Optical and EPR Spectroscopy of Manganese Ions in Fluorozirconate Glasses

The first step of electrochemical oxidation of 2-phenyl- and 2-(4-tolyl)-1,3,4,7-tetramethylisoindoles in anhydrous acetonitrile produces relatively stable cationradicals which have been studied by means of EPR spectroscopy using the method of internal electrochemical generation of radicals under reduced temperature. The same electrochemical behaviour of the both studied derivatives and identical EPR spectra of their cationradicals can be explained within the Huckel MO method. The largest contribution to the magnitude of splitting constant of nitrogen nucleus is due to π-σ-spin polarization of C-N bonds caused by high spin abundance of pz-AO of carbon atoms. Half-life of decomposition of the studied cationradicals is 4 min at -30°C.

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Photoassisted Production of O2-• and H2 in Aqueous Medium Stimulated by Polythiophene in ZSM-5 Zeolite Channels

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19990149 ◽

1999 ◽

Vol 64 (1) ◽

pp. 149-156 ◽

Cited By ~ 7

Author(s):

Gabriel Čík ◽

František Šeršeň ◽

Alena Bumbálová

Keyword(s):

Reactive Oxygen Species ◽

Ion Exchange ◽

Visible Light ◽

Aqueous Medium ◽

Exchange Reaction ◽

Epr Spectroscopy ◽

Reactive Oxygen ◽

Oxygen Species ◽

Water Reduction ◽

Ion Exchange Reaction

The formation of reactive oxygen species due to irradiation by a visible light of the polythiophene deposited in ZSM-5 zeolite channels in aqueous medium has been studied. Polymerization of thiophene was carried out in zeolite channels after the ion-exchange reaction of Na+ for Fe3+. By means of EPR spectroscopy, the temporarily generated 1O2 in irradiated aqueous medium was proved. The formation of O2-• was confirmed by the reduction of Fe3+-cytochrome c. Irradiation led to the water reduction to hydrogen.

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Monitoring of the Mechanism of Mn Ions Incorporation into Quantum Dots by Optical and EPR Spectroscopy

Photonics ◽

10.3390/photonics6040107 ◽

2019 ◽

Vol 6 (4) ◽

pp. 107

Author(s):

Yuriy G. Galyametdinov ◽

Dmitriy O. Sagdeev ◽

Andrey A. Sukhanov ◽

Violeta K. Voronkova ◽

Radik R. Shamilov

Keyword(s):

Electron Paramagnetic Resonance ◽

Magnetic Properties ◽

Luminescent Properties ◽

Manganese Concentration ◽

Manganese Ions ◽

Paramagnetic Resonance ◽

Synthesis Of Nanoparticles ◽

Zinc Sulfide Nanoparticles ◽

Optical And Magnetic Properties ◽

Electron Paramagnetic

Synthesis of nanoparticles doped with various ions can significantly expand their functionality. The conditions of synthesis exert significant influence on the distribution nature of doped ions and therefore the physicochemical properties of nanoparticles. In this paper, a correlation between the conditions of synthesis of manganese-containing cadmium sulfide or zinc sulfide nanoparticles and their optical and magnetic properties is analyzed. Electron paramagnetic resonance was used to study the distribution of manganese ions in nanoparticles and the intensity of interaction between them depending on the conditions of synthesis of nanoparticles, the concentration of manganese, and the type of initial semiconductor. The increase of manganese concentration is shown to result in the formation of smaller CdS-based nanoparticles. Luminescent properties of nanoparticles were studied. The 580 nm peak, which is typical for manganese ions, becomes more distinguished with the increase of their concentration and the time of synthesis.

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