A5013134479- Electron Spin Resonance Studies
- Lanthanide and Transition Metal Complexes
- Magnetism in coordination complexes
- Advanced NMR Techniques and Applications
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Solid-state spectroscopy and crystallography
- Radioactive element chemistry and processing
- Gas Sensing Nanomaterials and Sensors
- Metalloenzymes and iron-sulfur proteins
- 2D Materials and Applications
- Photochemistry and Electron Transfer Studies
- Ionic liquids properties and applications
- Advanced Photocatalysis Techniques
- Electrocatalysts for Energy Conversion
- Analytical chemistry methods development
- Extraction and Separation Processes
- Photosynthetic Processes and Mechanisms
- RNA modifications and cancer
- MXene and MAX Phase Materials
- ZnO doping and properties
- Ammonia Synthesis and Nitrogen Reduction
- NMR spectroscopy and applications
- Transition Metal Oxide Nanomaterials
- Advanced battery technologies research
National Institute of Technology Goa
2020-2024
Centre National de la Recherche Scientifique
2012-2017
CEA Grenoble
2012-2017
Laboratoire de Chimie et Biologie des Métaux
2012-2017
Commissariat à l'Énergie Atomique et aux Énergies Alternatives
2012-2017
Université Grenoble Alpes
2012-2017
Institut Nanosciences et Cryogénie
2012-2016
University of Denver
2007-2014
Institut de Recherches en Technologies et Sciences pour le Vivant
2012
Université Joseph Fourier
2012
The validity of the popular point−dipole approximation for interpretation zero-field splitting (ZFS) parameter (D-value) in EPR spectroscopy is studied. This central importance determination distances by analysis data. In this work, a detailed experimental (EPR and X-ray crystallography) theoretical study model system (2,2′,5,5′-tetra(tert-butyl)-4,4′-bis(ethoxy-carbonyl)-3,3′-bipyrrolyl-1,1′-dioxyl) was performed to understand scope limitations spectroscopy. For diradical, radical−radical...
Electron spin lattice relaxation rates were measured for 12 nitroxyls with molecular weights between 144 and 438, galvinoxyl, 1,3-bisdiphenylene-2-phenylallyl (BDPA), 2,2-diphenyl-1-picrylhydrazyl (DPPH) in glassy sucrose octaacetate. Relaxation polar also sorbitol. Dependence on T where V eff is effective volume γ a material-specific parameter, was used to compare processes. Values of determined based libration octaacetate (γ = 3.5), tumbling viscous decalin at 233 K 4.7), or heavy mineral...
To determine the impact of electron−electron spin−spin interactions on electron spin relaxation rates, 1/T1 and 1/Tm were measured for nitroxide monoradical, diradical, tetraradical derivatives 1,3-alternate calix[4]arenes, two pegylated high-spin diradicals, an azine-linked diradical. The synthesis characterization by SQUID (superconducting quantum interference device) magnetometry one in which nitroxides are conformationally constrained to be coplanar with m-phenylene unit, is reported....
Abstract Site‐directed spin labeling and EPR spectroscopy offer accurate, sensitive tools for the characterization of structure function macromolecules their assemblies. A new rigid label, spirocyclohexyl nitroxide α‐amino acid its N ‐(9‐fluorenylmethoxycarbonyl) derivative, have been synthesized, which exhibit slow enough spin‐echo dephasing to permit accurate distance measurements by pulsed at temperatures up 125 K in 1:1 water/glycerol higher matrices with glass transition temperatures....
Between 65 and 175 K, nitroxyl radicals with spirocyclohexyl groups at the 2- 6-positions of piperidine ring exhibit spin echo dephasing rates that are slower than for 2,5-gem-dimethyl or 2,6-gem-dimethyl substituents currently used as labels, slow enough to permit DEER measurements temperatures up about 125 K labels analogous structures.
1,3-Alternate calix[4]arene with para-phenylene spacers connecting nitroxide monoradicals and high-spin (S = 1) diradicals provides tetraradical octaradical scaffolds that possess conformations slow electron spin relaxation rates (1/T1). Such may facilitate tuning of are more favorable for MRI or DNP applications.
The human mitochondrial electron transfer flavoprotein (ETF) accepts electrons from at least 10 different dehydrogenases and transfers to a single acceptor in the inner membrane. Paracoccus denitrificans ETF has identical function, shares same three-dimensional structure functional domains, exhibits conformational mobility. It been proposed that mobility of αII domain permits promiscuous behavior with respect variety redox partners. Double electron−electron resonance (DEER) measurements...
Human electron transfer flavoprotein (ETF) is a soluble mitochondrial heterodimeric that links fatty acid β-oxidation to the main respiratory chain. The crystal structure of human ETF bound medium chain acyl-CoA dehydrogenase indicates flavin adenine dinucleotide (FAD) domain (αII) mobile, which permits more rapid with donors and acceptors by providing closer access allows accept electrons from at least 10 different dehydrogenases. Sequence homology high low-angle X-ray scattering identical...
Novel amide ligands in the ionic liquid (1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide) were utilized for liquid-liquid biphasic mass transfer of Eu3+ ions from aqueous acidic waste solution. The cation exchange mechanism was found to be operative with formation [Eu(NO3)2L3]+ species (L = 4-chloro-N-(1-methyl-1H-pyrazol-3-yl)picolinamide). However, presence an inner-sphere water molecule revealed by density functional theory (DFT) calculations. viscosity-induced slower...
TYW1 is a metalloenzyme involved in the modifications of guanosine 37 Phe-tRNA Eukaryota and Archaea. It catalyzes second step Wybutosine biosynthesis, which consists formation tricyclic compound imG-14 from m1G using pyruvate SAM (S-adenosyl-methionine) as co-substrates. Two [4Fe-4S] clusters are needed catalytic process. One effects reductive binding SAM, initiates radical reaction that inserts C-C moiety into m1G. The other cluster binds molecule provides motif. Using combination EPR...