Isomerism organic radical ions

In materials containing open-shell polyoxoanions, ferroceniiun ions or the organic radical mpyNIT great attention was devoted to the influence of the additional paramagnetic species on the relaxation of the Mni2 unit. However, the interpretation of the results is still controversial, due to the possible implication of JT isomerism and other environmental factors [44]. 

In a number of cases quantum-chemical calculations have confirmed the experimentally determined distribution of unpaired electron density in a radical ion [94]. In addition the hyperfine structure of the spectrum can serve as an experimental basis for verification and confirmation of the validity of complex quantum-chemical calculations applied to the structure of organic molecules and radicals. The hyperfine structure can also serve to identify a given type of radical, and to offer information on the coplanarity and isomerism of radical anions it can also be used to determine the rates of transi-... 

Accumulation and organization of information can be achieved on the base of cis-trans isomerization of olefins in their ion radical states. In preceding chapters, the phenomenon was... 

Many organic reactions occurring over crystalline aluminosilicates can be rationalized as proceeding via carbonium ions, or related organic cations. Scrutiny of the literature and examination of some recent work suggests that there may be exceptions. For instance, a free radical mechanism for isomerization of 1-butene over Cu-exchanged NaX has been proposed at lov copper contents (15). 

Fig. 5.25 Biological NO, chemistry adapted and simplified from Fukuto et al. (2000). Dotted arrow multistep process, Me transition metal ion, RSFl organic sulfide (-SF1 thiol group), RSSH disulfide, ONOO is an isomeric form of the nitrate radical NO3, ONOO (ONOOH) peroxonitrous acid, HON=NOH (H2N2O2) hyponitrous acid, N2O2 (0=N—N—0 ) radical anion of NO dimer, N3O3 (0=N—N—O—NO ) trimer radical anion (not to confuse with Angeli salt N304 [O2N—N—N02] ).

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