## Wikipedia - Teoria di Marcus Marcus equation (for electron transfer)

https://doi.org/10.1351/goldbook.M03702
Relation between the rate of @O04351@ and the thermodynamics of this process. Essentially, the @O04322@ within the @E02087@ (or the @O04322@ of @I03130@ transfer) is given by the Eyring equation: $k_{\mathrm{ET}}=\frac{\kappa _{\mathrm{ET}}\ k\ T}{h}\ \exp (- \frac{\Delta G^{\ddagger }}{R\ T})$ where $$k$$ is the @B00695@, $$h$$ the @P04685@, $$R$$ the @G02579@ and $$\kappa _{\text{ET}}$$ the so-called electronic @T06482@ ($$\kappa _{\text{ET}}\sim 1$$ for @A00141@ and $$<<1$$ for @D01659@). For @O04351@ the barrier height can be expressed as: $\Delta G^{\ddagger} = \frac{(\lambda\,+\,\Delta _{\text{ET}}G^{\,\unicode{x26ac}})^{2}}{4\ \lambda }$ where $$\Delta _{\text{ET}}G^{\,\unicode{x26ac}}$$ is the standard Gibbs energy change accompanying the electron-transfer reaction and $$\lambda$$ the total reorganization energy.
Note:
Whereas the classical Marcus equation has been found to be quite adequate in the normal region, it is now generally accepted that in the inverted region a more elaborate formulation, taking into account explicitly the Franck–Condon factor due to quantum mechanical vibration modes, should be employed.
Source:
PAC, 2007, 79, 293. (Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)) on page 368 [Terms] [Paper]