Organosilicon radical cations

The 71 subunits, ethene and benzene, differing in both size as well as topology, but containing the same tetra-substitution pattern, seem to approach identity15,16. ESR spin delocalization data of their organosilicon radical cations as well as additional information from own structures of sterically overcrowded molecules and many more registered in the Cambridge Structural Database stimulate speculation that both tetra-substituted molecules... 

In this section, the selected topics of photoelectron spectroscopic investigations on silicocene (Section IV.B.l), the charge delocalization in (I Si Si—Si(SiR3)3 (Section IVB.2) and matrix isolation of organosilicon radical cations (Section IVB.3) are presented. Table 3 will provide data on all other organosilicon molecules investigated by their ionization patterns. 

H. Bock and B. Solouki, Chem. Rev., 95, 1161 -1190 (1995), summarize generation and properties of Organosilicon Radical Cations including the PE spectroscopic prediction of their possible generation in solution. 

III. GENERATION OF ORGANOSILICON RADICAL CATIONS IN SOLUTION AS PREDICTED BY FIRST PES IONIZATION ENERGIES AND... 

To study organosilicon radical cations in solution, a general procedure has been developed, indeed a recipe, for their generation based on photoelectron spectroscopy16 ... 

Summarizing, much can be learned about organosilicon radical cations from the ESR/ENDOR data base collected. Their ground state differs completely from that of radical anions of the very same compound (schemes 24 and 25) and their spin population—as well as the charge distribution—can be considerably changed by substituents (scheme 23). 

The fluxtionality of organosilicon radical cations as observed by the ESR/ENDOR probe within its time window shows another essential facet of their ground-state properties the storage of internal energy in the 3n-6 degrees of freedom of nonlinear n-atomic molecular ions. 

H. Bock and W. Kaim, Acc. Chem. Res., 15, 9 (1982) review ESR/ENDOR information on organosilicon radical cations in solution, generated by single electron transfer as predicted by PE spectroscopic first ionization potentials. 

ESR/ENDOR spectroscopy, and especially the Si-ENDOR method developed [25], yield a wealth of information about the ground states of numerous organosilicon radical cations generated... 

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