Electron spin resonance data

Goslar, J., L. Piekara-Sady et al. (1994). ENDOR data tabulations. In Poole, C. P. and Farach, H. A. (eds.), Handbook of Electron Spin Resonance Data Sources, Computer Technology, Relaxation and ENDOR. New York AIP Press. 

Electron Spin Resonance Data for Hyperfine Interaction... 

Electron spin resonance data for a representative selection of organic nitroxides 1- ... 

Selected electron spin resonance data for spin adducts of C-nitroso-compounds (see also Table l)0 ... 

There are approximately 2000 papers per year published that contain electron spin resonance data. These have been systematically reviewed since 1973 in the Specialist Periodical Reports series [1]. ESR textbooks are listed in References 2-21. The text by Carrington and McLachlan [2] provides a good theoretical background. For a less mathematical treatment intended for a more biological audience, the book by Knowles et al. [13] is useful. 

Table VI lists all the published electron-spin resonance data pertaining to paramagnetic metal phthalocyanines. In addition to the g values, the most commonly recorded datum is the a2 value a = a2 = 1 refers to purely ionic bonding (LXXVII) and values of a2 less than 1 imply some delocalization of the dxi-yi electron onto the phthalocyanine ligand. Thus the value of a2 = 0.54 for silver phthalocyanine may be interpreted to mean that the dtf-yi electron spends 46% of its time on the phthalocyanine ligand. The comparatively low values of a2 reported for copper and silver phthalocyanine 131, 139, 145, 237, 260, 298, 347) suggest a high degree of covalency in these complexes.

It is pertinent to remark when considering electron-spin resonance data that, although the various studies of copper phthalocyanine (16, 181, 189, 140, 210, 239, 260, 261, 299) have yielded essentially the same parameters, the detailed interpretation of these parameters has often been strikingly different. 

Poole, C.P. Farach, H.A. Handbook of electron spin resonance data sources, computer technology, relaxation, and ENDOR. AIP Press, New York, 1994. 

Haemoglobin fluoride is an 5 = 1 iron(III) compound known from electron-spin resonance data to have the 5 = 1> Kramers doublet lying lowest. Spectra between 195 K and 1-2 K show appreciable spin-spin and spin-lattice relaxation effects. The examples in Fig. 13.7 can be compared with the predicted line spectrum. Surprisingly, the spectrum sharpens in... 

According to electron spin resonance data, free radicals are produced at chain ends even before a macroscopic break occurs. The free radical concentration depends only on the extension, and not on the tensile stress. Concentrations of lO -lO free radicals/cm are generally observed. Since free radical concentrations of only about 10 free radicals/cm occur on the surface, free radicals must form in the test sample interior, that is, from the breaking of polymer chains. In addition, chemical decomposition products are produced by a ductile break, but not by a brittle fracture. 

A suitable homogeneous catalyst can be prepared by reacting five moles of diethylaluminum chloride with one mole of vanadium tetrachloride-anisole complex (V/CtHsO =r 1) at —78°C in toluene. Since the catalyst is thermally unstable at room temperature, the best results are obtained at very low temperatures. Electron spin resonance data suggested that the active species involves RVCI2 complexed with organoaluminum compounds (Natta et al., 1965). 

Magnetic susceptibility and electron spin resonance data of self-doped sulfonated polyaniline shows the presence of Curie like susceptibility and temperature independent Pauli like susceptibility. The product of the spin susceptibility and temperature (xT) versus temperature for the emeraldine base sulfonated polyaniline is shown in Figure 2.30 [41]. Based on the Pauli spin concentration, the density of states at the Fermi level N( f) (from the slope) is 0.8 state/eV-two rings and an effective Curie spin concentration (from the T = 0 intercept) is 0.02 spin/two... 

Magnetic hyperfine field parameters for the lanthanide ions based on the results of Freeman and Watson (1962). The experimental free ion values of the total hyperfine field are derived from electron spin resonance data on dilute lanthanide impurities in insulators [Bleaney (1972)]. A positive sign for Htu means that the held has the same direction as the electronic moment. 

---