Optical and electron paramagnetic

Optical and Electron Paramagnetic Resonance Spectroscopy of Actinide Ions in Single Crystals... 

Photoinduced electron transfer in dyad 17 and related compoimds has been extensively studied using optical and electron paramagnetic resonance (EPR) tech-... 

Yonetani, T., Yamamoto, FI., Erman, J. E., Leigh, J. S., Jr., and Reed, G. H. (1972). Electromagnetic properties of hemoproteins. V. Optical and electron paramagnetic resonance characteristics of nitric oxide derivatives of metalloporphyrin-apohemoprotein complexes. J. Biol. Chem. 247, 2447-2455. 

Vanin AF, Malenkova IV, Serezhenkov VA (1997) Iron catalyzes both decomposition and synthesis of S-nitrosothiols optical and electron paramagnetic resonance studies. Nitric Oxide 1 191-203... 

Amine-terminated, full-generation PAMAM and PPI dendrimers, as well as carboxylate-terminated half-generation PAMAM dendrimers, can directly bind metal ions to their surfaces via coordination to the amine or acid functionality. A partial hst of metal ions that have been bound to these dendrimers in this way includes Na+, K+, Cs+, Rb+, Fe +, Fe +, Gd +, Cu+, Cu +, Ag+, Mn +, Pd, Zn, Co, Rh+,Ru +,andPt + [18,19,27,36,54,82-96]. Tuxro et al.have also shown that the metal ion complexes, such as tris(2,2 -bipyridine)ruthenium (Rulbpylj), can be attached to PAMAM dendrimer surfaces by electrostatic attraction [97]. A wide variety of other famihes of dendrimers have also been prepared that bind metal ions to their periphery. These have recently been reviewed [3]. Such surface-bound metal ions can be used to probe dendrimer structure using optical spectroscopy, mass spectrometry, and electron paramagnetic resonance (EPR) [86-88,90,97-99]. 

It is doubtful that a distinction can be made between the various charge distributions proposed by purely chemical means, although this might be possible in principle. We thus rely on physical methods such as optical studies, x-ray analysis, polarography, magnetic susceptibility, and electron paramagnetic resonance (EPR) studies for a determination of the stmcture of these complex cations. This is not to say that the chemistry of these compounds is no longer of... 

Two papers have been presented on the photochemistry of 5-methylphena-zinium salts in aqueous solution. Fluorescence, optical flash photolysis, and electron paramagnetic resonance (e.p.r.) techniques have been used to elucidate various aspects of product formation and quantum yield. Two products have been identified, namely the 5-methyl-10-hydrophenazinium cation radical (MPH ) and the pyocyanine (l-hydroxy-5-methyl-phenozinium) cation (PyH ) in a stoicheiometric ratio of 2 1. The quantum yield of formation of (MPH ) was found to be 0.29 0.03 at pH 7.0 and 1.1 0.1 at pH 3.0. The triplet state of MP (Ti) has also been detected by triplet-triplet absorption and is found to have a lifetime of 0.5 ns. Flash photolysis and e.p.r. have also been used to study a geminate triplet radical pair obtained from hydrogen abstraction by excited triplet acetone from propan-2-ol. The authors demonstrate that the geminate pairs contribute most of the polarization in photochemically-induced dynamic electron polarization (CIDEP) as compared with free random-phase pairs. 

Bogomolova, L.D., Jachkin, V.A., Lazukin, V.N., Pavlushkina, T.K., and Shmuckler, V.A. 1978. The electron paramagnetic resonance and optical spectra of copper and vanadium in phosphate glasses. Journal of Non-Crystalline Solids 28 375-389. 

Figure 1.1 The electiomagnetic spectrum, showing the different microscopic excitation sources and the spectroscopies related to the different spectral regions. XRF, X-Ray Fluorescence AEFS, Absorption Edge Fine Structure EXAFS, Extended X-ray Absorption Fine Structure NMR, Nuclear Magnetic Resonance EPR, Electron Paramagnetic Resonance. The shaded region indicates the optical range.

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