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en:reactivity:radical_addition:altpmo [2026/09/18 13:32] – abcen:reactivity:radical_addition:altpmo [2026/09/23 09:53] (current) – abc
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 and and
 {{:reactivity:radical_addition:altpmo-3.png?direct&160|}} {{:reactivity:radical_addition:altpmo-3.png?direct&160|}}
-<html><span class="rfloat"><b>(eq. 1')</b></span></html>+<html><span class="rfloat"><br><b>(eq. 1')</b></span></html>
  
 Values //E<sub>M→R</sub>// and //E<sub>M←R</sub>// can be regarded as the efficient energies of occupied and unoccupied orbital shells of the first reagent //M// related to the orbitals of the second reagent //R//. A more convenient notation looks like this: \\ Values //E<sub>M→R</sub>// and //E<sub>M←R</sub>// can be regarded as the efficient energies of occupied and unoccupied orbital shells of the first reagent //M// related to the orbitals of the second reagent //R//. A more convenient notation looks like this: \\
 {{:reactivity:radical_addition:altpmo-4.png?direct&125| }} , {{:reactivity:radical_addition:altpmo-4.png?direct&125| }} ,
 where //N = E<sub>M→R</sub> + E<sub>M←R</sub>// and //G = E<sub>M←R</sub> − E<sub>M→R</sub>//. where //N = E<sub>M→R</sub> + E<sub>M←R</sub>// and //G = E<sub>M←R</sub> − E<sub>M→R</sub>//.
-<html><span class="rfloat"><b>(eq. 2)</b></span></html>+<html><span class="rfloat"><br><b>(eq. 2)</b></span></html>
  
  
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 Despite all this there is a great limitation of **Eq. (2)**: parameters //N/G// are individual (relative) values for **each reaction series**, and so should be used in such a series with one fixed reagent. But fortunately these parameters of different series appeared to be linearly dependent! In general it cannot be true, but in some approximation it could happen for some narrow classes of reagents. Only a computational experiment can prove or deny it. And, it was revealed that ours was such a case. In all considered reactions, relative scales of monomers' //N// and //G// correlate linearly surprisingly well (see, e.g., Fig. 5). This makes it possible to build a sort of universal scale of //N// for the radical addition to vinyl //C=C// bond. So, **Eq. (2)** for CT energy obtain the following form, where gaps are summed and electronegatives are substracted: Despite all this there is a great limitation of **Eq. (2)**: parameters //N/G// are individual (relative) values for **each reaction series**, and so should be used in such a series with one fixed reagent. But fortunately these parameters of different series appeared to be linearly dependent! In general it cannot be true, but in some approximation it could happen for some narrow classes of reagents. Only a computational experiment can prove or deny it. And, it was revealed that ours was such a case. In all considered reactions, relative scales of monomers' //N// and //G// correlate linearly surprisingly well (see, e.g., Fig. 5). This makes it possible to build a sort of universal scale of //N// for the radical addition to vinyl //C=C// bond. So, **Eq. (2)** for CT energy obtain the following form, where gaps are summed and electronegatives are substracted:
  
-{{  :reactivity:radical_addition:altpmo-5.png?direct&200  |}} +{{:reactivity:radical_addition:altpmo-5.png?direct&200|}} 
-<html><span class="rfloat"><b>(eq. 2')</b></span></html>+<html><span class="rfloat"><br><b>(eq. 2')</b></span></html>
  
 **The proposed procedure of calculation of //N/G// parameters has general character and by no means is restricted by the frames of radical addition reaction or even π-approximation. Moreover, one can try to split total term on σ- and π-terms and so get two pairs of //N/G// parameters, one characterizing the σ shell and the other the π one.** **The proposed procedure of calculation of //N/G// parameters has general character and by no means is restricted by the frames of radical addition reaction or even π-approximation. Moreover, one can try to split total term on σ- and π-terms and so get two pairs of //N/G// parameters, one characterizing the σ shell and the other the π one.**
 +
 +----
  
 === Figure 5 === === Figure 5 ===
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 {{:reactivity:radical_addition:altpmo-6.png?direct&300|}} {{:reactivity:radical_addition:altpmo-6.png?direct&300|}}
- 
  
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