Search results for " SPECTROSCOPY"
showing 10 items of 6851 documents
Effect of Gold(I) on the Room-Temperature Phosphorescence of Ethynylphenanthrene.
2020
The synthesis of two series of gold(I) complexes containing the general formulae PR 3 ‐Au‐C≡C‐phenanthrene (PR 3 = PPh 3 ( 1a / 2a ), PMe 3 ( 1b / 2b ), PNaph 3 ( 1c / 2c )) or (diphos)(Au‐C≡C‐phenanthrene) 2 (diphos = 1,1‐ bis (diphenylphosphino)methane, dppm ( 1d / 2d ); 1,4‐ bis (diphenylphosphino)butane, dppb ( 1e / 2e )) have been synthesized. The two series differ on the position of the alkynyl substituent on the phenanthrene chromophore, being at the 9‐position (9‐ethynylphenanthrene) for the L1 ‐series and at the 2‐position (2‐ethynylphenanthrene) for the L2 ‐series. The compounds have been fully characterized by 1 H and 31 P NMR and IR spectroscopy, mass spectrometry and single cry…
Surfactant-Mediated Morphology and Photocatalytic Activity of α‑Ag2WO4 Material
2018
In the present work, the morphology (hexagonal rod-like vs cuboid-like) of an α-Ag2WO4 solid-state material is manipulated by a simple controlled-precipitation method, with and without the presence of the anionic surfactant sodium dodecyl sulfate (SDS), respectively, over short reaction times. Characterization techniques, such as X-ray diffraction analysis, Rietveld refinement analysis, Fourier-transform (FT) infrared spectroscopy, FT Raman spectroscopy, UV–vis spectroscopy, transmission electron microscopy (TEM), high-resolution TEM, selected area electron diffraction, energy-dispersive X-ray spectroscopy, field emission-scanning electron microscopy (FE-SEM), and photoluminescence emission…
Conformational-Dependent Photodissociation of Glycolic Acid in an Argon Matrix
2023
Ultraviolet-induced photodissociation and photo-isomerization of the three most stable conformers (SSC, GAC, and AAT) of glycolic acid are investigated in a low-temperature solid argon matrix using FTIR spectroscopy and employing laser radiation with wavelengths of 212 nm, 226 nm, and 230 nm. The present work broadens the wavelength range of photochemical studies of glycolic acid, thus extending the understanding of the overall photochemistry of the compound. The proposed kinetic model for the photodissociation of glycolic acid proceeds from the lowest energy conformer (SSC). The model suggests that ultraviolet light induces isomerization only between the SSC and GAC conformers and between …
Hard x-ray photoelectron spectroscopy: a snapshot of the state-of-the-art in 2020
2021
Journal of physics / Condensed matter 33(23), 233001 (1-44) (2021). doi:10.1088/1361-648X/abeacd
Time-resolved core-level photoemission data of tungsten diselenide
2020
Pump-probe core-level photoemission spectroscopy data of tungsten diselenide (WSe2) measured using an electron momentum microscope at the FLASH Free-electron laser.
Applications of Quantum Chemistry in Spectroscopy: Molecules, Complexes of Van der Waals, trapped Molecules
2009
I described in this memory my activities as a researcher at Tomsk well before 2003, in succession to the State University of Tomsk in the Faculty of Physics, Institute of Physics of Siberia, and the Institute of 'Atmospheric Optics, in France since then, mostly at the University of Bourgogne (ICB), but also at the University of Lille I (PhLAM) and the University of Marne-la-Vallée (LCT). Part of my work has been dedicated to the evaluation by calculating ab initio of rovibrational constants for quasi-spherical molecules. The centrifugal distortion constants and the dipole moment of the molecule SO2F2 were calculated to validate the tensor theory and interpreter the spectrum. I twas shown th…
Terahertz Absorption change in Photosynthetic Reaction Center upon photoactivation
2012
Photosynthetic reaction center is a membrane protein which plays an important role in converting solar energy into chemical energy. Upon continuous illumination a charge separation occurs within the protein which is stable for several seconds [1]. The stability of this state is very important to protect the protein against the release of excess heat and an instable radical due to charge recombination. Absorption of terahertz radiation corresponds to the excitation of large vibrations in the protein and is thus suitable for studying its different dynamical states. Here we recorded terahertz absorption spectra of the dark and illuminated state of reaction centre from the purple membrane bacte…
Photoinduced changes in phytochromes studied by means of low temperature UV-Vis spectroscopy
2018
Phytochromes are a major family of red-light-sensing kinases that control diverse cellular functions in plants, bacteria and fungi. These proteins must relay structural signals from the sensory site over large distances to regulatory output domains. To accomplish this function, they undergo rather large structural changes from one state to another. The general aim of this work was to study these structural changes and possible protonation states of the photosensory core of the bacteriophytochrome from Deinococcus radiodurans in the intermediate states of the photoreaction, which became possible to observe under low temperatures. Moreover, it was interesting to investigate the role Serine272…
Biocompatibility and Antibacterial Properties of ZnO-Incorporated Anodic Oxide Coatings on TiZrNb Alloy
2020
In a present paper, we demonstrate novel approach to form ceramic coatings with incorporated ZnO nanoparticles (NPs) on low modulus TiZrNb alloy with enhanced biocompatibility and antibacterial parameters. Plasma Electrolytic Oxidation (PEO) was used to integrate ZnO nanoparticles (average size 12&ndash
Aluminum tri-isopropoxide as an alternative precursor for atomic layer deposition of aluminum oxide thin films
2019
Due to the safety challenges associated with the use of trimethylaluminum as a metal precursor for the deposition of alumina, different chemicals have been investigated over the years to replace it. The authors have investigated the use of aluminum tri-isopropoxide (TIPA) as an alternative alkoxide precursor for the safe and cost-effective deposition of alumina. In this work, TIPA is used as a stable Al source for atomic layer deposition (ALD) of Al2O3 when different oxidizing agents including water, oxygen plasma, water plasma, and ozone are employed. The authors have explored the deposition of Al2O3 using TIPA in ALD systems operating in vacuum and atmospheric pressure conditions. For the…