires use nontargeted mass spectrometry, data processing time intensive prone to error. automated approaches can compile all spectrometric evidence (e.g., retention time, isotopic pattern, fragmentation,...
Per- and polyfluoroalkyl substances (PFAS) are widespread, persistent environmental contaminants that have been linked to various health issues. Comprehensive PFAS analysis often relies on ultra-high-performance liquid chromatography coupled with high-resolution mass spectrometry (UHPLC HRMS) molecular fragmentation (MS/MS). However, the selection of ions for MS/MS using data-dependent results in only topmost abundant being selected. To overcome these limitations, All Ions (AIF) can be used...
The valence shell photoelectron spectrum, threshold and photoion coincidence (TPEPICO) mass spectra of acetone have been measured using synchrotron radiation. New vibrational progressions observed assigned in the X 2B2 state bands acetone-h6 acetone-d6, influence resonant autoionization on electron yield has investigated. dissociation thresholds for fragment ions up to 31 eV compared previous values. In addition, kinetic modeling region CH3* CH4 loss leads new values 78 +/- 2 kJ mol(-1) 75...
Per- and polyfluoroalkyl substances (PFAS) are widely used persistent synthetic chemicals that have been linked to adverse health effects. While the behavior of PFAS has evaluated in environment, our understanding reaction products mammalian systems is limited. This study identified biological transformation generated mass spectral libraries facilitate an automated search identification. The 27 PFAS, spanning 5 chemical subclasses (alcohols, sulfonamides, carboxylic acids, ethers, esters),...
The threshold photoelectron spectrum (TPES) of tetrahydrofuran (THF) is compared to that the unsaturated furan molecule. In general, there a similarity in orbital ionization profile for two species, though unlike furan, THF exhibits (modest) vibrational detail only (9b)(-1) X (2)B band. An adiabatic energy 9.445 +/- 0.010 eV has been derived from onset TPES spectrum. Threshold photoion coincidence spectroscopy was used explore loss hydrogen atom ionized over photon range 9.9-10.4 eV. RRKM...