Wikipedia - Dexter electron transfer (en) Wikipedia - Dexter-Energietransfer (de) Wikipedia - Quenching (fluorescence) (en) Wikipedia - דיכוי פלואורסצנטי (he) Dexter excitation transfer (electron exchange excitation transfer)

https://doi.org/10.1351/goldbook.D01654
@E02256@ occurring as a result of an electron exchange mechanism. It requires an overlap of the wavefunctions of the energy donor and the energy acceptor. It is the dominant mechanism in @T06506@. The transfer @O04322@, $$k_{\mathrm{ET}}$$, is given by: $k_{\text{ET}}\propto \frac{h}{2\ \pi }\ P^{2}\ J\ \text{e}^{\frac{-2\ r}{L}}$ where $$r$$ is the distance between donor (D) and acceptor (A), $$L$$ and $$P$$ are constants not easily related to experimentally determinable quantities, and $$J$$ is the @S05818@ integral. For this mechanism the spin conservation rules are obeyed.