Electron paramagnetic resonance parameters

Gewirth AA, Cohen SL, Schugar HJ, Solomon El. 1987. Spectroscopic and theoretical studies of the unusual electron paramagnetic resonance parameters of distorted tetrahedral cupric sites correlations to x-ray spectral features of core levels. Inorg Chem 26 1133-1146. 

Electron paramagnetic resonance (EPR) spectroscopy is yet another diagnostic tool for the detection of isomorphous substitution of Ti. Its sensitivity is very high, and investigations can be performed with samples even with very low contents of paramagnetic species. The spectra and g parameters are sensitive to the local structure and associated molecular distortions. Hence, it is an ideal tool to characterize Ti in titanosilicates. Ti in the + 4 oxidation state in titanosilicates is diamagnetic and hence EPR-silent. Upon contacting with CO or H2 at elevated... 

Stable organophosphorus Jt-radicals were observed for some derivatives of l,3-diphosphetane-2,4-diyls 6. A reversible electrochemical or chemical oxidation of 6c-e leads to electron paramagnetic resonance (EPR)-active radicals, whose spectroscopic parameters were elucidated (Figure 1) <1996TH1, 1998TH1>. 

Crossover Temperature for Various Glass Formers as Reported by the Different Methods From the Temperature Dependence of the Stretching Parameter y(T), Scaling the Time Constant xa — xa(r) [cf. Eq. (42)], Non-ergodicity Parameter 1 —f(T) Obtained from Spectra Analysis, Electron Paramagnetic Resonance (EPR), and from Tests of the Asymptotic Laws of Mode Coupling Theory ... 

Neese, E. (2007) Quantum Chemical Approaches to Spin Hamiltonian Parameters, in Electron Paramagnetic Resonance (eds B.C. Gilbert, M.J. Davies and D.M. Murphy), Royal Society of Chemistry, Cambridge, 20, p. 73. 

Prom the electron paramagnetic resonance (EPR) spectmm of the nitroxide side chain, four primary parameters are obtained 1) solvent accessibility, 2) mobility of the R1 side chain, 3) a polarity index for its immediate environment, and 4) the distance between R1 and another paramagnetic center in the protein. Solvent accessibility of the side chain is determined from the collision frequency of the nitroxide with paramagnetic reagents in solution. The mobility, polarity, and distances are deduced from the EPR spectral line shape. For regular secondary stmc-tures, accessibility, mobility, and polarity are periodic functions of sequence position. The period and the phase of the function reveal the type of secondary stmcture and its orientation within the protein, respectively (71, 74). In the case of membrane proteins, the topography of the secondary stmcture with respect to the membrane surface can also be described (75, 76). 

Electron paramagnetic resonance (EPR) is a powerful tool for studying radicals such as NO. This method specifically detects molecules with unpaired electrons. The g-value, a dimensionless parameter determined from an EPR spectram, is influenced by the spin and orbital angular momentum of the unpaired... 

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