Paramagnetic Resonance Absorption of Free Radicals

Size Modification of Nanographite System of Activated Carbon Fibers Studied by EPR

“…For self-organized systems confined in nanometer scale, nonlinear dielectric effect measurements for CCl 4 in ACF show divergence at transition, confirming the hexatic phase [3]. C 6 H 5 NO 2 molecules were chosen because of possible indication of the charge transfer from nanographite particles to guest molecules by electron hyperfine interaction with N or C nuclei [4]. Contact of water molecules with hydrophobic surfaces of nanographite particles of ACFs is characterized by physisorption process which can modify the host system [5].…”

Electron Paramagnetic Resonance in the Netherlands

“…It is written for arbitrary electron spin S and takes into account terms quadratic in S and I. Recently we added to our pulse spectrometer equipment for carrying out pulse experiments at C-band (4)(5)(6)(7)(8). This was used in investigations on disordered paramagnetic systems of biological importance (27).…”

“…The last few years have witnessed a rapid diffusion of this type of experiment in biology for the study of the ferrous ion (S=2) and metal clusters in proteins (73)(74)(75). More recently, Hagen's work has focused on EPR studies of "very high" half-integer spin systems (S=7/2, 9/2) resulting from exchange coupling in larger iron-sulphur clusters (6)(7)(8) in complex redox enzymes, e.g. nitrogenase (76,77).…”

“…The physicists concentrated mainly on paramagnetic inorganic salts, paramagnetic transition elements in crystals, impurity centers in semiconductors and luminescent centers. The interest of chemists was more directed to larger paramagnetic systems, especially after the publication of Weissman and his colleagues in 1953 of electron paramagnetic resonance spectra of large paramagnetic organic molecules exhibiting a rich hyperfine structure (7).…”

In situ analysis of free radicals from the photodecomposition of hydrogen peroxide using a frequency-mixing magnetic detector

“…Generally, free radicals have an open-shell configuration with unpaired electrons, making them paramagnetic species. 2 Previously, considerable effort was made to investigate the generation, degradation, and kinetics of free radicals using analytical methods such as titration, colorimetry, fluorescence, and biochemical methods using peroxides. [3][4][5][6][7] However, these methods suffer from the contamination of the samples caused by the probe chemicals or enzymes.…”