Carbocations and stability

The actual role of the added nucleophile is still under discussion [41,88,92] (cf., Sections VI.B.2 and VILE.4). They may interact with the growing carbocations and stabilize them through the weak solvating interactions [36]. Another possibility is that the added nucleophiles and the growing carbocations form reversibly onium ions that serve as dormant species, as discussed by Penczek [92] and Matyjaszewski [88] (schemati-... 

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