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--- en:reactivity:radical_addition:intro [2026/09/10 11:08] – abc
+++ en:reactivity:radical_addition:intro [2026/09/10 11:10] (current) – abc
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 Since the pioneer works of Fukui [ [[ref|6]] ], the main approach to discussion of radical reactivity became the method of boundary molecular orbitals (MOs), and its extreme variant of using ionization potential (or electron affinity, depending on the relation of donor–acceptor properties of reagents) as an index of reactivity of monomers/radicals. For example, this approach was good enough for studies of reactivity of alkyl radicals toward vinyl monomers [ [[ref|7]] ].
-Now, this study is another ambitious attempt to build some universal model of reactivity of vinyl monomers //CH<sub>2</sub>=CXY// in radical addition reactions, using for the basis a theoretical investigation of reactivity of the C=C bond. For the basic concept of this approach we assumed that criterion of reactivity of reagents should be not experimental data but directly calculated activation barriers (experimental activation energies are not numerous and reliable enough). This enabled us to reveal true electronic factors of reactivity and avoid effects caused by differences of experimental conditions, for example, influence of solvents. For this purpose there were performed a series of calculations of reactions of C- and O-centered radicals //CH<sub>3</sub><sup>•</sup>//, //CH<sub>3</sub>O<sup>•</sup>//, //CCl<sub>3</sub><sup>•</sup>//, //CF<sub>3</sub><sup>•</sup>//, and //HOO<sup>•</sup>// and vinyl monomers //CH<sub>2</sub>CHX//, both ordinary ones as vinyl acrylate and with conjugated double bonds (butadiene, styrene, etc.) [ [[ref|8]] ].
+Now, this study is another ambitious attempt to build some universal model of reactivity of vinyl monomers //CH<sub>2</sub>=CXY// in radical addition reactions, using for the basis a theoretical investigation of reactivity of the C=C bond. **For the basic concept of this approach we assumed that criterion of reactivity of reagents should be not experimental data but directly calculated activation barriers** (experimental activation energies are not numerous and reliable enough). This enabled us to reveal true electronic factors of reactivity and avoid effects caused by differences of experimental conditions, for example, influence of solvents. For this purpose there were performed a series of calculations of reactions of C- and O-centered radicals //CH<sub>3</sub><sup>•</sup>//, //CH<sub>3</sub>O<sup>•</sup>//, //CCl<sub>3</sub><sup>•</sup>//, //CF<sub>3</sub><sup>•</sup>//, and //HOO<sup>•</sup>// and vinyl monomers //CH<sub>2</sub>CHX//, both ordinary ones as vinyl acrylate and with conjugated double bonds (butadiene, styrene, etc.) [ [[ref|8]] ].
 A special part of this article is the new model of electronegativities that was derived from the perturbated MO (PMO) theory equation as its alternative. It has general character and can be applied in any studies of reactivity where the PMO approach could be used.